Questions/Answers and Explanations
Each of the following questions or incomplete statements is followed by suggested answers or completions. Select the ONE BEST ANSWER in each case.
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1. A 42-year-old female presents with the lesion (shown at left) on the back of her calf. She has no significant medical problems and otherwise feels well. The lesion has not bled, but seems to have grown over the last few months. Appropriate initial management of this skin lesion should be
A) observation and removal if bleeding or further change occurs
B) complete excision with normal margins
C) complete excision with wide margins
D) shave biopsy
E) electrodessication and curettage
View Answer
1. The answer is B. (Complete excision with normal margins) Even in the hands of experienced dermatologists, there is an approximately 15% false negative rate in determining the presence of melanoma based on examination alone; therefore, histologic confirmation is essential for both tumor diagnosis and staging. A complete excision with normal skin margins is preferable when possible as the first diagnostic step (e.g., excisional biopsy). An incisional biopsy can be performed for larger lesions when complete excision is not practical and when the suspicion of melanoma is low; incisional biopsy does not adversely affect survival. Shave biopsies should be avoided because they may not provide enough tissue for diagnosis and do not allow for accurate depth measurement. All biopsies of lesions suspected of being melanomas should provide a piece of full-thickness skin extending to the subcutaneous fat.
Sober AJ, Chuang TY, Duvic M, et al. Guidelines of care for primary cutaneous melanoma. J Am Acad Dermatol. 2001;45:579.
Bong JL, Herd RM, Hunter JA. Incisional biopsy and melanoma prognosis. J Am Acad Dermatol. 2002;46:690.
When considering the diagnosis of melanoma, shave biopsies should be avoided because they may not provide enough tissue for diagnosis and do not allow for accurate depth measurement. All biopsies of lesions suspected of being melanomas should provide a piece of full-thickness skin extending to the subcutaneous fat.
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2. A 26-year-old female presents with the above rash. She states the rash is minimally pruritic and developed over the last week. She has had some virus-like symptoms and reports the rash began as a large salmon-colored patch on her chest area. The most likely diagnosis is
A) tinea versicolor
B) pityriasis rosea
C) varicella
D) psoriasis
E) cocciodiomycosis
View Answer
2. The answer is B. (Pityriasis rosea) Pityriasis rosea is a self-limited, exanthematous skin disease that develops acutely and is characterized by the appearance of slightly inflammatory, oval, papulosquamous lesions on the trunk and proximal areas of the extremities. Pityriasis rosea is largely a disease of older children and young adults. It is more common in women than men. A prodrome of headache, malaise, and pharyngitis may occur in a small number of cases, but except for itching, the condition is usually asymptomatic. The eruption commonly begins with a “herald patch”: a single round or oval, sharply demarcated pink or salmon-colored lesion on the chest, neck, or back, 2 to 5 cm in diameter. The lesion soon becomes scaly and begins to clear centrally, leaving the free edge of the scaly lesion directed inwards toward the center. A few days or a week or two later, oval lesions similar in appearance to the herald patch, but smaller, appear in crops on the trunk and proximal areas of the extremities The long axes of these oval lesions tend to be oriented along the lines of cleavage of the skin. This characteristic Christmas-tree pattern is most evident on the back, where it is emphasized by the oblique direction of the cleavage lines in that location. Most cases of pityriasis rosea need no treatment other than reassurance and proper patient education. Topical steroids with moderate potency are helpful in the control of itching. They can be applied to the pruritic areas two or three times daily. Topical antipruritic lotions such as prax, pramagel, or sarna may also be helpful.
Chuh AA. Quality of life in children with pityriasis rosea: a prospective case control study. Pediatr Dermatol. 2003;20:474.
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3. An 18 year old presents to your office complaining of a sandpaper-like rash that affects his upper outer arms. He is otherwise healthy and has no other symptoms. The most likely diagnosis is
A) scarlet fever
B) infectious mononucleosis
C) keratosis pilaris
D) seborrheic dermatitis
E) psoriasis
View Answer
3. The answer is C. (Keratosis pilaris) Keratosis pilaris is defined as hyperkeratotic follicular papules on the extensor surface of the upper arms or upper anterior thighs and occasionally on the malar area of the face. It may be associated with atopy and dry skin. A sandpaper-like feel is noted in these isolated areas. The condition is considered benign and is treated with topical lactic acid cream or lotion. Lesions that are associated with the face typically resolve at puberty.
Frankel DH. Field Guide to Clinical Dermatology. Philadelphia: Lippincott Williams & Wilkins; 1999:9.
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4. A 35-year-old woman presents with a pruritic rash that has been present over the last few weeks. The area affected is in the webs of the fingers, and symptoms are reported to be worse at night. Topical over-the-counter steroids have not been beneficial. The likely diagnosis is
A) poison ivy
B) dyshidrotic eczema
C) scabies
D) tinea corporis
E) psoriasis
View Answer
4. The answer is C. (Scabies) The condition of scabies is associated with intense pruritus that is noted predominantly at night. The lesions are brownish in color and often form irregular burrow lines that may be marked with scaling at one end and a vesicle at the other end. The lesions are typically found in intertriginous areas and warm, protected areas such as the finger webs, inframammary areas, and axilla. The mite Sarcoptes scabei is responsible. Scrapings of the lesion are treated with 10% potassium hydroxide solution and studied under light microscopy. The mite is often identified. Treatment consists of permethrin cream 5% applied from head to toes and left in place for 12 hours before being washed off. Lindane can also be used as an alternative, but not in infants or in pregnant women.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:228.
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5. A 72-year-old man presents to your office complaining of an area of redness associated with the perinasal region. He states that the rash is often worse in the summer, and he has noticed that sunlight exposure makes it worse. Appropriate treatment of this condition consists of
A) hydrocortisone cream
B) tretinoin gel
C) metronidazole cream
D) mupirocin ointment
E) acyclovir ointment
View Answer
5. The answer is C. (Rosacea) Rosacea is a common problem encountered by family physicians. The condition is associated with areas of erythema and telangiectasia on the face. It is exacerbated by sunlight, hot or spicy foods, and alcohol. Pronounced rosacea may appear as acneiform papules, pustules, or ruddiness. Northern Europeans and those of Celtic descent are most commonly affected. Treatment involves oral tetracycline or doxycycline. Topical metronidazole is also effective for milder cases.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:123.
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6. Which of the following malignancies is associated with the skin condition shown here?
A) Ovarian carcinoma
B) Gastric carcinoma
C) Malignant melanoma
D) Multiple myeloma
E) Hodgkin's lymphoma
View Answer
6. The answer is B. (Acanthosis nigricans) Acanthosis nigricans is associated with hyperpigmented areas that typically affect flexural folds (axilla). The two basic types of acanthosis nigricans are benign and malignant. The benign form is associated with obesity, diabetes, Stein-Leventhal syndrome, Cushing's disease, Addison's disease, pituitary disorders, and hyperandrogenic syndromes. Drugs, including glucocorticoids, nicotinic acid, diethylstilbestrol, and growth hormone therapy, have also caused acanthosis nigricans. Many cases are idiopathic. Malignant acanthosis nigricans is associated with an intestinal cancer such as gastric carcinoma.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:260.
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7. A 45-year-old woman presents with a localized area of erythematous scaly patches that comes and goes and typically affects the elbows. The likely diagnosis is
A) pityriasis rosacea
B) mycosis fungoides
C) tinea corpora
D) nummular eczema
E) psoriasis
View Answer
7. The answer is E. (Psoriasis) Psoriasis usually manifests itself as erythematous scaly patches that affect the knees or elbows. More severe cases can involve multiple areas over the entire body. Extensor surfaces are predominantly affected. Nail pitting may be present. The condition appears to be hereditary. Diagnosis is usually based on clinical findings. Skin biopsy may be helpful for definitive diagnosis. Treatment consists of topical steroids, intralesional steroids, tar preparations, anthralin, tazarotene, and calcipotriene.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:131.
Psoriasis usually manifests itself as erythematous scaly patches that affect the knees or elbows. More severe cases can involve multiple areas over the entire body. Extensor surfaces are predominantly affected. Nail pitting may be present.
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8. A 60-year-old retired construction worker presents with a non-healing skin lesion on the back of his hand that occasionally bleeds when he gets out of the shower. The most likely diagnosis is
A) basal cell carcinoma
B) squamous cell carcinoma
C) superficial spreading malignant melanoma
D) actinic keratosis
E) keratoacanthoma
View Answer
8. The answer is A. (Basal cell carcinoma) Basal cell carcinoma is the most common form of skin cancer. The lesions are induced by ultraviolet radiation in susceptible individuals. Risk factors include age older than 40, light complexion, positive family history, and male sex. The lesion has pearly, raised borders with telangiectasia and a central ulcer that may crust. Sun-exposed areas are most commonly affected. Diagnosis is achieved with shave or excisional biopsy. Treatment is accomplished with excision, electrodessication and curettage, liquid nitrogen application, Moh's surgery, radiation treatment, and topical 5-fluorouracil cream. Almost 50% of patients with basal cell carcinoma will have another within 5 years.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:386.
