Abstract

The clinical, radiographic, and laboratory findings have been reviewed in a series of 22 patients with definite and 10 with probable allergic aspergillosis. Episodes of segmental shadowing occurred most frequently in the upper lobes and tended to recur in the same segment. Radiologically visible mucoid impaction of a large bronchus was demonstrated in eight cases, and saccular bronchiectasis in six cases, in the affected segments. Two patients have recovered, eight continued to experience episodic symptoms and shadows for up to 13 years, and 11 are on steroid therapy with relief of airways obstruction and prevention of further lung shadows. Four, together with five others who probably represent a late stage of the disease, have upper lobe contraction. One patient developed aspergillomas and one died with invasive aspergillosis. Sputum has remained positive in all except one patient. Precipitins were present in all cases. They varied widely in strength and appeared to be more closely related to the amount of antigenic exposure than to the severity of the allergic manifestations. Allergy to Aspergillus fumigatus probably plays a dominant role in the symptomatology of those with asthma of late onset; evidence of underlying atopic diathesis and of increased spore exposure could usually be adduced in these patients. A quantitative interaction of atopic diathesis and contact with a growing source of fungal antigens will result in a locally florid bronchial reaction, with plugging and subsequent dilatation. The peripheral shadows are consistent with areas of collapse distal to bronchial occlusion. The frequency and distribution of mucoid impaction found in this series suggest that allergic aspergillosis may be a major cause of this uncommon syndrome, which could represent an exaggerated form of bronchial plugging.