A case of acute colonic pseudo-obstruction, sigmoid volvulus, and massive pneumoperitoneum in a young female patient.

INTRODUCTION AND IMPORTANCE: Acute colonic pseudo-obstruction (ACPO) is an uncommon phenomenon that is especially rare in young patients and can result in bowl ischemia and perforation if left untreated. Furthermore, pneumoperitoneum is almost always a concerning imaging finding and in the context of recent colonic resection may be a sign of anastomotic leakage.

CASE PRESENTATION: We describe a case of a young female patient with postpartum ACPO who subsequently underwent a hemicolectomy with colorectal anastomosis. The patient's hospital course was complicated by massive postoperative pneumoperitoneum that resulted in resection of the anastomosis and creation of an end colostomy. However, despite this measure, there was recurrent pneumoperitoneum on cross-sectional imaging 36 h later. This was treated non-operatively and the remainder of their hospital course was uneventful.

CLINICAL DISCUSSION: A potential etiology for ACPO during pregnancy may be due to compression of parasympathetic plexus nerves by the gravid uterus. Idiopathic pneumoperitoneum has been documented on a number of occasions, though this is generally in older patients. It can present with signs of peritonitis or can be asymptomatic. Simultaneous pneumothorax and pneumoperitoneum is rare and may be due to the transmission of air from the peritoneum to the mediastinum and thorax. The pneumoperitoneum itself may be due the air leakage through the significantly distended colon into the peritoneum.

CONCLUSION: The combination of ACPO following pregnancy and associated pneumothorax, pneumomediastinum, and recurrent pneumoperitoneum suggest a communicating defect between the thoracic, mediastinal, and peritoneal cavities. Furthermore, the possibility of underlying colonic dysmotility should be considered prior to the restoration of large bowel continuity.