Trachipleistophora hominis infection in the myocardium and skeletal muscle of a patient with AIDS

Objectives. To review the literature relevant to microsporidial infection of muscle and to describe a case of human microsporidial infection involving both skeletal and cardiac muscle. Methods. Samples from an AIDS patient with myositis have been examined by light and electron microscopy. Results. We describe the findings at autopsy of a 47 year old Australian male with late stage AIDS, who had skeletal and cardiac muscle involvement with the microsporidian Trachipleistophora hominis. This is the third definitively identified case of human T. hominis infection and the first to describe infection of the myocardium. Conclusions. Microsporidial infection of muscle is rare in humans, but more work is needed to elucidate both the organisms and routes of transmission of this group of parasitic protozoa.