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9. You note the above skin disorder during a general medical evaluation. You explain to the patient they are at risk for the development of:
A) Alzheimer's disease
B) tuberculosis
C) diabetes mellitus
D) Grave's disease
E) melanoma
View Answer
9. The answer is C. (Diabetes mellitus) Although the majority of cases of acanthosis nigricans are benign and associated with obesity, the disease can represent the onset of malignancy as well as a variety of conditions related to insulin resistance. Acanthosis nigricans has been reported in association with a number of malignancies, particular gastrointestinal cancers (e.g., gastric, hepatocellular) and lung cancer. The suspicion for malignancy increases in patients with extensive or rapidly progressive lesions, when there is mucous membrane involvement, or when there is prominent sole and palm disease. The common finding in all non-malignancy associated cases of acanthosis nigricans is insulin resistance. This explains the relationship between this skin disorder and diseases such as diabetes mellitus, Cushing's syndrome, and hypothyroidism (most likely due to weight gain and subsequent insulin resistance), and with obesity.
Shwayder T. Disorders of keratinization: diagnosis and management. Am J Clin Dermatol. 2004;5:17.
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10. A 42-year-old female presents to the Emergency Room complaining of shortness of breath and palpitations. An electrocardiogram shows the above tracing. Appropriate management at this time includes:
A) Epinephrine
B) Metoprolol
C) Nitroglycerin
D) Adenosine
E) Lidocaine
View Answer
10. The answer is D. (Adenosine) The most important step to make when a narrow QRS tachycardia is noted is whether the patient is experiencing signs and symptoms related to the rapid heart rate. These symptoms include hypotension, shortness of breath, shock, decreased level of consciousness, or chest pain suggestive of coronary ischemia. Determining whether a patient's symptoms are related to the tachycardia depends on several factors, including age and the presence of underlying cardiac disease. Paroxysmal supraventricular tachycardia (PSVT) with a heart rate of 200 bpm may be tolerated by a healthy young adult with no or few symptoms (e.g., palpitations). However, a heart rate of 120 bpm may precipitate angina in an elderly patient with significant coronary heart disease. Adenosine is approved by the Food and Drug Administration (FDA) in the United States only for the intravenous management of PSVT in which the AV node is involved. For intravenous adenosine administration, the patient should be supine and should have electrocardiographic and blood pressure monitoring. The drug is administered by rapid intravenous injection over one to two seconds at a peripheral site, followed by a normal saline flush. The usual initial dose is 6 mg, with a maximal single dose of 12 mg. The most common side effects of adenosine are facial flushing (18%), palpitations, chest pain, and hypotension. Transient asystole is a rare complication. Another important side effect of adenosine is that it may precipitate atrial fibrillation (AF). In patients with Wolf-Parkinson-White syndrome (WPW), AF can progress into ventricular fibrillation. As a result, caution should be used when giving adenosine if WPW is a possible mechanism, and emergency resuscitation equipment should be available.
Arnsdorf MF, Ganz LI. Approach to narrow QRS complex tachycardias. Up to Date, version 14.1. Accessed 5/1/06.
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11. A 4-year-old preschooler presents with the skin lesions shown here. The area affected is just below the chin on the child's right side. The lesions have been present over the last month, and the child has reported no symptoms associated with them. The most likely diagnosis is
A) varicella
B) herpes zoster
C) Rhus dermatitis
D) molluscum contagiosum
E) scabies
View Answer
11. The answer is D. (Molluscum contagiosum) Molluscum contagiosum is a common, superficial viral infection of the skin that typically occurs in infants and preschoolers. The incidence decreases after the age of 6 to 7 years. The condition can be spread via sexual contact in young adults. The lesions are dome-shaped, waxy, or pearly-white papules with a central white core and are 1 to 3 mm in diameter. Frequently, groups of lesions are found. The lesions may resolve spontaneously. Treatment involves removal with a sharp needle or curette, application of liquid nitrogen, antiwart preparations, electrodessication and curettage, or trichloroacetic peels for extensive areas. Typically, infants or young preschool-age children should not be treated aggressively.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:188.
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12. A 16-year-old girl who just returned from a camping trip reports an intensely pruritic vesicular rash associated with the lower extremities. The most likely diagnosis is
A) Rhus dermatitis
B) Lyme disease
C) chigger bite
D) brown recluse spider bite
E) black widow spider bite
View Answer
12. The answer is A. (Rhus dermatitis) Poison ivy or poison oak is also referred to as Rhus dermatitis. The condition is associated with intensely pruritic linear streaks of vesicles, papules, and blisters. The plants contain a resinous oil that gives rise to an allergic response approximately 2 days after exposure. Contrary to common belief, the fluid in the blisters can neither transfer the rash to others nor cause it to spread. Treatment involves topical steroid creams, Burow's solution, calamine lotion, antihistamines, cool baths with colloidal oatmeal, and oral steroids (for 2 to 3 weeks to prevent rebound dermatitis) for more widespread cases.
Goodheart HP. A Photoguide of Common Skin Disorders: Diagnosis and Management. Philadelphia: Lippincott Williams & Wilkins; 1999:42–43.
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13. An 82-year-old nursing home resident is seen on monthly rounds. The floor nurse points out the skin lesions shown here. The patient is asymptomatic. Appropriate management includes
A) punch biopsy
B) topical 5-fluorouracil cream
C) cryotherapy
D) hydrocortisone cream
E) observation
View Answer
13. The answer is E. (Seborrheic keratoses) Seborrheic keratoses are common skin lesions that affect the elderly. They tend to run in families. The average diameter is 1 cm, but they can grow to 3 cm in diameter. The lesions are brown or black, oval in shape, raised, and have a “stuck on” appearance. They most commonly occur on the face, back, neck, and scalp. They may appear suddenly and become pruritic and crusted. Numerous lesions that appear rapidly may signal the development of an underlying malignancy. Treatment is cosmetic and usually reserved for those that are inflamed or causing symptoms.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:324–325.
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14. An 18-year-old sexually active female presents with a single ulcer that is located on the lower lip and is painful. She is a smoker and has noticed that the ulcers have been recurrent and correlate with the onset of menses. The most likely diagnosis is
A) Kawasaki disease
B) apthous stomatitis
C) squamous cell carcinoma of the lip
D) syphilis
E) Koplik's spot
View Answer
14. The answer is B. (Apthous stomatitis) Apthous stomatitis, also known as canker sores, are painful eruptions that affect the mucosal surface of the mouth. The cause is unknown. Lesions typically develop at the same time and resolve in 5 to 10 days. A viral cause has not been proved. A streptococcal bacteria has been implicated. The lesions recur at regular intervals and may correlate with the onset of menses in some women. Treatment consists of toothpaste swish therapy, triamcinolone acetonide (Kenalog in Orabase), or tetracycline solution swish and swallow. Severe cases may respond to systemic corticosteroids.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:289–290.
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15. Which of the following conditions is the skin finding shown here associated with?
A) Prolonged antibiotic use
B) Sjögren's syndrome
C) Addison's disease
D) Chronic gastroesophageal reflux
E) Malignant melanoma
View Answer
15. The answer is A. (Black tongue) Black hairy tongue results from hyperplasia of the filiform papillae with deposition of keratin on the surface. The condition causes the tongue to have a dark, velvety, hairlike appearance. Associated conditions include smoking, consumption of coffee, prolonged use of antibiotics, and possibly acquired immunodeficiency syndrome. Treatment involves using a toothbrush to scrape off the excess keratin that forms on the tongue's surface.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:291.
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16. A 38-year-old man presents with rapid hair loss that has occurred over the last few weeks. He reports that his father had a similar condition. The most likely diagnosis is
A) alopecia areata
B) androgenic alopecia
C) tinea capitis
D) trichotillomania
E) secondary syphilis
View Answer
16. The answer is A. (Alopecia areata) Alopecia areata is associated with sudden hair loss that occurs in round patches. The patches are well circumscribed and are not associated with scarring or inflammation. Patients have no other symptoms. The most common area affected is the scalp; however, the condition may also affect the eyebrows or beard. Alopecia areata usually affects children and young adults and is recurrent. A pathognomonic sign for alopecia areata is the “exclamation point” hair, which is wide distally and narrower at the base. These hairs are often found at the periphery of a patch of hair loss. Hair that regrows in the area of alopecia areata is in many cases white. Nail pitting may also be present. The treatment consists of injection of intralesional steroids and topical steroids. Most experience complete regrowth of hair.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:273.
Alopecia areata is associated with sudden hair loss that occurs in round patches. The patches are well circumscribed and are not associated with scarring or inflammation.
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17. The condition shown here was noted associated with an 88-year-old debilitated nursing home resident. He has no evidence of bacteremia or osteomyelitis. Which of the following is an acceptable treatment?
