Evalynn Vasquez, MD, MBA
Derek Matoka, MD
BASICS
DESCRIPTION
• Umbilical abnormalities result from failure of umbilical ring to close or persistence of umbilical structures
• Abnormalities can be classified as:
– Mass
– Infection
– Persistent drainage
• Most likely to present during the neonatal period or early infancy
EPIDEMIOLOGY
Incidence
• Most common mass at the umbilicus in an infant is granulation tissue
• Umbilical hernia: 10–20% of all infants
– Increased incidence: Premature infants (up to 75% in infants under 1500 g), females, African descent, Down syndrome, Beckwith–Wiedemann syndrome, hypothyroidism, mucopolysaccharidosis
• Omphalitis is currently extremely rare due to adequate hygiene and the use of topical antibiotics on the umbilical cord
• Persistent remnant of the vitelline duct has 2% incidence
• Urachal remnants are common but often asymptomatic (3% of adult autopsy specimens)
• Patent urachus occurs in <1/1000 live births
• Urachal carcinoma: 1 in 5 million cases annually
Prevalence
N/A
PATHOPHYSIOLOGY (1)
• The primitive umbilical cord develops with the anterior abdominal wall during weeks 2–3 of gestation
• Early in gestation, the umbilical cord contains the vitelline duct, allantois, two arteries, and one vein
• The vitelline duct is a connection between the midgut and yolk sac. It involutes in weeks 7–9 and becomes the ligament teres of the liver. This ligament attaches to the inferior portion of the umbilical ring (75%) or the superior aspect (25%)
• The bladder forms from the ventral portion of the cloaca. The bladder descends into the pelvis with the urachus connecting the bladder apex to the umbilicus. The urachus involutes to a fibrous cord becoming the median umbilical ligament
• The anterior abdominal wall progressively closes leaving only an umbilical ring
• Failure of normal development or failure of the vitelline duct, urachus, or umbilical ring to involute results in umbilical abnormalities
• The urachal remnant is represented by the median umbilical ligament in adults. Urachal remnants: Most common; comprise spectrum of anomalies:
– Patent urachus (rare, 3 in 1 million): Unobliterated urachus draining urine from the bladder to the umbilicus
– Urachal sinus: Urachus obliterated at the bladder level, but open sinus remains at the umbilicus. Drainage often is the result of episodic infections of the sinus
– Urachal cyst: Urachus obliterated proximally and distally, but unobliterated fluid-filled cyst remains in between
– Infected urachal cysts found in all ages
– Urachal diverticulum of the bladder: May result from drainage of a urachal cyst to the bladder.
• Vitelline duct remnant (omphalomesenteric duct): Connects fet al midgut to yolk sac
– Umbilical sinus, vitelline cyst, or Meckel (8%–10% of Meckel have umbilical anomaly)
• Arterial umbilical remnants
ASSOCIATED CONDITIONS
• Volvulus or internal hernia with vitelline abnormalities
• GI bleed: Meckel diverticulum
• Bladder outlet obstruction
GENERAL PREVENTION
N/A
DIAGNOSIS
HISTORY
• Most umbilical disorders are found antenatally or at birth but can have a delayed diagnosis or be found incidentally if asymptomatic
• Discharge suggests vitelline duct remnant, urachal remnant, or umbilical granuloma
• Umbilical infections are often related to hygiene issues.
– Home births have a slightly increased incidence of omphalitis.
• Painless, intermittent, self-resolving GI bleed in a young child should raise the suspicion of a Meckel diverticulum.
• Acute onset abdominal pain can suggest incarcerated umbilical hernia, volvulus or internal hernia due to fibrous vitelline remnant, or intussusception of a Meckel diverticulum.
• Urachal tumors are typically silent because of their extraperitoneal location; consequently, the majority of patients exhibit local invasion or metastatic disease at presentation.
• UTI or bladder stone can be associated with a urachal diverticulum.
