Complicated sigmoid diverticulitis causing colouterine fistula and recurring tubo-ovarian abscesses: a case report

Introduction: Diverticulitis is an inflammatory disease of the intestine that can lead to complications such as perforation, abscesses, and fistulas, including a colouterine fistula. Colouterine fistulas are rare, certainly in combination with a tubo-ovarian abscess (TOA), and the literature on this topic is scarce. Case presentation: We report the case of a 54-year old woman with recurrent intra-abdominal and tubo-ovarian abscesses and a colouterine fistula due to complicated sigmoid diverticulitis. The patient initially presented with left iliac fossa pain, fever, and altered bowel habits, without vaginal or urinary symptoms. Her medical history included a left-sided ectopic pregnancy and previous episodes of diverticulitis. Treatment consisted of intravenous (IV) antibiotics, radiological and surgical drainage, and eventually Hartmann's procedure with a salpingo-oophorectomy. Histopathology confirmed the presence of a TOA and a fistula. Discussion: This case highlights the diagnostic difficulty in distinguishing complicated diverticulitis from pelvic inflammatory disease (PID) as a cause of a TOA in the presence of a colouterine fistula, especially when CT imaging shows no signs of the fistula or of active diverticulitis. A multidisciplinary approach involving gynecology, radiology and surgery contributed to achieving a successful outcome. Furthermore, this case suggests that a colouterine fistula caused by complicated diverticulitis can be managed with Hartmann's procedure without hysterectomy. Conclusion: Clinicians should consider complicated diverticulitis as a potential cause of TOA, even in the absence of radiologic signs. Multidisciplinary collaboration and individualized surgical management are essential for optimal outcomes in these rare and complex cases.