Massive Pneumoperitoneum Presenting as an Incidental Finding.

Pneumoperitoneum is often associated with surgical complications or intra-abdominal sepsis. While commonly deemed a surgical emergency, pneumoperitoneum in a minority of cases does not involve a viscus perforation or require urgent surgical management; these cases of "spontaneous pneumoperitoneum" can stem from a variety of etiologies. We report a case of a 72-year-old African American male with a history of metastatic pancreatic adenocarcinoma who presented with new-onset abdominal distention and an incidentally discovered massive pneumoperitoneum with no clear source of perforation on surveillance imaging. His exam was non-peritonitic, so no surgical intervention was recommended. He was treated with bowel rest, intravenous antibiotics, and hydration. He had a relatively benign clinical course with preserved gastrointestinal function and had complete resolution of his pneumoperitoneum on imaging two months after discharge. This case highlights the importance of considering non-surgical causes of pneumoperitoneum, as well as conservative management, when approaching patients with otherwise benign abdominal exams.