Infected intraperitoneal collection mimicking pneumoperitoneum.

Acute abdomen is an emergent condition that requires immediate evaluation and prompt treatment. Pneumoperitoneum is defined as the presence of air or gas in the peritoneal cavity. There are various potential causes of pneumoperitoneum, as well as conditions that can mimic or pseudo pneumoperitoneum. We encountered a case of a 26-year-old woman who had a history of postexploratory laparotomy, left ovarian cystectomy, left ovarian reconstruction, right salpingooophorectomy, and infracolic omentectomy for bilateral mucinous cystadenoma and mature cystic teratoma. On the eighth day following her operation, she developed progressive abdominal distension.