FATAL CEREBRAL MYCOSES CAUSED BY THE ASCOMYCETE CHAETOMIUM-STRUMARIUM

Three cases of fatal cerebral mycosis in males with prior histories of intravenous drug use from the United States and Australia are reporte d. Infection in each case was limited to brain abscess; no other sites of infection were observed. The fungus seen by histopathology and iso lated from the brain tissue in each case was identified as Chaetomium strumarium. This is the first report of human infection by this specie s, and C. strumarium is the second species of Chaetomium known to caus e primary brain infection. Chaetomium strumarium is unusual among memb ers of the genus Chaetomium in forming ascocarps covered with pale, th in-walled, flexuous hairs, a feature leading to its original placement in the genus Achaetomium. Presence of pinkish exudate droplets and/or crystals associated with hyphae or ascocarps, sometimes accompanied b y a pinkish diffusible pigment; good growth at 42 degrees C; and produ ction of small conidia further distinguish this species. The brain abs cess isolates were compared,vith isolates from prior cases of cerebral infection which had been identified as either Chaetomium atrobrunneum or Chaetomium globosum. With reidentification of one isolate original ly identified as C. globosum to C. atrobrunneum, only C. strumarium an d C. atrobrunneum have been confirmed to cause infection involving the brain.