A) application of povidone-iodine gauze two times per day
B) application of hydrogen peroxide 3 times per day
C) systemic antibiotics for 7 to 10 days
D) keeping the area clean and dry until granulation tissue forms
E) surgical debridement
View Answer
17. The answer is E. (Surgical débridement) When treating pressure ulcers, it is important to maintain a moist environment while keeping the surrounding skin dry. This can be accomplished by loosely packing the ulcer with saline-moistened gauze. Topical antimicrobials such as silver sulfadiazine cream may be helpful in ulcers that appear infected. Topical antiseptics such as povidone-iodine or hydrogen peroxide should be not be used in the treatment of pressure ulcers. Systemic antibiotics should be reserved for serious infections (e.g., bacteremia, osteomyelitis). A 2-week trial of topical antimicrobials may be considered for ulcers that do not appear infected but are not improving. Although most patients are successfully managed without surgery, procedures may be appropriate in patients whose quality of life would be markedly improved by rapid wound closure. Stage 3 and 4 ulcers with necrotic tissue should be débrided. Ulcers with minimal exudate that are not infected can be covered with an occlusive dressing to promote autolytic débridement. Ulcers with thick exudate, slough, or loose necrotic tissue should undergo mechanical débridement. Options include wet-to-dry dressings, hydrotherapy, wound irrigation, and scrubbing the wound with gauze. Ulcers with evidence of cellulitis or deep infection should undergo sharp débridement with a scalpel or scissors. Ulcers with a thick eschar or extensive necrotic tissue should undergo sharp débridement as well. However, a thick, dry eschar covering a heel ulcer should generally be left intact. Patients without access to surgical inter-ventions (such as in a long-term care setting) or those who may not be acceptable surgery candidates can be treated with enzymatic débriding agents. Wound débridement should stop once necrotic tissue has been removed and granulation tissue is present.
Berlowitz D. Prevention and treatment of pressure ulcers. Up to Date, version 14.1. Accessed 5/3/06.
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18. A 35 year old presents with unilateral hearing loss that has been gradual but progressive over the last 6 months. Appropriate treatment of the above condition consists of
A) prolonged antibiotics for up to 4 weeks
B) decongestant and antihistamine administration
C) corticosteroid treatment for 2 weeks
D) hearing aid amplification
E) tympanomastoidectomy
View Answer
18. The answer is E. (Tympanomastoidectomy) Cholesteatoma is a growth of desquamated, stratified, squamous epithelium within the middle ear space. The condition occurs when keratin desquamates from the epithelial lining of the sac and gradually enlarges with eventual erosion of the ossicular chain, mastoid bowl, and external auditory canal. The development of a cholesteatoma typically occurs after a retraction pocket has formed in the posterior/superior quadrant of the ear, often as a result of chronic eustachian tube dysfunction. It may also occur after tympanic membrane (TM) trauma, such as a traumatic, inflammatory, or iatrogenic perforation. Without treatment, cholesteatomas may erode the tegman (the bony covering of the middle fossa), the sigmoid sinus, or even the inner ear. As a result untreated cholesteatomas can result in lateral sinus thrombosis, sepsis, brain abscess, sensorineural hearing loss, vertigo, disequilibrium, facial paralysis, and even death. Treatment is surgical, usually involving a tympanomastoidectomy.
Weber PC. Etiology of hearing loss in adults. Up to Date, version 14.1. Accessed 5/3/06.
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19. A 27-year-old gravida 2, para 2 woman is now 6 months postpartum and complains of excessive hair loss. The most likely diagnosis is
A) alopecia areata
B) telogen effluvium
C) trichotillomania
D) tinea capitis
E) hypothyroidism
View Answer
19. The answer is B. (Telogen effluvium) Telogen effluvium is sudden, diffuse hair loss that occurs 3 to 6 months after a stressful event. The causes include medications (heparin, coumarin, propranolol, haloperidol, and lithium), neoplasms, infection, and crash diets. The stressful event triggers the hair follicles to go into a rest phase, and once the cycle returns a larger amount of hair is lost at one time. Typically, 30% to 50% of the scalp hair is affected. No treatment is needed. Patients should be reassured that normal hair growth should resume.
Frankel DH. Field Guide to Clinical Dermatology. Philadelphia: Lippincott Williams & Wilkins; 1999:187–188.
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20. A 68-year-old man is seen for a general examination and reports a dome-shaped lesion on the back of the hand that has developed over the last few weeks. The lesion is rapidly becoming larger. The most likely diagnosis is
A) basal cell carcinoma
B) squamous cell carcinoma
C) seborrheic keratosis
D) actinic keratosis
E) keratoacanthoma
View Answer
20. The answer is E. (Keratoacanthomas) Keratoacanthomas usually develop rapidly over a 2- to 6-week time frame. The lesions are dome-shaped with a central keratin-filled plug. They occur most commonly on sun-exposed areas. Many resolve spontaneously; however, because of their similarity to squamous cell carcinomas and their ability to metastasize, they should be removed by excision. Other treatment options include intralesional methotrexate, 5-fluorouracil, interferon, systemic retinoids, or radiation therapy. Complete excision is usually curative; however, recurrences can develop at the site of treated lesions.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:338.
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21. A 55-year-old woman complains of generalized fatigue, weakness, inability to climb stairs, arthralgias, and dysphagia. Physical examination reveals definite proximal muscle weakness, a periorbital heliotrope rash, and skin findings associated with the hands (shown here). The most likely diagnosis is
A) lupus erythematosus
B) sarcoidosis
C) Sjögren's disease
D) dermatomyositis
E) polymyalgia rheumatica
View Answer
21. The answer is D. (Dermatomyositis) Dermatomyositis presents with a heliotrope rash and the presence of Gottron's papules. The rash is violaceous in color and involves the periorbital areas. Gottron's papules are erythematous or violaceous papules or plaques that form over the bony prominences, particularly the metacarpophalangeal joints, the proximal and distal interphalangeal joints. The condition is also associated with a myopathy that involves the proximal muscles. The shoulders and pelvic girdle are mainly affected in a symmetric pattern. Symptoms include fatigue, weakness, inability to climb stairs, or weakness in rising from a squatting or sitting position. Dysphagia is also seen. Approximately 20% of patients have an associated malignancy. Laboratory tests include elevated serum creatine kinase or aldolase, or both. Electromyographic studies and a muscle biopsy can also provide additional diagnostic information. The mainstays of treatment are systemic steroids. Other options include immunosuppressant agents and hydroxychloroquine. Those who are older and have severe myositis, dysphagia, associated malignancy, and a poor response to corticosteroids have a poorer prognosis.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:253.
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22. A 50-year-old housewife who enjoys growing roses presents to your office complaining of the lesion shown here. She reports removing a thorn from the area several weeks before. After that, a small painless lump developed that now has crusted over. The most likely diagnosis is
A) sporotrichosis
B) blastomycosis
C) Lyme disease
D) coccidioidomycosis
E) histoplasmosis
View Answer
22. The answer is A. (Sporotrichosis) Sporotrichosis is a granulomatous fungal infection that affects the skin. The lesion is caused by Sporothrix schenckii, a fungus that grows on wood and in the soil. The lesions typically affect farmers, gardeners (especially those who grow roses), laborers, and miners. A primary chancre occurs at the site of inoculation. The primary lesion is painless and forms a subcutaneous nodule that breaks down to form an ulcer. Within a few weeks multiple nodules form along the areas of draining lymphatics and break down to form streaks of ulcers, often affecting the arms or legs. The fluid from unopened ulcers can be cultured and can aid in diagnosis. Treatment consists of saturated solution of potassium iodide, ketoconazole, or itraconazole. Systemic invasion is rare.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:405.
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23. A 23-year-old Navy enlisted man is seen in sick bay with the recurrent lesion shown here. The patient reports pain and discomfort associated with the lesion but no dysuria. The likely diagnosis is
A) molluscum contagiosum
B) gonorrhea
C) syphilis
D) chancroid
E) herpes infection
View Answer
23. The answer is E. (Herpes infection) Genital herpes is primarily associated with herpes simplex virus type 2. The symptoms include painful vesicles that occur in clusters, often on the shaft of the penis or vulvar areas of females. Patients often report fever, regional lymphadenopathy, and generalized fatigue in association with an outbreak. The lesions last for 2 to 3 days before the tops of the vesicles rupture. The remaining ulcers crust over and last an additional 5 to 7 days. Recurrences are common in the same area. Asymptomatic shedding of the virus can occur once the outbreak has resolved and can infect others. Diagnosis can be achieved with the use of Tzanck smears (which detect large bizarre mononucleate and multinucleate giant cells and nuclear changes of ballooning degeneration). Treatment is accomplished with the use of antiviral medications (acyclovir, valacyclovir, famciclovir, and topical penciclovir). Prophylactic therapy may be indicated in recurrent infections.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:176–179.
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24. A 23-year-old black woman presents with a lesion affecting her groin that has developed over the last few days. Dark-field microscopic examination is negative. The etiologic agent that is responsible for the lesion is
A) Neisseria gonorrhoeae
B) herpes zoster
C) Treponema pallidum
D) molluscum contagiosum
E) Haemophilus ducreyi
View Answer
24. The answer is E. (Haemophilus ducreyi) Chancroid is a sexually transmitted disease that is caused by Haemophilus ducreyi. It has a very short (1- to 5-day) incubation period. The primary lesion occurs on the genitalia and forms a superficial or deep erosion with surrounding erythema and edema. Marked unilateral and regional lymphadenopathy are present and eventually suppurate, causing buboes in untreated cases. The organisms are arranged like “schools of fish” and are found on smears from active lesions. Treatment consists of a sulfonamide such as sulfisoxazole or third-generation cephalosporin.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:158–159.
