Utilidad del renograma diurético en la detección de una fístula enteroureteral

After a 2-year-old male with left impairment underwent surgery for a left vesicoureteral stenosis, his renal function was followed up by means of dynamic renal scintigraphy with 99mTc-DTPA. Incidental radiotracer accumulation was observed in left hemiabdomen tracing the descending and sigmoid colon. A vesico-colonic fistula was suspected. However, ultrasonography and cystography studies showed no presence of a vesico-enteric fistula. Because the patient persisted without symptoms, an expectant approach was adopted. One year later, he began to suffer watery diarrhoea episodes. 99mTc-DTPA renography was again performed to re-evaluated renal function and explore presence of urinary-enteric fistula. Diuretic renography demonstrated the presence of a vesical leak to sigmoid gut, which was confirmed by recovery of fecal matter from the patient. Both isotopic renograms evidenced the presence of uretero-sigmoid fistula, an uncommon postsurgical that was not detected by cystography, ultrasonography or RMN. The patient subsequently underwent surgery for fistula repair.