Studies on the fungal flora in the lung of human necropsy cases. A critical survey in connection with the pathogenesis of opportunistic fungus infections.

An ecological study was carried out on the fungal flora in the human lung of 159 autopsy cases. Fungi were isolated from 129 cases (81.1%). Filamentous fungi consisting of 918 strains were isolated from 113 cases, and the dominant genera were Aspergillus and Penicillium. Yeasts were isolated from 58 cases, and the dominant genus appeared to be Candida. With morbid anatomical study, the incidence of the fungus isolation was examined from various points of view. It was concluded that even a healthy respiratory parenchyma of the human lung cannot be assumed as aseptic. However, only a few numbers of a few genera of air-born fungi were isolated. Special stress was laid on the exposure of the respiratory parenchyma of the human lung to air-born fungi in connection with the pathogenesis of opportunistic fungus infections.