Gluteal-fold flap repair of rectovaginal fistula caused by aluminum potassium sulfate hydrate-tannic acid injection for internal hemorrhoids: a case report

BACKGROUND: Rectovaginal fistula (RVF) following aluminum potassium sulfate hydrate-tannic acid (ALTA) injection therapy for hemorrhoids is a rare complication. We report the first case of RVF after ALTA injection therapy successfully treated by gluteal-fold flap. CASE PRESENTATION: A 49-year-old female suffered from a fever and rectal ulcer after undergoing internal hemorrhoid treatment with a submucosal ALTA injection at a previous clinic. One week after ALTA therapy, she noted obvious passage of flatus and stool through the vagina, and was diagnosed with RVF by anoscope at another clinic. She was referred to our hospital 3 weeks after ALTA therapy. Sigmoid colostomy was performed for fecal diversion as a preliminary step for fistula repair. However, the fistula was scarred and the defect between the rectum and vagina did not improve at all. Ten months after ALTA therapy, we performed fistula repair by gluteal-fold flap. Seven months later, sigmoid-colostomy reversal was performed. The patient has experienced no RVF in the 3 years since sigmoid-colostomy reversal. CONCLUSIONS: The gluteal-fold flap strategy is a useful option for severe RVF management.