# A Case of Suspected Colocutaneous Fistula Within an Incisional Hernia Secondary to Sigmoid Diverticulitis in an Elderly Patient With Prior History of Cystectomy and Ileal Conduit Formation

## TL;DR

An elderly patient with a history of cystectomy developed a rare fistula between the colon and abdominal wall due to diverticulitis, successfully managed with antibiotics and drainage.

## Contribution

This case report highlights the rare occurrence of a colocutaneous fistula in a patient with altered pelvic anatomy due to prior surgery.

## Key findings

- A colocutaneous fistula was suspected via imaging in a patient with a history of cystectomy and ileal conduit formation.
- Treatment with antibiotics and drainage led to clinical improvement and resolution of sepsis.
- The case emphasizes the need for cross-sectional imaging in atypical diverticulitis presentations.

## Abstract

Diverticulitis is a common colonic pathology, but fistulous communication with the anterior abdominal wall is rare. We report a case of a suprapubic abscess with a radiologically suspected colocutaneous fistula arising from sigmoid diverticulitis in an 87-year-old man with prior cystectomy and ileal conduit formation. Laboratory investigations demonstrated significant inflammation, and contrast-enhanced computed tomography revealed a thick-walled suprapubic collection with a defined tract extending to an inflamed segment of sigmoid colon, consistent with a colocutaneous fistula. Management involved intravenous broad-spectrum antibiotics and ultrasound-guided percutaneous drainage, resulting in clinical improvement and resolution of sepsis. The patient was discharged with a plan for outpatient follow-up, and consideration of elective sigmoid resection should the fistula persist. This case highlights the importance of recognising atypical presentations of diverticulitis in patients with altered pelvic anatomy and underscores the role of cross-sectional imaging in diagnosis and guiding management.