Pneumoperitoneum in a patient with lymphangiomyomatosis.

A 32-year-old Japanese housewife with a 2-year history of retroperitoneal and pulmonary lymphangiomyomatosis had a sudden onset of severe abdominal pain. Chest X-ray and plain abdominal films showed free air under the diaphragm and a small pneumothorax in the left lower pleural space. Emergency laparotomy revealed no perforated viscera, but there was a rupture in the mid-portion of the left diaphragm. It appears that increasing pressure in the left pneumothorax burst the left diaphragm leading to pneumoperitoneum.