A case of chemical peritonitis and pleuritis caused by spontaneous rupture of a benign cystic ovarian teratoma that improved without surgical intervention.

Rupture of a benign cystic ovarian teratoma may result in severe chemical granulomatous peritonitis, a condition mimicking peritonitis carcinomatosa, with patients complaining of common abdominal symptoms. As the precipitating cause of rupture is often indeterminate and the rupture itself is hard to recognize, it is difficult to differentiate from peritonitis of other etiologies, such as gastrointestinal malignancy. We report the case of a 72-year-old female who presented with recurrent pyrexia and abdominal distension.