RESUMO
Radiographic findings of free air in the peritoneal cavity secondary to perforation of a acutely inflamed appendix are extremely rare. It accounts for about 0-7% of all patients with pneumoperitoneum. We report on a 58-years-old Brazilian Amazon woman presenting a 1- week history of abdominal pain, tenderness and distension associated with asthenia and without passage of stool or gas. Abdominal percussion revealed a tympanic sound located on the right hypocondrium. Plain chest radiography revealed a large amount of free air beneath the right leaf of the diaphram. The patient was taken immediately to the operation room and, during surgery, a gangrenous appendix with an apex perforation was verified. Appendectomy was performed as routinely. The patient evolved with pneumonia and septic shock that responded well to intravenous antibiotics and vasoactive drugs. She was discharged to home on the twenty-first post-operative day in good clinical conditions. This case highlights that perforated acute appendicitis is rarely associated with pneumoperitoneum, but it must be considered in the differential diagnosis of patients presenting right abdominal pain and free intraperitoneal air.