Enterovesical fistula

During a period of 18 months, 24 patients were identified with enterovesical fistula. The fistulas were colovesical in 18, ileovesical in four and rectovesical and appendicovesical in one each. Fifteen of the 23 patients in whom this information was available had pneumaturia and four had fecaluria. The standard battery of diagnostic tests for enterovesical fistulas was performed. Thirteen patients with colovesical fistulas had small intestinal series; the fistula was demonstrated in only five patients. Sixteen patients had an intravenous pyelogram and the fistula was demonstrated in none. Cystoscopy was performed upon 15 patients and the fistula was demonstrated in one. A cystogram was performed upon ten patients and the fistula was demonstrated in four. In contrast, all patients had positive computed tomographic findings. The pathognomonic finding of air within the bladder was demonstrated in 20 of 23 patients without recent transurethral instrumentation. All 24 computed tomographic scans demonstrated an abnormally thickened segment of intestine in intimate contact with a thickened bladder wall at the site of the fistula. This was associated with a paravesical mass in 23 of the patients. Two of the four patients in whom bladder air was not seen had a vesical fistula of the small intestine. All 24 fistulas were confirmed by operation (22 patients) or subsequent clinical course (two patients). These findings suggest that computed tomography is the most accurate diagnostic tool available for demonstrating enterovesical fistulas. Computed tomography should supplant the use of other less sensitive diagnostic test currently included in the evaluation of patients with a suspected enterovesical fistula.