North American blastomycosis

Abstract

In 35 cases of pulmonary blastomycosis, the roentgenologic features were as follows: consolidation 26%, mass 31%, intermediate-sized nodules 6%, miliary pattern 11%, solitary cavity 9%, fibrotic and cavitary changes 6%, interstitial pattern 6%, diffuse alveolar involvement 3%, and mixed alveolar and interstitial infiltrate 3%. All symptomatic cases of consolidation were acute (symptoms for less than 1 month), and most were in young patients (mean age, 34 years). Consolidation constituted 58% of the acute cases in this series. Two of the nine cases of consolidation were asymptomatic epidemic cases detected by screening. A pulmonary mass was the most common initial manifestation in this series; it tended to occur in patients with chronic symptoms (more than 1 month). The mass was considered suggestive enough of bronchogenic carcinoma to necessitate resection in 55% of cases. The miliary form of pulmonary blastomycosis occurred in older patients with disseminated disease. Fibrotic and cavitary disease was chronic in nature. The presence of intermediate-sized nodules elsewhere in the lung proved to be a helpful diagnostic finding in several patients with consolidation, mass, or cavitary disease. Hilar adenopathy, postinfectious calcification, chest wall invasion, and pleural effusion occurred infrequently or not at all in this series.