Multifocal small bowel gastrointestinal stromal tumor causing perforation peritonitis: A rare cause of acute abdomen

A female patient in late 40s presented with severe abdominal pain, distension and fever for a week. Ultrasound abdomen revealed ascites and a large indeterminate mass in the pelvis, but bowel loops were not dilated. Contrast-enhanced CT (CECT) abdomen revealed a large, exophytic, heterogeneously enhancing intraperitoneal mass, arising from a jejunal loop in the pelvis; showing fistulous communication with an adjacent small bowel loop. Multiple smaller enhancing rounded, serosal masses were also seen in the jejunum and ileum along with pneumoperitoneum, moderate ascites and peritoneal enhancement. A differential diagnosis of multifocal Gastrointestinal stromal tumor (GIST) or leiomyosarcoma was entertained on CECT. Exploratory laparotomy revealed one large and multiple small tumors along with and minute small bowel perforations; histopathology confirmed the diagnosis. Presentation of multiple small bowel GIST with perforation peritonitis on preoperative computed tomography (CT) has not been reported earlier.