The Heartbreak of Psoriasis
At the time of birth a baby’s skin is soft, smooth, and often completely clear of defects. However, as humans age and as their skin is exposed to longer periods of ultraviolet (UV) radiation (sunlight) and environmental factors, skin is likely to exhibit localized changes in coloration or in the proliferation of cells, which can result in moles, freckles, or tumors. Other skin diseases can occur, affecting the integrity of the skin and causing potential problems with other organ systems.
Acne
Acne vulgaris is a common skin disease that often begins or intensifies during adolescence because of changes in hormones that increase oil and sebum production. It arises when hair follicles and sebaceous glands become clogged and infected. As a result, pimples or pustules may manifest and continue to occur until the underlying causes of the skin disorder are relieved.
Anatomy of a Word
comedo
A comedo is also known as a blackhead. Comedones are another common problem associated with acne. While comedones occur because of dirt or material blocking the hair follicle, they can become a whitehead or pimple if they become infected.
Blisters
Blisters are common disorders that occur on the feet because of friction from walking or running in poorly fitting shoes or on the hands from using hand tools for long periods of time without gloves. These frictional forces tear and shear the cells of the stratum spinosum. This causes a separation of cells, and the plasma from blood vessels fills these voids and raises the upper layers of the epidermis. If the friction is continued and more damage occurs to the tissue, the blister may fill with blood due to vascular damage within the layers of the skin.
Nevi
Permanent and benign colored areas of the skin, often called birthmarks, are termed nevi (nevus is singular). When this condition is caused by of a proliferation of melanocytes (pigment cells), the tissue will have a brown to black coloration. If the colored tissue is caused by a collection of blood vessels close to the skin, the tissue will have a red color and is called a vascular nevus (hemangioma), or more commonly, a strawberry mark.
Moles are a form of melanocytic nevi. Freckles (ephelides) are flattened accumulations of melanocytes in a specific area typically brought about by exposure to UV radiation.
Skin Cancer
Basal cell carcinoma, the most common form of skin cancer, is caused by out-of-control growth of the cells at the basal layer of the epidermis. Exposure to UV radiation causes damage to the DNA in these cells. Instead of dividing and creating healthy new cells, damaged and diseased cells are created. Fortunately, this is a fairly slow-growing cancer and rarely spreads to other parts of the body. That being said, it can lead to disfiguring lesions if not treated.
Melanoma, while not the most common form of skin cancer, is the most dangerous. The melanocytes lose control of their division and form colored tumors on the skin that may resemble moles (or form from moles). What makes melanoma so dangerous is the fact that it may quickly spread widely throughout the body, where it becomes difficult to treat.
Squamous cell carcinoma occurs when the most superficial layers of the skin divide out of control. These tumors may appear as red patches of flaky skin or open sores, and may bleed from or near the tumor itself. Like melanoma, these tumors are mostly caused from UV exposure and damage to the cells and can be disfiguring and dangerous if not removed before the cancer can spread.
Allergic Reactions
To prevent infection, your immune system defends itself against pathogens such as viruses and bacteria, but sometimes it defends against substances that aren’t a danger to it, such as pet dander or pollen. This immune reaction can show up in your skin, causing swelling, hives (itchy red welts), and rashes (small red bumps). When the substance causing the reaction (the allergen) is removed, your body usually calms down and the reaction disappears. Severe allergic reactions can be life-threatening, although most are more moderate.
Testing for allergies
One of the ways a doctor will test for allergies is to apply the allergen or a form of the allergen to the skin (a skin patch test) or inject it just beneath the skin (intradermal test). Many common allergies are diagnosed this way.
Eczema
Eczema is the name used to refer to a group of conditions that cause red, itchy skin. Some of these conditions aren’t even related to each other. These are among the most common:
· Atopic eczema is what most people think of when they think of eczema. Also called atopic dermatitis, it causes big patches of red, itchy skin. Scientists aren’t sure what causes it, although they know it’s more common in people with allergies such as hay fever.
· Irritant dermatitis is caused by prolonged or repeated exposure to toxins.
· Scabies, which causes red, itchy skin, is a skin infection caused by mites.
· Stasis dermatitis is a skin condition of the legs caused by poor circulation.
Psoriasis
Psoriasis is a chronic (long-lasting) skin disease characterized by thick, silvery scales and dry, itchy patches of skin. It is caused by cells building up on the surface of the skin, and is the result of a problem with the life cycle of skin cells. Periods of outbreak may be followed by periods of relative calm. Treatment focuses on stopping the skin cells from growing so rapidly and on reducing the pain and itching associated with the disease.