Pathogenesis of paracoccidioidomycosis: a model based on the study of 46 patients.

Forty-six Paracoccidioidomycosis patients were studied with emphasis on lung pathology. It was found that the greatest clinical involvement of the reticuloendothelial system occurred in younger individuals. On the other hand, the frequency of tegumentary lesions was low in young patients and increased with age. Lung involvement was nearly always demonstrated when searched for and showed no relationship to the patient's age. In the young patients the disease was acute while in the older individuals its course was chronic. The findings from this study permitted formulation of a model for the pathogenesis of paracoccidioidomycosis in which the respiratory tract is accepted as the primary site of infection. Based on this model, a classification of the various forms of the entity is proposed.