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25. The pictured skin lesion developed over a 4-week time period. The most likely diagnosis is
A) melanoma
B) basal cell carcinoma
C) keratoacanthoma
D) dermatofibroma
E) molluscum contagiosum
View Answer
25. The answer is C. (Keratoacanthoma) Keratoacanthoma (KA) is a rapidly growing hyperkeratotic nodule with a central keratin plug. A KA typically develops over 3 to 6 weeks, in contrast to the slow growth of typical SCCs over months to years. KAs occur most commonly in areas of sun-damaged skin. KAs are clinically and histologically indistinguishable from well-differentiated SCC. The etiology of KA is not certain, however; human papillomavirus DNA has been found in some cases. KAs have also occurred in skin soon after radiation therapy. Additionally, there are syndromes of multiple KAs developing over years. There is controversy regarding whether KAs are malignant or benign. Although they resemble SCCs histologically, most spontaneously regress with scar formation. There have been reported cases of invasive KAs, some with metastases, leading many experts to consider all KAs a form of SCC and treat them as such. Because of the uncertainty malignant potential of KAs, most are treated as well-differentiated SCC.
Shaw JC. Overview of nonmelanoma skin cancers. Up to Date, version 14.1. Accessed 5/3/06.
Keratoacanthoma (KA) is a rapidly growing hyperkeratotic nodule with a central keratin plug. A KA typically develops over 3 to 6 weeks, in contrast to the slow growth of typical squamous cell carcinomas over months to years.
P.323
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26. Which of the above audiograms represents a likely effusion behind the tympanic membrane?
A) Type A
B) Type B
C) Type C
D) Type As
E) Type Ad
View Answer
26. The answer is B. (Type B) A flattened tympanogram is represented by choices B and is associated with fluid of perforation of the tympanic membrane.
Weber PC. Etiology of hearing loss in adults. Up to Date, version 14.1. Accessed 5/3/06.
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27. A 29-year-old man presents in April with the rash shown here. The rash does not itch and has been present over the last week. A large, red area developed first, followed by a more generalized rash that is now present. Physical examination shows that the rash appears in a Christmas-tree pattern on his chest and back. The most likely diagnosis is
A) pityriasis rosea
B) tinea versicolor
C) herpes zoster
D) varicella
E) Lyme disease
View Answer
27. The answer is A. (Pityriasis rosea) Pityriasis rosea is a common papulosquamous rash that mainly occurs on the trunks of young adults during the spring and fall. The condition begins with the onset of a “herald patch” that is oval and erythematous. Usually within 2 to 10 days, a generalized rash follows. The individual lesions have fine scaling noted around their edges. In many cases a Christmas-tree pattern is seen over the back. The lesions may continue to appear for 2 to 3 weeks. Most cases resolve by 6 to 8 weeks. Pruritus is often present. The disease is not contagious. Treatment consists of oatmeal colloidal baths, calamine lotion, antihistamines, topical steroids, and ultraviolet-B treatments. Systemic steroids may be necessary for severe cases.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:134–138.
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28. A 12-year-old boy presents with a crusted honey-brown lesion that affects his cheek. The rash began as red macules 3 days earlier. The best treatment is
A) intramuscular ceftriaxone
B) topical hydrocortisone cream
C) oral ciprofloxacin
D) topical mupirocin ointment
E) oral acyclovir
View Answer
28. The answer is D. (Impetigo) Impetigo is caused by group A β-hemolytic streptococci or Staphylococcus aureus and typically affects young children. The lesions begin as erythematous papules that expand to form crusted patches with a honey-brown appearance. More severe cases may cause bullae to form. The infection occurs more commonly around the nose and mouth and in the intertriginous areas; there are no constitutional symptoms. Examination is usually made on clinical presentation. Treatment for mild infections includes 2% topical mupirocin ointment. More severe cases respond to dicloxacillin, cephalexin, or erythromycin. Impetigo is highly contagious. Glomerulonephritis is a rare complication of impetigo that is caused by certain strains of Streptococcus.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:15.
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29. A 65-year-old woman presents to your office complaining of gradually increasing dyspareunia. Findings from the physical examination are pictured here. The most likely diagnosis is
A) yeast vaginitis
B) herpes genitalis
C) lichen sclerosis
D) vitiligo
E) contact dermatitis
View Answer
29. The answer is C. (Lichen sclerosis) Lichen sclerosis is caused by thinning of the vulvar skin and gives rise to itching and dyspareunia. Atrophy of the skin occurs and gives rise to a shiny whitish appearance. Diagnosis is accomplished with punch biopsy. A slight increase in squamous cell carcinoma has been found in areas that are affected with lichen sclerosis. Treatment consists of potent topical corticosteroids. In addition, a topical antifungal preparation should be used to prevent secondary yeast infections.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:380.
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30. A 45-year-old woman presents with pitting of the nails that has developed slowly over the last few months. The most likely diagnosis is
A) psoriasis
B) onychomycosis
C) hyperthyroidism
D) chronic obstructive pulmonary disease
E) scleroderma
View Answer
30. The answer is A. (Psoriasis) Pitting of the nails is associated commonly with psoriasis. Erythematous scaly plaques are usually noted on other parts of the body. Thirty percent of patients with psoriasis have a positive family history for the condition. Males and females are affected equally. Other conditions that are related to nail pitting include alopecia areata and eczematous dermatitis. Chronic obstructive pulmonary disease is related to clubbing. Subungual hyperkeratosis is associated with onychomycosis.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:283.
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31. A sexually active 24-year-old woman presents to your office complaining of vaginal discharge. Findings from a wet prep are pictured here. The most likely diagnosis is
A) yeast vaginitis
B) Gardnerella infection
C) Trichomonas infection
D) gonorrhea
E) chlamydia
View Answer
31. The answer is A. (Yeast vaginitis) Yeast vaginitis causes approximately one-third of all vaginal infections. Risk factors include pregnancy, diabetes, use of intrauterine devices, recent antibiotic use, immune deficiency, or corticosteroid use. Diagnosis is made by examination of a vaginal smear under high-power microscopy after potassium hydroxide has been added. Budding yeast and pseudohyphae are noted. Topical antifungals are effective, as are single-dose oral antifungals.
Goodheart HP. A Photoguide of Common Skin Disorders: Diagnosis and Management. Philadelphia: Lippincott Williams & Wilkins; 1999:377.
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32. The sample shown here was obtained from a penile lesion of a 24-year-old sexually active male. A Tzanck smear was performed. The confirmed diagnosis is
A) gonorrhea
B) chancroid
C) herpes genitalis
D) syphilis
E) Chlamydia
View Answer
32. The answer is C. (Herpes genitalis) Tzanck smears are used in the diagnosis of herpes infections. The preparation detects multinucleated giant cells. A sample obtained from unroofed vesicles that have appeared within 24 hours provides the best specimen for diagnosis. A #15 blade is used to scrape the base of the vesicle, and the material is spread onto a slide and allowed to dry. Giemsa's, Wright's, or methylene blue is used to stain the cells. After staining, the sample is gently flooded with tap water to remove excess stain. Oil immersion is used for viewing with the microscope.
Goodheart HP. A Photoguide of Common Skin Disorders: Diagnosis and Management. Philadelphia: Lippincott Williams & Wilkins; 1999:379.
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33. An 18-year-old surfer presents with the above skin condition. The most likely diagnosis is
A) pityriasis rosea
B) secondary syphilis
C) seborrheic dermatitis
D) eczema
E) tinea versicolor
View Answer
33. The answer is E. (Tinea versicolor) Tinea versicolor is a common skin infection caused by the organism Pityrosporum orbiculare (also known as Malessezia furfur, Pityrosporum ovale, or Malassezia ovalis). The condition usually affects adolescents and young adults in tropical environments. The organism is a yeast that is a constituent of the normal skin flora. A number of factors may trigger conversion to the mycelial or hyphal form that is associated with clinical disease, including hot and humid weather, use of topical oils, hyperhidrosis, and immunosuppression. Tinea versicolor usually responds to medical therapy, but recurrence is common and long-term preventative treatment may be necessary. Versicolor refers to the variety and changing shades of colors present in this condition. Lesions can be hypopigmented, light brown, or salmon-colored macules. A fine scale is often noted, especially after scraping. Individual lesions are typically small, but frequently coalesce to form larger lesions. Typically the lesions are limited to the outer skin, most commonly on the upper trunk and extremities, and are less common on the face and intertriginous areas. Most patients are asymptomatic; however, some may complain of mild pruritus. The condition may occur in patients who are immunocompromised. It is most evident in the summer because the organism produces a substance which inhibits pigment transfer to keratinocytes, thus making infected skin more demarcated from uninfected, evenly pigmented skin. The diagnosis of tinea versicolor is made by microscopic examination of skin samples with 10% potassium hydroxide (KOH). Both hyphae and spores are evident in a pattern that is often described as “spaghetti and meatballs.” The differential diagnosis includes seborrhea, eczema, pityriasis rosea, and secondary syphilis. Seborrheic lesions are more frequently located on the central trunk, are more erythematous, and have thicker scales. With eczema, patients usually have more scaling, pruritus, and involvement of the extremities. Patients with pityriasis usually have a herald patch, more peripheral scale around border lesions, confinement of lesions to the central trunk, and the lesions do not show hyphae on KOH prep. Secondary syphilis usually involves the hands and feet, and the lesions do not show hyphae on KOH prep. Topical antifungal therapy given for 2 weeks is the treatment of choice for patients with mild and limited disease. Virtually any topical anti-yeast preparation can be used with cure rates exceeding 70% to 80%. Patients should be informed that the healing process continues after the treatment is complete. A return to normal pigmentation may take months after the completion of successful treatment. Oral medications are more convenient for patients with extensive disease and also may be more effective in patients with recalcitrant infection. Most oral antifungal agents, with the exception of griseofulvin or terbinafine, may be used. Additionally, ketoconazole 2% shampoo in a single application or daily for 3 days may be considered as an option for treatment, especially with mild infections.
