Cardiac thrombus associated with Mycoplasma pneumoniae infection.

Thrombosis is a very rare complication of Mycoplasma pneumoniae infection. We report the case of a previously healthy nine-year-old boy with cardiac thrombus in the right ventricle associated with M. pneumoniae pneumonia. This cardiac thrombus was detected eight days after the onset of respiratory symptoms. The mechanism underlying thrombosis may be related to autoimmune modulations and was attributable to the production of transient antiphospholipid antibodies.