Lesson of the month 1: Pericardial mass and cardiac tamponade associated with Mycoplasma pneumoniae.

Mycoplasma pneumoniae primarily causes respiratory tract infections. Extrapulmonary manifestations are seen in 20-25% of cases. Cardiac involvement is rarely reported. We present a unique case of a pericardial mass and cardiac tamponade associated with a Mycoplasma pneumoniae pneumonia. This required emergency pericardial fenestration. The patient improved dramatically postoperatively on antibiotics and there was no recurrence of the pericardial effusion on follow up. This case highlights the often forgotten invasive properties of a common respiratory tract pathogen and emphasises the need to consider this easily treatable entity in the differential diagnosis of idiopathic pericardial effusions.