Goldstein BG, Goldstein AO. Tinea versicolor. Up to Date, version 14.1. Accessed 5/3/06.
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34. The most likely diagnosis is
A) pearly papule
B) basal cell carcinoma
C) molluscum contagiosum
D) squamous cell carcinoma
E) keratoacanthoma
View Answer
34. The answer is B. (Basal cell carcinoma) The clinical presentation of basal cell carcinoma (BCC) can be divided into the following three groups:
· Nodular: The most common form of BCC. It typically presents on the face as a pink or flesh-colored papule. The lesion usually has a pearly or translucent quality and a telangiectatic vessel is frequently seen within the papule. Ulceration is frequent, and the term rodent ulcer refers to these ulcerated nodular BCCs.
· Superficial: The second most common subtype. Superficial BCC is most likely to occur on the trunk of the affected patient. The lesion typically presents as a slightly scaly papule or plaque that is most often pale red in color; the lesion may be atrophic in the center and usually is surrounded with fine translucent micropapules. Men are more likely to be affected.
· Morpheaform: Also known as sclerosing BCC, this is the least common subtype. These lesions are typically smooth, flesh-colored, or very lightly erythematous papules or plaques that are frequently atrophic; they usually have a firm or indurated quality with ill-defined borders. Some experts categorize morpheaform, infiltrative, and micronodular as “aggressive-growth” BCC, because they behave similarly. Infiltrative and micronodular BCCs are less common than the morpheaform BCC.
Wrone DA, Stern RS. Epidemiology and clinical features of basal cell carcinoma. Up to Date, version 14.1. Accessed 5/3/06.
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35. The eye findings pictured (at left) were seen in a 40-year-old woman who presented to the emergency room complaining of palpitations. The most likely diagnosis is
A) scleroderma
B) Graves’ disease
C) amyloidosis
D) Cushing's disease
E) lupus erythematosus
View Answer
35. The answer is B. (Graves' disease) Exophthalmos can be related to hyperthyroidism (i.e., Graves' disease). Patients with hyperthyroidism may report nervousness, tremor, weight loss, hair loss, palpitations, tachycardia, and muscle weakness. Pretibial myxedema is also seen in those with Graves' disease. The eye findings are related to edema and lymphoid infiltration of the orbital tissue. Unfortunately, exophthalmos usually does not resolve after treatment.
Goodheart HP. A Photoguide of Common Skin Disorders: Diagnosis and Management. Philadelphia: Lippincott Williams & Wilkins; 1999:344.
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36. An 18-year-old woman presents to your office complaining of tender nodules that have developed on the lower extremities. She has no other symptoms. She continues with her oral contraceptives but has not started any new medications. She denies any fevers and has no history of recent trauma. The likely diagnosis is
A) erythema multiforme
B) erythema nodosum
C) Lyme disease
D) pyoderma gangrenosum
E) rheumatoid arthritis
View Answer
36. The answer is B. (Erythema nodosum) Erythema nodosum is an acute inflammatory reaction of the subcutaneous fat. Women between the ages of 20 and 30 years are most likely to be affected. Causes include use of oral contraceptives or sulfonamides, pregnancy, sarcoidosis, histoplasmosis, tuberculosis, inflammatory bowel disease, lymphoma, leukemia, Behçet's disease, and streptococcal infections. Up to 40% of cases may be idiopathic. Typically, the lesions begin as bright red, tender nodules. The lesions tend to occur bilaterally on the lower extremities and occasionally on the arms. Constitutional symptoms (fever, arthralgias, and malaise) may also be present. The lesions become dark brown or violaceous during the resolution phase. Spontaneous resolution occurs in 3 to 6 weeks after onset regardless of the cause. Treatment consists of symptomatic treatment, nonsteroidal anti-inflammatory drugs, and systemic corticosteroids once an infectious cause is ruled out.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:109.
Erythema nodosum is an acute inflammatory reaction of the subcutaneous fat. Women between the ages of 20 and 30 years are most likely to be affected. Causes include use of oral contraceptives or sulfonamides, pregnancy, sarcoidosis, histoplasmosis, tuberculosis, inflammatory bowel disease, lymphoma, leukemia, Behçet's disease, and streptococcal infections. Up to 40% of cases may be idiopathic.
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37. A 26-year-old man is seen for an upper respiratory infection. After removing his shirt, you notice the lesions shown here. He reports that his father has similar lesions. The differential diagnosis should include
A) hypothyroidism
B) Addison's disease
C) multiple sclerosis
D) neurofibromatosis
E) Gardner's syndrome
View Answer
37. The answer is D. (Neurofibromatosis) Neurofibromatosis is also referred to as von Recklinghausen's disease. It is associated with autosomal-dominant inheritance and is characterized by multiple, macular, pigmented skin lesions called café au lait spots and skin tumors called neurofibromas. Axillary or inguinal freckling (Crowe's sign) is considered to be pathognomonic for neurofibromatosis. Ocular lesions (Lisch nodules) are asymptomatic, pigmented iris hamartomas that are seen in 80% of cases. The disease has been associated with defects on chromosomes 17 and 22. Neurofibromas may cause neurologic symptoms. Seizures, paraplegia, and mental retardation may occur secondary to the condition. Treatment consists of surgical removal of symptomatic or disfiguring lesions. Patients should be monitored for the development of neurofibrosarcomas, optic gliomas, acoustic neuromas, and pheochromocytomas. Those who are affected should also receive genetic counseling.
Goodheart HP. A Photoguide of Common Skin Disorders: Diagnosis and Management. Philadelphia: Lippincott Williams & Wilkins; 1999:338–339.
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38. A 2-year-old girl is brought in by her mother. The child has an erythematous rash that is recurrent and affects the backs of the legs. The most likely diagnosis is
A) ichthyosis vulgaris
B) scabies
C) atopic dermatitis
D) dyshidrotic eczema
E) tinea corpora
View Answer
38. The answer is C. (Atopic dermatitis) Atopic dermatitis is also referred to as atopic eczema. The condition is associated with erythematous pruritic areas that occur in association with hay fever, asthma, allergic rhinitis, or allergic sinusitis. The flexor surfaces are commonly involved. The course is variable with flares and remissions. The condition affects children and adults. The diagnosis is made based on history and clinical presentation. Treatment consists of topical steroids, antihistamines, tar baths and ointments, and Burrow's solution. Severe cases may require systemic steroids, cyclosporine, or phototherapy.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:78.
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39. Appropriate management of the lesion shown here includes
A) cryotherapy
B) electrodesiccation and curettage
C) shave biopsy
D) excisional biopsy
E) laser ablation
View Answer
39. The answer is D. (Malignant melanoma) Malignant melanoma lesions are treated with surgical excision. Biopsies must include epidermis, dermis, and subcutaneous fat. Shave biopsy should not be done. Knowledge of depth of invasion is essential for proper staging and treatment. Melanoma in situ (epidermal only) should be removed with margins of 0.5 cm. Melanoma that is <1.5 mm deep should be removed with a margin of 1 cm. Lesions that are 1.51 to 4 mm deep should have 1- to 2-cm margins. Lesions deeper than 4 mm should have a margin of 2 to 3 cm. Lymph node dissection is indicated if metastasis is suspected or if the lesion is of intermediate depth. Sentinel node biopsy is increasingly used in patients with proven melanoma that is >1 mm deep.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:346.
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40. The most common etiologic agent that gives rise to the condition shown here is
A) Trichophyton rubrum
B) Candida albicans
C) Epidermophytin floccosum
D) Aspergillus flavus
E) Candida glabrata
View Answer
40. The answer is A. (Trichophyton rubrum) Onychomycosis is usually caused by Trichophyton rubrum. Diagnosis is generally made by clinical presentation; however, fungal elements can be confirmed with observation under a microscope using potassium hydroxide 10% preparation of nail plate scales. Nail clippings can also be used for culture.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:282.
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41. A 45-year-old man presents with a chronic, mildly pruritic and scaly erythematous rash. The most likely diagnosis is
A) cutaneous T-cell lymphoma
B) psoriasis
C) eczema
D) tinea versicolor
E) lichen planus
View Answer
41. The answer is B. (Psoriasis) Psoriasis typically involves the scalp (including the postauricular regions), the extensor surface of the extremities (particularly elbows and knees), the sacral area, buttocks, and penis. The nails, eyebrows, axillae, umbilicus, or anogenital region may also be affected. Occasionally the disease is generalized. Typical lesions are well demarcated, variously pruritic, ovoid or circular, erythematous papules or plaques covered with overlapping thick silver appearing, slightly opalescent shiny scales. Papules sometimes extend and coalesce to produce large plaques in annular patterns. The lesions heal without scarring, and hair growth is usually unaltered. Nail involvement occurs in 30% to 50% of patients and may clinically resemble a fungal infection, with stippling, pitting, fraying, discoloration or separation of the distal and lateral margins of the nail plate (onycholysis), and thickening, with hyperkeratotic material under the nail plate.
Beers MH, et al. The Merck manual of diagnosis and therapy, 18th ed. Whitehouse Station, NJ: Merck Research Laboratories; 2006:965–969.
