Sigmoid-Urachal-Vesical Fistula Associated with Urothelial Carcinoma in an Adult Male: Case Report

Abstract

Urachal remnants that abnormally remain patent are often subject to infection, spontaneous rupture, fistula formation or a malignant change. Sigmoid-urachal fistulas have been reported in cases of colonic diverticulitis or an infected urachal cyst (1-3); however, for these cases, there is no communication with the urinary bladder or any association with urothelial carcinoma. Although the normal urachus is most commonly lined by the transitional epithelium, an urachal carcinoma predominantly manifests as an adenocarcinoma. Urothelial carcinoma is extremely rare (4-6). We report an unusual case of a sigmoid-urachal-vesical fistula associated with urothelial carcinoma in an adult male. For accurate diagnosis and treatment planning, radiologists should consider the presence of a coexistent malignant lesion in a complicated urachal remnant. Case ReportA 45-year-old man presented to our hospital with pneumaturia and fecouria on voiding of two months duration. The patient had no prior abdominal surgeries. The vital signs were within normal limits. On a physical examination, there was focal percussion tenderness in the suprapubic region. The patient reported occasional dysuria and urgency but experienced no urinary frequency, incontinence or diminished urine stream. The patient denied having diarrhea, constipation, hematochezia, melena, and abdominal cramping. The leukocyte count was elevated at 18,600 per millimeter. Urinalysis revealed 2+ leukocyte esterase and a blood and microscopic examination demonstrated 3-5 red