Umbilical Polyp (UP)

Abstract

The most frequent umbilical mass in neonates is the umbilical granuloma followed by the umbilical polyp; most of UP are congenital, and few entities are an acquired lesions, but we opted to discuss this pathology with the acquired lesions because of the resemblance between UP and U granuloma and to give some clues for differentiation between those different pathologies, with some shared features. After cord stump separation, the umbilical scar covered by a normal skin, any abnormal mucosal overgrowth at the umbilical base, which may result in a polypoid mass; most of literatures are describing only one type of UP, which is a remnant of the omphalomesenteric duct, but herein all possible types of UP will be classified and described. These polyps are rare abnormalities and are usually diagnosed in neonates, especially the congenital one, although lesions have been found in older children and also in adults, but in the latter they are exceptional, and it is usually neoplastic, and of course it is an acquired lesion, with a wide spectrum of different pathologies. Clinically UP presents as a small round swelling, with red, smooth surface and shiny appearance because it is mucosa, covered with serosity and located at the base of the umbilicus. Differential diagnosis of this polyp may pose difficulties, especially with umbilical granuloma because of its clinical similarity; with a more frequent presentation, granuloma is mainly distinguished by its smaller size and the good response that it presents to topical treatment, whereas in the polyp the treatment is surgical. Other entities to be differentiate from UP are persistence of urachus, omphalocele, haemangiomas and keloid umbilical scar. In UP the histopathological study of the lesion shows an abrupt transition from squamous epithelium to an intestinal, colonic or gastric glandular epithelium and less frequently pancreatic tissue. In adults, metastases from intra-abdominal tumors need to be excluded. Diagnosis of UP is usually made by physical exam, which may demonstrate a watery discharge from the umbilicus, imaging, including ultrasound, computerized tomography, fistulogram or voiding cystourethrography, which could also be useful in the diagnosis of patent urachus. Surgical excision of UP is mandatory with or without abdominal exploration to detect any other associated anomalies.