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42. A 4-year-old boy is brought to your office by his parents. They are concerned about the multiple skin lesions that have been present since infancy. You explain that the lesions can be a sign for
A) dysplastic nevi syndrome
B) diabetes
C) gastrointestinal cancer
D) neurofibromatosis
E) lymphoma
View Answer
42. The answer is D. (Neurofibromatosis) Café au lait skin lesions are seen in neurofibromatosis. The lesions are medium-brown freckle-like macules distributed most commonly over the trunk, pelvis, and flexor creases of elbows and knees; they are present at birth or develop in infancy in >90% of all patients.
Beers MH, et al. The Merck manual of diagnosis and therapy, 18th ed. Whitehouse Station, NJ: Merck Research Laboratories; 2006:2378.
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43. A 68-year-old man with a history of a previous myocardial infarction presents complaining of a painful lesion noted on his foot. He has been experiencing pain in his lower legs with ambulation over the last year. The most likely diagnosis is
A) venous stasis ulcer
B) arterial ulcer
C) basal cell carcinoma
D) livedo reticularis
E) diabetic foot ulcer
View Answer
43. The answer is B. (Arterial ulcer) Arterial ulcers are usually caused by atherosclerosis in the elderly. Men are more commonly affected. Pain is common, as is claudication. Distinguishing features of arterial ulcers are their sharply defined borders and round, punched-out appearance. They tend to be smaller than venous ulcers and are usually deep enough to expose muscle or tendons. Commonly affected sites include the toes, pretibial areas, and dorsum of the feet. Patients may have signs of livedo reticularis, pallor, and cyanosis. The legs may feel cold and clammy. Decreased peripheral pulses are commonly noted. Treatment consists of alleviating underlying risk factors. Pentoxifylline can be used in some cases. Surgical evaluation should be considered.
Frankel DH. Field Guide to Clinical Dermatology. Philadelphia: Lippincott Williams & Wilkins; 1999:173–174.
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44. A 42-year-old man presents with a small lump that has formed on his scalp. The most likely diagnosis is
A) syringoma
B) cylindroma
C) trichoepithelioma
D) histiocytoma
E) dermatofibroma
View Answer
44. The answer is B. (Cylindromas) Cylindromas appear as numerous smooth, rounded tumors that occur in various sizes on the scalp. They have the appearance of a group of grapes. Rarely, the tumors cover the entire scalp and are referred to as turban tumors. Cylindromas are considered benign and can be observed.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:352.
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45. A 58-year-old woman presents to your office complaining of a clear fluid-filled cyst that has formed over the distal knuckle of the fifth finger of the right hand. The most likely diagnosis is
A) epidermoid cyst
B) sebaceous cyst
C) mucous cyst
D) lipoma
E) synovial cyst
View Answer
45. The answer is E. (Synovial cyst) A synovial cyst appears as a translucent, pea-sized cyst that commonly forms adjacent to the joints of the fingers. The cysts form as a result of small tracts that lead from the synovial space of joints to the surface of the skin. The fluid contained is synovial fluid. Occasionally, the cysts spontaneously resolve. Aspiration can be attempted, but care must be taken not to introduce infection into the joint. Compression of the area after aspiration may help to prevent recurrence.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:329.
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46. Which of the following conditions is associated with the skin finding shown here?
A) Vitamin B12 deficiency
B) Hypothyroidism
C) Human immunodeficiency syndrome
D) Periodontitis
E) Gastroesophageal reflux
View Answer
46. The answer is C. (Human immunodeficiency syndrome) Oral hairy leukoplakia is a marker for human immunodeficiency syndrome and is thought to be caused by the Epstein-Barr virus. The condition appears as white plaques that have the look of corrugated cardboard. The lesions are fixed and not friable and appear on the lateral surface of the tongue. Although the condition rarely causes symptoms, burning of the tongue can occur. Treatment consists of acyclovir, topical tretinoin, and podophyllin. Oral hairy leukoplakia can be distinguished from oral candidiasis by the fact that the latter scrapes off easily with a tongue blade. Oral candidiasis typically affects the dorsal aspect of the tongue and buccal mucosa.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:195.
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47. A 3-year-old child who attends daycare is brought in by her mother with the lesions shown here noted on the abdomen. The mother reports some low-grade fevers, and the child has not been as active as usual. The most likely diagnosis is
A) impetigo
B) coxsackievirus
C) adenovirus
D) varicella
E) scarlatina
View Answer
47. The answer is D. (Varicella) Varicella (chickenpox) is described as “dew drops on rose petals” in its appearance. The lesions are red macules that progress rapidly from papules to vesicles, pustules, and then crusted lesions. The lesions are intensely pruritic. Lesions affect the entire body and oral mucosa, especially the palate. A characteristic feature is multiple lesions in varying stages of development and healing. A Tzanck smear can be helpful in confirming the diagnosis. Treatment is usually supportive but can include the use of acyclovir. Aspirin should be avoided because of the risk of developing Reye's syndrome. Varicella vaccine is recommended for all children at 12 to 18 months of age.
Goodheart HP. A Photoguide of Common Skin Disorders: Diagnosis and Management. Philadelphia: Lippincott Williams & Wilkins; 1999:106–109.
Varicella (chickenpox) is described as “dew drops on rose petals” in its appearance. The lesions are red macules that progress rapidly from papules to vesicles, pustules, and then crusted lesions.
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48. A 42-year-old man complains of multiple red lesions that have formed on his chest and abdomen. The most likely diagnosis is
A) scabies
B) chigger bites
C) granuloma annulare
D) cherry angiomas
E) erythroderma
View Answer
48. The answer is D. (Cherry angiomas) Cherry angiomas are common asymptomatic lesions that appear red in color and blanch with pressure. The diagnosis is clinical. They are more common in elderly patients. They occur more commonly on the trunk and are benign.
Frankel DH. Field Guide to Clinical Dermatology. Philadelphia: Lippincott Williams & Wilkins; 1999:120–121.
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49. A 36-month-old immigrant child is brought in by his mother with a sore throat and an erythematous, pruritic rash that has developed over the last 24 hours. The most likely diagnosis is
A) varicella
B) scarlatina
C) fifth disease
D) Rocky Mountain spotted fever
E) Measles
View Answer
49. The answer is A. (Varicella) The manifestations of varicella in most children generally develop within 15 days after the exposure and typically include a prodrome of fever, malaise, or pharyngitis, followed by the development of a generalized vesicular rash, usually within 24 hours. The lesions are commonly pruritic and appear as groups of vesicles over a 3 to 4 day period. The patient with varicella typically has lesions in different stages of development on the face, trunk, and extremities. New lesion formation generally stops within 4 days, and most lesions have fully crusted by day 6 in normal hosts.
Straus SE, Ostrove JM, Inchauspe G, et al. NIH conference. Varicella-zoster virus infections. Biology, natural history, treatment, and prevention. Ann Intern Med. 1988;108:221.
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50. A 42-year-old African American presents to your office with the above skin condition. She has a history of chronic sarcoidosis and has experienced multiple exacerbations. The most likely diagnosis is:
A) lupus pernio
B) erythema nodosum
C) erythema marginatum
D) erythema multiforme
E) psoriasis
View Answer
50. The answer is A. (Lupus pernio) Lupus pernio is associated with chronic sarcoidosis and consists of indurated plaques associated with discoloration of the nose, cheeks, lips, and ears. The lesion is more common in African American women. The nasal mucosa is frequently involved. Lupus pernio is often associated with bone cysts and pulmonary fibrosis. The course of the disease with lupus pernio is prolonged; spontaneous remissions are rare.
Joint statement of the American Thoracic Society (ATS), the European Respiratory Society (ERS) and the World Association of Sarcoidosis and Other Granulomatous Disorders (WASOG): ATS guidelines: Statement on sarcoidosis. Up to Date, version 14.1, http://uptodateonline.com. Accessed 5/08/06.
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51. A 33-year-old woman presents with complaints of recurrent rashes under the arm that come and go and the development of painful cysts with scar tissue formation. The most likely diagnosis is
A) hidradenitis suppurativa
B) reaction to antiperspirant
C) impetigo
D) tinea corpora
E) scrofuloderma
View Answer
51. The answer is A. (Hidradenitis suppurativa) Hidradenitis suppurativa is a painful, erythematous, and nodular condition that affects the axilla, genitalia, and perianal areas. Hallmarks for the disease include open comedones, enlarged follicular orifices, and scarring. Nodules become inflamed and pus filled, rupture, drain pus and blood, and then cause scarring. Sinus tracts can form. The disease often waxes and wanes. Staphylococcus bacteria is frequently the causative agent. Treatment consists of appropriate antibacterial agents based on culture and sensitivities. Intralesional corticosteroids can also be used to reduce the inflammatory response. For severe cases, excision and skin grafting may be necessary. The condition may regress as the patient approaches middle age.
Frankel DH. Field Guide to Clinical Dermatology. Philadelphia: Lippincott Williams & Wilkins; 1999:135–136.
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52. A 38-year-old African American presents with the lesion shown here. The lesion shows a “milk-white” fluorescence with a Wood's light examination. The most likely diagnosis is
A) tinea versicolor
B) tinea corpora
C) amelanotic melanoma
D) vitiligo
E) leprosy
View Answer
52. The answer is D. (Vitiligo) Vitiligo is a disorder associated with depigmentation of the skin that is thought to be related to an autoimmune-mediated loss of melanocytes. Fifty percent of those who are affected have a family history of vitiligo. The lesions appear as hypopigmented chalk-white lesions and are more obvious on people who have dark complexions. The condition is bilateral and symmetric in appearance and typically forms around orifices (i.e., mouth, eyes, nose, and anus). Vitiligo is often cyclical. Some may experience partial repigmentation. Diagnosis is made clinically. A Wood's light examination reveals a “milk white” fluorescence over the lesion. Treatment is limited, but includes potent topical steroids, psoralen plus ultraviolet A photochemotherapy, minigrafting, and cosmetics to hide areas.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:242.
