Studies on Aspercillus Fumigatus Bronchopulmonary Aspercillosis

Abstract

In 262 chest patients at the City Hospital, Edinburgh, sputum < \ i \ v i samples were examined microscopically for as pe rgi 1lus-type mycelium and sputum eosinophilia and cultured for aspergillus. Prick-skin and intradermal hypersensitivity tests to A.furnigatuo antigens were carried out and the production of immediate and late reactions noted. A serum precipitin test to A.fusigatus antigens was performed, and precipitation reactions were observed after staining the medium in the agar gel double-diffusion test. Swabs from the upper respiratory tract were cultured for aopergillus. Of the 262 patients 31 were selected as regards a probable diagnosis of bronchopulmonary aspergillosis and 231 were unselected. Two types of growth of A.furaigatus in sputum cultures was observed* abundant growths considered significant and light growths not so considered. Contamination of culture plates with atmospheric A.fumigatus spores was a problem. There was a seasonal variation, with a winter peak, in the incidence of light growths of A.furaigatus from cultures of sputum and swabs and in the incidence of contaminant growths on culture plates. There was no association between isolation of A.fumigatus from swab cultures and abundant growths of A.furaigatus from sputum. Among unselected cases the incidence of significant growth of A.fusigatus from sputum was 10.8% and of other species of aspergillus 2.6%. The incidence of serum precipitating anti¬ bodies to A.funigatus antigens was 3.4% and of positive reactions in skin hypersensitivity tests to A.fumigatus antigens 16,5%. Significant growth of A.funigatus from sputum was associated with purulence of sputum and sputum eosinophilia. The intra¬ dermal test was considered superior to the prick-skin test in terms of the number of positive reactions obtained. The serum precipitin test appeared as the most reliable diagnostic index of bronchopulmonary aspergillosis, 22 cases were considered to have bronchopulmonary asper¬ gillosis and factors in their environment and symptomatology are discussed. The Incidence of known bronchopulmonary aspergillosis among chest patients at the hospital was 1.0%, mid among unselect¬ ed cases intensively studied 3»9%* A method for obtaining constant end-points in assessing the minimal inhibitory concentration of pimaricin for A.funigatus strains is described.