Pneumocystis carinii in Human Lungs at Autopsy

Abstract

To get some information about the prevalence of Pneumocystis carinii in the Danish population we have examined autopsy lung biopsies from patients at 2 large hospitals in Copenhagen, Rigshospitalet (RH) and Finseninstituttet (F), in a 5-year period from 1979 to 1984. Imprints made from the biopsies were stained with the toluidine blue O method and examined microscopically for pneumocysts. A total of 1762 patients were examined and pneumocysts found in 83 (4.7%); at RH 54 (4.9%) of 1106 patients and at F 29 (4.4%) of 656 patients. A possible influence of certain climatic factors on the prevalence of pneumocysts in humans was shown: low temperature, low vapour pressure and low relative humidity seem to be correlated with low prevalence of pneumocysts. The general use of trimethoprim-sulfamethoxazole in the hospitals may possibly influence the prevalence of pneumocysts: the amount requested in the period of the investigation is negatively correlated with the prevalence of pneumocysts.