Spontaneous Perforation of Ascending Colon Presenting as Retroperitoneal Abscess: A Case Report

Abstract

Perforation of the colon is frequently encountered in surgical emergencies and requires urgent intervention. Free colonic perforations are diagnosed early due to the development of signs of peritoneal irritation. However, perforation of the posterior wall of the colon into the retro-peritoneal space poses a diagnostic challenge because of the absence of signs of peritoneal irritation and its atypical clinical presentation. The authors reported an unusual case of 42 years old female patient with idiopathic perforation of the posterior wall of the ascending colon that presented as a large retroperitoneal abscess. The abscess was diagnosed based on clinical and Computed Tomography (CT) findings, and the patient underwent incision and drainage of the abscess through a flank incision. There was initial improvement in the patient’s general condition, but on the fourth day, there was faecal discharge through the wound, indicating colonic perforation. The patient was immediately taken for an emergency laparotomy. Intraoperatively, the peritoneal cavity was found to be clean; however, upon mobilisation of the ascending colon, two large perforations on its posterior wall were found with faecal soiling of the retroperitoneal tissues. Right hemicolectomy with end ileostomy and closure of the transverse colonic end were performed. Histopathology revealed the absence of any definite pathology, and a diagnosis of spontaneous perforation was made. This unusual case highlights that this rare possibility should be considered as a differential diagnosis of a retroperitoneal abscess to enable early intervention, which is likely to save the patient.