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53. A 42-year-old Native American presents to your office complaining of dark spots on her face. Her medical history is unremarkable except for two previous uncomplicated pregnancies. She is now taking oral contraceptives. The most likely diagnosis is
A) solar lentigo
B) melasma
C) sunburn
D) lupus erythematosus
E) scleroderma
View Answer
53. The answer is B. (Melasma) Melasma, also referred to as chloasma, is described as the “mask of pregnancy.” The condition typically affects women with dark complexions and appears as hyperpigmentation of the skin, usually associated with the face. It is caused by long-term sun exposure, pregnancy, and oral contraceptives. In many cases the condition is idiopathic. Diagnosis is made clinically. Treatment involves the use of bleaching creams, hydroquinone, and chemical peels for more resistant cases. In some instances the condition disappears after pregnancy or the discontinuation of oral contraceptives.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:242.
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54. A 36-year-old indigent man from Mexico presents with 1-mm bluish-white macules with an erythematous oral mucosa. Two days later, an erythematous, generalized papular rash develops. The rash began on his forehead and progressed to involve his entire body. He has also had upper respiratory symptoms and a fever. The most likely diagnosis is
A) human immunodeficiency virus
B) coxsackievirus
C) rubella
D) rubeola
E) scarlet fever
View Answer
54. The answer is D. (Rubeola) Rubeola, or measles, is caused by a ribonucleic acid virus that invades the respiratory epithelium of the oropharynx. Transmission occurs via a respiratory aerosol route. The condition begins with a respiratory illness prodrome (cough, coryza, and conjunctivitis—the “3 Cs”) followed by discrete erythematous macules and papules that coalesce. Pruritus is usually absent. The rash lasts for up to a week and resolves with desquamation. Koplik's spots are described as 1-mm bluish-white macules that form on the oral mucosa (especially the buccal mucosa opposite the molars) 2 days before the onset of the generalized rash. The rash typically begins on the forehead or behind the ears and then spreads centrally to involve the face, trunk, arms, and legs. Pneumonia is the most common complication. No specific therapy is indicated for measles. Most cases resolve within 2 weeks. Vitamin A may decrease morbidity and mortality in severe cases. Immunization is recommended for all children who are 15 months or older.
Goodheart HP. A Photoguide of Common Skin Disorders: Diagnosis and Management. Philadelphia: Lippincott Williams & Wilkins; 1999:120–122.
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55. The most likely cause for the condition shown here is
A) herpes virus
B) coxsackievirus
C) adenovirus
D) Lyme disease
E) syphilis
View Answer
55. The answer is B. (Coxsackievirus) Hand-foot-and-mouth disease is caused by coxsackievirus A16. Outbreaks commonly affect children 1 to 5 years of age during the summer or early fall. Transmission occurs via a fecal-oral route. The rash appears as shallow erosions that affect the oral mucosa. The lesions are painful and can interfere with eating. The oral lesions are followed by an exanthem that consists of oval or angulated fluid-filled vesicles that form on the palms and soles. In contrast to most viral illnesses, lymphadenopathy is minimal or absent. The diagnosis is made clinically. Cultures to confirm the infection can be obtained from the throat or stool. Treatment is supportive.
Goodheart HP. A Photoguide of Common Skin Disorders: Diagnosis and Management. Philadelphia: Lippincott Williams & Wilkins; 1999:110–111.
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56. Based on the electrocardiographic (ECG) tracing shown here, the most likely diagnosis is
A) atrial fibrillation
B) left bundle branch block
C) third-degree heart block
D) inferior ischemia
E) left ventricular hypertrophy
View Answer
56. The answer is D. (Inferior ischemia) The inferior surface of the heart is usually supplied by the right coronary artery (right dominant coronary circulation). Occasionally, the inferior aspect is supplied by the circumflex artery, which branches to form the posterior descending artery (left dominant coronary circulation). Arterial occlusion related to the right coronary artery gives rise to inferior ischemic changes noted on ECG. These findings include ST-segment depression in leads II, III, and aVF.
Topol EJ, ed. Textbook of cardiovascular medicine. Philadelphia: Lippincott Williams & Wilkins; 1998:1569.
Arterial occlusion related to the right coronary artery gives rise to inferior ischemic changes noted on ECG. These findings include ST-segment depression in leads II, III, and aVF.
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57. A 67 year old collapses in your office and the following ECG strip is obtained. The correct diagnosis is
A) atrial fibrillation
B) ventricular fibrillation
C) supraventricular tachycardia
D) ventricular tachycardia
E) atrioventricular dissociation
View Answer
57. The answer is D. (Ventricular tachycardia) Ventricular tachycardia (VT) is defined as three or more successive ventricular complexes. Non-sustained VT is a series of repetitive ventricular beats which have a duration of <30 seconds, whereas sustained VT lasts >30 seconds. Typically, the rate of VT is >100 beats per minute, but may vary significantly. The rhythm is usually regular, although there may be slight irregularity of the RR intervals. The morphology of the QRS complex during VT is usually different when compared to the sinus beat. The QRS axis is typically shifted, often to the left but occasionally to the right. The width of the QRS complex is generally >0.16 sec. The VT is monomorphic when all of the QRS complexes of an episode are identical. When the QRS complexes show markedly different morphologies, the VT is said to be polymorphic and the RR intervals may be grossly irregular.
Podrid PJ. ECG tutorial: Ventricular arrhythmias. Up to Date, version 14.1. Accessed 5/11/06.
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58. A 9-year-old boy is brought into your office after a weekend camping trip. He complains of a pruritic rash that has developed over the last 24 hours. The most likely diagnosis is
A) poison ivy
B) erythema multiforme
C) lichen sclerosis
D) varicella
E) herpes zoster
View Answer
58. The answer is A. (Poison ivy) Intense pruritus and erythema are the most common presenting signs of poison ivy dermatitis. Patients develop papules, vesicles, and/or bullae, often arranged in characteristic linear or streak-like patterns where the plant has made contact with the skin. Symptoms of poison ivy in sensitized individuals generally develop within 4 to 96 hours after exposure and peak between 1 and 14 days after exposure. New lesions can present up to 21 days after exposure in previously unexposed individuals. Lesions may occur at different points in time depending on the degree of exposure to different points on the skin and the thickness of the exposed skin. This may give the impression that the poison ivy is spreading from one region to another. Blister fluid is not antigenic and is not responsible for spreading the rash. Patients may, occasionally, carry the dried antigenic resin on clothing or under fingernails, thus spreading their own dermatitis or exposing household or other contacts. Without treatment, poison ivy dermatitis usually resolves in 1 to 3 weeks. The most common complication of poison ivy dermatitis is secondary bacterial infection of the skin with Staphylococcus aureus or β-hemolytic group A Streptococcus. Bacterial infections can be polymicrobial.
McGovern TW. Dermatoses due to plants. In: Bolognia JL, Jorizzo JL, Rapini RP, et al., eds. Dermatology. New York: Mosby; 2003:274.
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59. Please identify the rhythm shown here.
A) atrial fibrillation
B) atrial flutter
C) supraventricular tachycardia
D) ventricular fibrillation
E) ventricular tachycardia
View Answer
59. The answer is E. (Ventricular tachycardia) Ventricular tachycardia is a potentially life-threatening event. ECG changes show wide QRS complexes with no discernible P waves. The rate is >120 bpm. The patient may report palpitations, dizziness, or syncope, or circulatory collapse may occur. Asymptomatic (isolated) ventricular tachycardia is usually not treated. Sustained ventricular tachycardia can degenerate to ventricular fibrillation. Hypotensive ventricular tachycardia requires immediate treatment with synchronized direct current (DC) shock. Lidocaine is used for drug treatment. Antiarrhythmics may be needed to prevent recurrent ventricular tachycardia.
Topol EJ, ed. Textbook of cardiovascular medicine. Philadelphia: Lippincott Williams & Wilkins; 1998:1767.
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60. A 65 year old presents to the emergency room complaining of palpitations. Findings from an ECG are shown here. The most likely diagnosis is
A) acute myocardial infarction
B) atrial fibrillation
C) supraventricular tachycardia
D) ventricular fibrillation
E) ventricular tachycardia
View Answer
60. The answer is B. (Atrial fibrillation) Atrial fibrillation is frequently seen in the offices of family physicians. ECG findings include the absence of obvious P waves and the irregularly irregular response of QRS complexes. Intra-atrial contractions may show rates of >350 bpm. The ventricular rate may vary depending on the atrioventricular nodal conduction but typically is elevated. Treatment involves the management of underlying causative disorders, control of ventricular rate, restoration of sinus rhythm if possible, and prevention of systemic emboli.
Topol EJ, ed. Textbook of cardiovascular medicine. Philadelphia: Lippincott Williams & Wilkins; 1998:1678.
