Unusual presentation of purulent pericarditis: diagnostic contribution of MRI.

Purulent bacterial pericarditis is an uncommon form of infectious pericarditis, occurring usually in immunocompromised patients. It may rarely present as a nodular or tumefactive lesion, and in such cases is liable to be confused with primary and metastatic tumors. We describe the imaging features and diagnostic contribution of CT and MRI in a 68-year-old woman with mass-like purulent pericarditis.