Infection of Pneumocystis Carinii and Cytomegalovirus in Autopsied Lungs

Autopsied lungs at our department during 1965 to 1967 (group I), and during 1978 to 1979 (group II) were examined for pneumocystis carinii (Pc) and cytomegalovirus (CMV) infection. In addition, autopsied lungs from patients who died of malignant tumor of hematopoietic organs during 1972 to 1982 (group III) were also selected to observe Pc and CMV infection. Although Pc infection was not detected in group I (118 cases), it was recognized on 8 out of 123 cases of group II. This difference was significant at a P value of less than 0.05. The underlying diseases associated with Pc infection included 7 malignant tumors and 1 SLE. Pc infection was demonstrated in 20 out of 102 cases of group III. Microscopically, there were variable number of Pc, eosinophilic materials showing foamy appearance, and hyalin-like materials in the alveolar spaces. Pc was stained black with Gomori's methenamine silver (Grocott stain) and blue with toluidine blue-O. Although CMV infection was not demonstrated in group I, it was recognized on 5 in group II and 11 in group III. The increased incidence of Pc and CMV infection in group II and III is probably caused by more aggressive therapy (anticancerous drugs, corticosteroids and antibiotics) for the underlying diseases.