Basic and clinical aspects of pulmonary aspergillosis

Abstract

Reviewing the autopsy records of Japan, the number of pulmonary aspergillosis cases is increasing every year. Cases were classified into three types; allergic, fungus-ball and pneumonic type. The characteristics of disposition and disease process were comparatively analyzed. Recurrent pneumonia based on atopic disposition is particular to the allergic type, though scarcely found. Laboratory findings were the increase of serum IgE and the positive precipitin tests, indicative of allergic type I and III. It was pathohistologically featured by mucoid impaction with Aspergillus hyphae leading to the dilatation of rather proximal bronchi. A greater part of the fungus-ball type was a secondary infection to the foregoing diseases, mainly tuberculosis. Examining ten cases of the fungus-ball type, a partial fall of cellular immunity and the rise of humoral activity were found. A local factor may play an additional role in the pathogenesis. The characteristic process of primary type was massive pneumonia resolving into a large bullous dilatation followed by gradual diminution and finally the colonization of a mycelial mass occurred. Positive precipitin tests were indicative of the allergic type III and IV. Histological investigation revealed that many bronchi branching peripherally from the cavity were ulcerated by mycelia, and alveoli were also affected. A cavity with a fungus-ball was used to extend from the mid-lung to the pleura. Histological reaction was allergic type III and IV. The terminal stage of malignant disease or blood dyscrasia, where humoral and cellular resistance decreased, was often complicated with the pneumonic or disseminated type of pulmonary aspergillosis. Precipitin tests were negative and allergic or immune reaction was not detected histologically. The rise of immunoglobulin levels in the fungus-ball type was a prominent feature, contributory to clarify the pathogenesis.