Sigmoid colon ureteral fistula presenting with urosepsis

Abstract

This 72-year-old white male presented in the emergency room with symptoms of urosepsis. He had been sick for about ten days, reporting in-creasing malaise, temperature elevation, left flank pain, and “foul-smelling” urine. He had three prior episodes of left lower quadrant pain associated with diarrhea; which his physician had diagnosed as di-verticulitis and treated with antibiotics and dietary restrictions.At admission, vital signs of the cachec-tic patient were recorded as BP 160/78, pulse rate 92, respiration 22, and temperature of 38.4 Celsius. Physical exam demonstrated the lungs clear to aus-cultation and percussion; tenderness to percussion in the left back, and rebound tenderness in the left lower abdominal quadrant. Laboratory data were: RBC 3.8, Hb 9.4, HCT 36, WBC 24,000, BUN 28, Creatinine 2.6; K 4.2, and Na & Cl within normal limits. Urinanalysis and cytology demonstrated a murky appearance, specific gravity of 1.024, cellu-lar debris, WBC 120/hpf, RBC 80/hpf, gram negative bacteria, and vegetable fibers. An admission chest radiograph was negative.A three-phase contrast-enhanced CT (with intravenous contrast medium reduced to 60 mL, because of elevated creatinine) was performed with both coronal and sagittal reconstructions. An axial slice showed a hugely dilated left ureter with an air fluid level (Figure-1). A coronal reconstruction ( the area of interest enlarged to156%) demonstrates gas in the fistula to the thickwalled segment of the sig-moid colon as well as at the level of the UPJ (Fig-ure-2). Diverticula are shown in the third portion of the sigmoid colon. An aneurysm of the infra-renal segment of the aorta was noted. Another coronal re-construction (206% enlargement of area of interest) at a slightly more posterior level shows the entire left ureter dilated by gas (Figure-3). A sagittal re-construction shows the dilated gas-filled left ureter (Figure-4).Fistula from the GI tract to the ureter is un-common. Uretero-ileal fistulae as consequence of Crohn’s disease occur with higher frequency then uretero-colonic fistulae (1,2). Uretero-colonic fistu-lae may be secondary to inflammatory disease of the large bowel, such as diverticulitis, obstructing ureteral calculi, or neoplasm of the colon that con-tiguously involves the ureter (3,4). A non-function-ing kidney and ureter are often the consequence. CT is the modality of choice in working up uro-sepsis or renal colic, while antegrade or retrograde ureterogram is the most sensitive in the detection and characterization of a fistulous tract (5). In a like pathologic process, fistulization to the fallopian tubes can occur from diverticular abscesses. How-ever, the incidence of colo-vesical fistulae caused by diverticulitis is higher (6).