PHYSICAL EXAM
• Granuloma and umbilical polyp: Small bright red remnant of intestinal or gastric mucosa
• Hernia: Non-tender reducible outpouching through umbilical ring
• Omphalitis: Tender, erythematous, bleeding, and discharge at the umbilicus
• Patent urachus: Clear fluid draining in the newborn period often exaggerated with crying or straining
• Urachal cyst: Asymptomatic and incidentally found unless associated with infection. Patient may then present with fever, voiding symptoms, midline infraumbilical tenderness, mass, or urinary tract infection. Rarely it can rupture into preperitoneal tissues or the peritoneal cavity
• Urachal sinus: May present in infancy or later with clear drainage or nonspecific periumbilical erythema
• Vesicourachal diverticulum: May present with urinary tract infections
• Vitelline umbilical fistula: Found in newborn period with the appearance of an umbilical stoma with pink, circular, intestinal remnant
• Meckel diverticulum: Asymptomatic unless bowel obstruction from intussusception occurs or GI bleed due to mucosal ulceration from acid secretion. Rule of 2’s: 2% of the population, 2 feet from the ileocecal valve, 2 inches in length, 2 types of common ectopic tissue (gastric and pancreatic), 2 yr is the most common age at clinical presentation, 2 times more boys are affected
DIAGNOSTIC TESTS & INTERPRETATION
Lab
• Urinalysis: evidence of hematuria or infection
• Check creatinine of draining umbilical fluid to determine if it could be a patent urachus
• Urine cytology may be positive in cases of urachal carcinoma
Imaging
• Ultrasound: Best tool for initial assessment. It accurately determines anatomy of umbilical structures and evaluates for bladder/small bowel communication
• VCUG: Assess for a urachal remnant and can rule out associated bladder outlet obstruction
• Fistulography/Sinogram: Catheterization of tract and injection of contrast may be difficult and unreliable. Can diagnosis vitelline umbilical fistula which will show communication to small bowel.
• Meckel scan: Specific for gastric mucosal cells and accuracy is greater than 90%
• CT or MRI of abdomen and pelvis with IV and PO contrast
– Gold standard for diagnosis and staging particularly for cancer
– Midline, calcified, partially cystic mass with local extension is concerning for but not diagnostic of urachal carcinoma.
Diagnostic Procedures/Surgery
Cystoscopy with biopsy or resection
Pathologic Findings
• Umbilical polyp: Excrescence of vitelline duct mucosa retained in the umbilicus
• 10% of bladder adenocarcinomas arise from a urachal remnant.
– Only type of bladder cancer more common in women than in men
– Urachal adenocarcinoma tends to present at an earlier age than other forms of bladder adenocarcinoma
– Histologically, urachal adenocarcinoma tends to be lower grade with improved overall 5-yr survival
– Mucin production is found in up to 75% of cases; calcification in 50–70%
DIFFERENTIAL DIAGNOSIS
• Umbilical mass
– Granuloma/umbilical polyp: Infants
– Umbilical hernia: All ages
– Urachal neoplasms: Adults
Benign (very rare): Adenomas, fibromas, fibroadenomas, fibromyomas, hamartomas
Malignant (very rare, less than 0.5% of all bladder cancers): Most adenocarcinoma
– Sister Mary Joseph nodule (adults): Umbilical metastasis of primary tumors (if primary is known, usually from genital or GI tract)
– Others: Dermoid cyst, sebum cyst, spontaneous umbilical fistula from Crohn disease/TB/perforated appendix, urachal carcinoma, and skin cancers such as basal-cell and squamous-cell carcinoma
• Infection
– Omphalitis
– Infected urachal cyst
• Drainage
– Urachal remnant:
Patent urachus (50%)
Urachal cyst (30%)
Urachal sinus (15%)
Vesicourachal diverticulum (5%)
– Vitelline remnant: Meckel diverticulum, vitelline umbilical fistula, fibrous vitelline remnant
– Endometriosis: Pain and hemorrhagic umbilical discharge during menses
TREATMENT
GENERAL MEASURES
Identify the abnormality and manage accordingly
SURGERY/OTHER PROCEDURES (2,3)
• Granuloma and umbilical polyp (infants): Very difficult to differentiate clinically. Treat with silver nitrate. If there is no response after two or three attempts, surgical excision may be necessary. Pedunculated lesions with a narrow stalk may be managed with ligation of the base with absorbable suture
• Hernia (infants): 1 cm or less, spontaneous closure likely in >90%. Hernias >2 cm typically need surgical correction after 3–4 yr of observation
• Omphalitis (infants): Broad spectrum antibiotics. Surgical debridement may be necessary. There is a high mortality rate and risk of polymicrobial necrotizing fasciitis; mortality of up to 15%
• Patent urachus: Resect entire duct via infra-umbilical incision (in newborns), or transverse mid-hypogastric incision in older children; remove cuff of bladder with specimen
• Urachal remnant: Surgical exploration with excision.
