Umbilical Polyp
A healthy 4-month-old boy was seen at the pediatric clinic with a concern of bloody discharge from his umbilicus. The mother had noted a small lump within his belly button area at birth, which had increased in size after the cord separated. At a follow-up visit, his primary care physician tried cauterizing the lump 3 times, but there was no improvement.
The mother reported that the lump bleeds spontaneously with bright red blood. The bleeding was not associated with urination or defecation, but the mother had noticed that the blood sometimes was mixed with clear fluid that smelled like urine. The amount of bleeding was minimal, and there were no associated symptoms of discomfort, excessive crying, or abnormal bowel movements.
The patient was born at full term with no prenatal or postnatal complications. His growth and development were normal.
On physical examination, a 0.35 × 0.25-cm, bright red, shiny mass covered with fresh blood was located within the umbilical area. The mass was surrounded by an area of erythematous skin with no tenderness or discomfort on touch, no raised temperature, and no active bleeding.
Given the intermittent but persistent bleeding despite cauterization, the possibility of an umbilical polyp was considered. A shave biopsy showed no intestinal mucosa continuing with the epidermis, but a sonogram showed a hyperechoic area connecting to the urinary system that was consistent with a patent urachus. The patient was referred to a pediatric surgeon for possible surgical exploration and correction of the patent urachus.
During the initial developmental stages of intrauterine life, a broad communication develops between the midgut and yolk sac. With fetal growth and elongation of the intestinal tract, this communication narrows, giving way to the omphalomesenteric duct. This structure is obliterated and loses its intestinal attachment by the end of the fifth to sixth intrauterine week; together with the yolk sac remnants, it is absorbed into the umbilical cord. The umbilical cord then dries out and separates 2 to 3 weeks after delivery, and the underlying skin recovers, leaving no signs of the cord. Total or partial impairment in closure of the omphalomesenteric duct can result in a number of conditions, including umbilical enteric fistula, umbilical sinus, omphalomesenteric duct cyst, and umbilical polyp.1
An umbilical polyp is a rare congenital lesion that is among the possible developmental anomalies of omphalomesenteric duct remnants. It usually is associated with visceral connections and is composed of gastric mucosa, intestinal mucosa, and pancreatic tissues; ectopic gastrointestinal mucosa also has been reported.2 It occasionally originates from a urachal remnant.3
With an umbilical polyp, the navel region remains bright red with a granular appearance following the separation of the stump. Clinically, an umbilical polyp presents as a red, firm, round tumor with mucoid and/or bloody secretions. It bleeds easily, resists local treatment, is painless, and continues for months to years. Persistent weeping from a cord stump in infants often is a result of a patent omphalomesenteric duct.4
Umbilical polyps can be mistaken clinically for other common umbilical disorders such as umbilical granulomas and pyogenic granulomas. Umbilical granulomas are dry and velvety lesions that respond to chemical cauterization, unlike a polyp. The presence of an umbilical polyp may indicate a persistent omphalomesenteric duct, which may result in complications such as an intra-gastrointestinal connection leading to prolapse or herniation of gastrointestinal contents,5 or as in our case, a communication with the bladder resulting in persistent urinary discharge.6,7
Parents should be educated about the chemical cauterization of umbilical polyps. Persistent polyps should be further investigated with imaging and histopathologic studies. Early diagnosis of this lesion can facilitate treatment and decrease the risk from associated complications.
References
1. Khati NJ, Enquist EG, Javitt MC. Imaging of the umbilicus and periumbilical region. Radiographics. 1998;18(2):413-431.
2. Gray SW, Skandalakis JE. Embryology for Surgeons: The Embryological Basis for the Treatment of Congenital Defects. Philadelphia, PA: WB Saunders; 1972:156-167.
3. Oğuzkurt P, Kotiloğlu E, Tanyel FC, Hiçsönmez A. Umbilical polyp originating from urachal remnants. Turk J Pediatr. 1996;38(3):371-374.
4. Cullen TS. A patent omphalomesenteric duct. In: Embryology, Anatomy, and Diseases of the Umbilicus, Together With Diseases of the Urachus. Philadelphia, PA: WB Saunders; 1916:188-213.
5. Kittle CF, Jenkins HP, Dragstedt LR. Patent omphalomesenteric duct and its relation to the diverticulum of Meckel. Arch Surg. 1947;54(1):10-36.
6. Steck WD, Helwig EB. Cutaneous remnants of the omphalomesenteric duct. Arch Dermatol. 1964;90(5):463-470.
7. Lowman RM, Waters LL, Stanley HW. The roentgen aspects of the congenital anomalies in the umbilical region. Am J Roentgenol Radium Ther Nucl Med. 1953;70(6):883-910.