[Sigmoido-buttock fistula by diverticulitis: report of a rare complication]. / Fístula sigmoideo-glútea por diverticulitis. Reporte de una rara complicación.

INTRODUCTION: The complicated diverticulitis of the colon is characterized by its association with abscesses, bleeding, stenosis, perforation, obstruction or fistula. We report a case of spontaneous sigmoido-cutaneous fistula from diverticulitis to an unusual place in the gluteal region. CLINICAL CASE: A 59-year-old male patient presented an inflammatory wound in left buttock without response to the conservative medical treatment. The fistulography, colonoscopy, barium enema and computed tomography showed a sigmoido-cutaneous fistula to the left buttock from diverticulitis. The biopsy of the lesion ruled out malignancy. We performed an elective sigmoid resection with primary colorectal anastomosis, partial fistulectomy and injection of a fibrin sealant in the residual tract. DISCUSSION: The colon-cutaneous fistulas from diverticulitis are relatively rare. We report a spontaneous fistula with origin in a single diverticulum in the sigmoid colon and that drained through the piriform fossa of the pelvic floor to the skin of the left buttock. CONCLUSIONS: A high index of suspiscion is necessary to not confuse the colo-buttock fistula with local abscesses.