– If urachal cyst is infected, it may be treated initially with broad spectrum antibiotics and drainage.
– Complete excision can be performed once infection has subsided. Risk of malignant degeneration has been reported in the literature.
• Patent vitelline duct/ vitelline umbilical fistula (enteric contents per umbilicus): Surgical exploration with excision needs prompt laparotomy and duct excision to avoid intussusception/volvulus
• Meckel diverticulum: Surgical exploration with excision
• Urachal carcinoma
– Radical cystectomy or partial cystectomy with wide surgical margins and en-bloc resection of urachal remnant extending from bladder to umbilicus, posterior rectus sheath, and all tissue between medial umbilical ligaments is recommended for lower stage, resectable disease.
– Partial cystectomy may offer a comparable oncologic outcome and less morbidity to radical cystectomy if tumor is completely resected (4)[C]
– Failure to resect the umbilicus and positive surgical margins are associated with a worse outcome (5)[B]
• Bilateral pelvic lymph node dissection
– Should follow the standard template for bladder cancer.
– May be useful for staging but does not provide any survival advantage.
• Surgical resection is particularly well-suited to a laparoscopic or robotic approach with comparable short-term outcomes.
ADDITIONAL TREATMENT
Radiation Therapy
Limited role for unresectable urachal carcinoma
Additional Therapies
N/A
Complementary & Alternative Therapies
N/A
ONGOING CARE
PROGNOSIS
• Minimal long-term sequelae when managed appropriately
• Urachal carcinoma
– 5-yr overall survival: 27–80%; about 50% for locally advanced disease
– Less than 20% for metastatic disease
– 93% for disease confined to the urachus and bladder after surgical resection with bladder preservation
– 69% for extravesical and periurachal disease after surgical resection with bladder preservation
COMPLICATIONS
Morbidity related to the abnormality and the specific treatment modality that is utilized
Patient Resources
Urology Care Foundation: Urachal Abnormalities http://www.urologyhealth.org/urology/index.cfm?article=41
REFERENCES
1. Snyder CL. Current management of umbilical abnormalities and related anomalies. Semin Pediatr Surg. 2007;16(1):41–49.
2. Frimberger D, Kropp B. Bladder anomalies in children. In: Wein AJ, ed. Campbell-Walsh Urology. Philadelphia, PA: Saunders; 2007:3576–3579.
3. Pomeranz A. Anomalies, abnormalities, and care of the umbilicus. Pediatr Clin North Am. 2004;51(3):819–827.
4. Siefker-Radtke AO, Gee J, Shen Y, et al. Multimodality management of urachal carcinoma: the M.D. Anderson Cancer Center experience. J Urol. 2003;169(4):1295–1298.
5. Herr HW, Bochner BH, Sharp D, et al. Urachal carcinoma: Contemporary surgical outcomes. J Urol. 2007;178(1):74–78.
ADDITIONAL READING
• Christison-Lagay ER, Kelleher CM, Langer JC. Neonatal abdominal wall defects. Sem Fet al Neonatal Med. 2011;16(3):164–172.
• Ledbetter DJ. Congenital abdominal wall defects and reconstruction in pediatric surgery: gastroschisis and omphalocele. Surg Clin North Am. 2012;92(3):713–727.
• Yu J-S, Kim KW, Lee HJ, et al. Urachal remnant diseases: spectrum of CT and US findings. RadioGraphics. 2001;21:451–461.
See Also (Topic, Algorithm, Media)
• Bladder Cancer, Adenocarcinoma
• Urachal Abnormalities
• Urachal Carcinoma
CODES
ICD9
• 553.1 Umbilical hernia without mention of obstruction or gangrene
• 759.89 Other specified congenital anomalies
• 772.3 Umbilical hemorrhage after birth
ICD10
• K42.9 Umbilical hernia without obstruction or gangrene
• P51.9 Umbilical hemorrhage of newborn, unspecified
• Q89.8 Other specified congenital malformations
CLINICAL/SURGICAL PEARLS
• In the newborn, a granuloma is the most common cause of persistent drainage.
• Ultrasound is an accurate, minimally invasive initial imaging modality.
• Umbilical hernias may be seen in up to 20% of infants, but the majority will resolve by 3 yr of life.
• If surgical excision of a urachal remnant is performed, a bladder cuff should be taken if there is involvement of the dome of the bladder.