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61. A 38 year old presents to the emergency room complaining of palpitations and shortness of breath. The most likely diagnosis based on the ECG findings shown here is
A) atrial fibrillation
B) supraventricular tachycardia
C) ventricular fibrillation
D) ventricular tachycardia
E) Wolff-Parkinson-White (WPW) syndrome
View Answer
61. The answer is B. (Supraventricular tachycardia) Supraventricular tachycardia is often referred to as narrow complex tachycardia. The condition is characterized by sustained tachyarrhythmia with a QRS complex that appears normal and has a duration >120 msec. Patients whose condition is unstable should receive immediate synchronized cardioversion. Those who are hemodynamically stable can be treated with vagal maneuvers (Valsalva, cough, carotid massage), adenosine, verapamil, or diltiazem. One should make sure that the patient does not have ventricular tachycardia, because calcium channel blockers are contraindicated.
Topol EJ, ed. Textbook of cardiovascular medicine. Philadelphia: Lippincott Williams & Wilkins; 1998:1735.
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62. A 68-year-old man is found unresponsive. An initial ECG tracing is shown here. Which of the following conditions is present?
A) Atrial ventricular dissociation
B) Ventricular tachycardia
C) Ventricular fibrillation
D) Sinus tachycardia
E) Asystole
View Answer
62. The answer is B. (Ventricular tachycardia) Ventricular tachycardia is a potentially life-threatening event. ECG changes show wide QRS complexes with no discernible P waves. Hypotensive ventricular tachycardia requires immediate treatment with synchronized DC shock. Lidocaine is used for drug treatment. Antiarrhythmics may be needed to prevent recurrent ventricular tachycardia.
Topol EJ, ed. Textbook of cardiovascular medicine. Philadelphia: Lippincott Williams & Wilkins; 1998:1773.
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63. Please identify the condition shown here.
A) Hypothermia
B) WPW syndrome
C) Inferior myocardial infarction
D) Atrial fibrillation with 3:1 block
E) Normal sinus rhythm
View Answer
63. The answer is B. (WPW syndrome) WPW syndrome is caused by an accessory pathway that links the atria and ventricles, bypassing the atrioventricular node. The ECG shows a short PR interval and slurred upstroke at the beginning of the QRS complex known as a delta wave (best seen in V2, V3, and V4). Antegrade and retrograde conduction both occur, causing a reciprocating tachycardia. Atrial fibrillation in the setting of WPW can be a medical emergency. Ventricular rates can be excessive and lead to ventricular fibrillation. DC cardioversion should be considered when atrial fibrillation is present in the setting of WPW.
Topol EJ, ed. Textbook of cardiovascular medicine. Philadelphia: Lippincott Williams & Wilkins; 1998:1738.
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64. The tympanogram shown here would support the diagnosis of
A) normal tympanic membrane
B) fluid in the middle ear
C) negative middle ear pressure
D) hypermobile tympanic membrane
E) none of the above
View Answer
64. The answer is B. (Fluid in the middle ear) Tympanograms can help assist in the diagnosis of middle ear–related problems. A flat tympanometric pattern is typical of fluid within the middle ear. The ear volume is normal, but the mobility is greatly reduced.
Spencer JP. The Academy Collection: Quick Reference Guide for Family Physicians, Children's Health. Philadelphia: Lippincott Williams & Wilkins; 2000:88–89.
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65. A 65-year-old alcoholic presents to your office with shortness of breath and generalized fatigue. An ECG is obtained. The most likely diagnosis is
A) multifocal atrial tachycardia
B) supraventricular tachycardia
C) atrial fibrillation
D) sinus tachycardia
E) pulmonary embolism
View Answer
65. The answer is C. (Atrial fibrillation) Atrial fibrillation (AF) is characterized by rapid and irregular atrial fibrillatory waves at a rate of 350 to 600 impulses/minute. This is accompanied by the presence of normal atrioventricular (AV) nodal conduction, with an irregularly irregular ventricular response of 90 up to 140 to 170 bpm; however, the rate may be higher in some patients. AF in patients with intact AV nodal conduction is associated with the following characteristics on ECG tracings: P waves are absent; fibrillatory or f waves are present at a rate that is generally between 350 and 600 bpm; the f waves typically vary in amplitude, morphology, and intervals; the R-R intervals are irregularly irregular; the ventricular rate usually ranges from 90 to 170 bpm. Ventricular rates <60 bpm are seen with atrioventricular (AV) nodal disease, drugs that affect conduction, and high vagal tone as can occur in a well-conditioned athlete. Ventricular rates >200 bpm suggest catecholamine excess, parasympathetic withdrawal, or the existence of an accessory bypass tract as occurs in the preexcitation syndrome. The QRS complexes are narrow unless AV conduction is abnormal due to functional (rate-related) aberration, preexisting bundle branch or fascicular block, or preexcitation with ventricular activation via an accessory pathway.
Arnsdorf MF. Electrocardiographic and electrophysiologic features of atrial fibrillation. Up to Date, version 14.1. Accessed 5/11/06.
Atrial fibrillation in patients with intact AV nodal conduction is associated with the following characteristics on ECG tracings: P waves are absent; fibrillatory or f waves are present at a rate that is generally between 350 and 600 bpm; the f waves typically vary in amplitude, morphology, and intervals; the R-R intervals are irregularly irregular; the ventricular rate usually ranges from 90 to 170 bpm.
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66. Based on the above ECG, the most likely diagnosis is
A) supraventricular tachycardia with 3:1 block
B) early myocardial infarction
C) incomplete right bundle branch block
D) pericarditis
E) Wolff-Parkinson-White syndrome
View Answer
66. The answer is E. (Wolff-Parkinson-White syndrome) The two major features of Wolff-Parkinson-White Syndrome (WPW) include a short PR interval (<0.12 second) and a delta wave. The QRS is wide (>0.12 second) and is considered a fusion beat. The initial part of the delta wave results from rapid depolarization of the accessory pathway. Termination of ventricular depolarization is through the normal activation pathway and gives rise to a normal appearing terminal portion of the QRS complex.
Arnsdorf MF, Podrid PJ, Burke MC. Electrocardiographic features of the Wolff-Parkinson-White Syndrome. Up to Date, version 14.1 http://uptodateonline.com accessed 5/11/06.
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67. A 4 year old is suspected of having a middle ear effusion. A tympanogram is obtained and reveals the pattern shown here. The most appropriate management is
A) tympanocentesis
B) placement of tympanostomy tubes
C) prophylactic antibiotics for 1 year
D) decongestant use for 4 to 6 weeks
E) reassurance
View Answer
67. The answer is E. (Reasurrance) A normal tympanogram curve is peaked, indicating normal mobility of the tympanic membrane. The peak compliance occurs at a pressure of -10 mm H2O (normal = +100 mm H2O to -150 mm H2O).
Spencer JP. The Academy Collection: Quick Reference Guide for Family Physicians, Children's Health. Philadelphia: Lippincott Williams & Wilkins; 2000:88–89.
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68. The tympanogram shown here was obtained on a 3-year-old girl. The likely diagnosis is
A) eustachian tube dysfunction
B) acoustic neuroma
C) middle ear effusion
D) sensorineural hearing loss
E) normal tympanogram
View Answer
68. The answer is A. (Eustachian tube dysfunction) Eustachian tube dysfunction gives rise to a tympanogram that has a normal compliance curve, but the curve is shifted to the left, indicating a negative pressure in the middle ear. The peak occurs at -200 mm H2O.
Spencer JP. The Academy Collection: Quick Reference Guide for Family Physicians, Children's Health. Philadelphia: Lippincott Williams & Wilkins; 2000:88–89.
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69. A 51-year-old man presents to your office complaining of a rash that affects the groin. Faint redness is noted, with fine scaling and no elevated border. Further examination under a Wood's lamp reveals a bright orange-coral fluorescence. The most likely diagnosis is
A) tinea cruris
B) mycoses fungoides
C) erythrasma
D) hidradenitis suppurativa
E) erysipelas
View Answer
69. The answer is C. (Erythrasma) Erythrasma looks very much like tinea cruris. It can affect the groin, axilla, and webs of the toes. The condition is caused by Corynebacterium minutissimum. The area affected fluoresces a bright reddish orange under a Wood's light. The treatment is oral or topical erythromycin.
Hall JC. Sauer's Manual of Skin Diseases, 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2000:153–154.
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70. An 18-year-old surfer presents to your office with a rash that he noted on his foot. The vesicular rash has been present over the last week and has been enlarging. The most likely diagnosis is
A) sea lice
B) cutaneous larva migrans
C) swimming pool granuloma
D) jellyfish sting
E) bathing suit dermatitis
View Answer
70. The answer is B. (Cutaneous larva migrans) Cutaneous larva migrans is also called the creeping eruption. The causative agent is a hookworm (Ancylostoma duodenale and Necator americanus). The organisms are found in the feces of dogs, cats, cattle, and monkeys. The larvae penetrate human skin (usually the feet after walking barefoot). The condition is more common in gardeners, sea bathers, plumbers, and farmers. The lesion presents as a thin erythematous, serpiginous, raised tunnel-like lesion. The larva die in 4 to 6 weeks; thus, the eruption is typically benign and self-limited. Treatment consists of topical steroids, topical or oral thiabendazole, albendazole, or liquid nitrogen.
Beers MH, Porter RS, eds. The Merck manual of diagnosis and therapy, Merck Research Laboratories, 18th ed. Whitehouse Station, NJ: Merck & Co.; 2006:993–994.