Chronic pulmonary coccidioidomycosis: computed tomographic and pathologic findings in 18 patients.

OBJECTIVE: To review the computed tomographic (CT) findings in pathologically proven chronic pulmonary coccidioidomycosis.

PATIENTS AND METHOD: The study included 19 pulmonary lesions caused by mycologically and pathologically proven chronic coccidioidomycosis in 18 immunocompetent patients (aged 22 to 75 years, mean 57 years) who had a chest CT scan. Thirteen patients were Canadians who had travelled to an endemic area, and 5 were inhabitants of an endemic area in southern California and Arizona. The CT findings were assessed to determine the type, size, margin, internal architecture and location of parenchymal abnormalities.

RESULTS: The CT findings included solitary nodules of 1.0 to 2.0 cm (mean 1.7 cm) in diameter in 17 patients, a focal area of ground-glass attenuation in 1 patient, and focal consolidation in 1 patient. Ten of the nodules had homogeneous attenuation on CT, 2 had central areas of low attenuation, 2 showed cavitation, 2 had foci of calcifications and 1 had bubble lucency. The nodules were located peripherally (in 14 patients) and centrally (in 3 patients). The predominant histologic finding in these nodules was a necrotizing granuloma. Three nodules were surrounded by halos of ground-glass attenuation, which were shown on histologic examination to represent granulomatous inflammation (in 2 cases) and pulmonary hemorrhage due to a pulmonary artery-bronchial fistula (in 1 case). Two nodules had adjacent consolidation, which was due to granulomatous inflammation surrounding a necrotizing granuloma.

CONCLUSION: Necrotizing granulomas in chronic coccidioidomycosis appear as a well-defined nodule on CT, while granulomatous inflammation may appear as areas of ground-glass attenuation or consolidation.