Pulmonary coccidioidomycosis found in healthy Japanese individuals

Coccidioidomycosis is endemic in the south-western USA. This study described the clinicopathological features of pulmonary coccidioidomycosis found in otherwise healthy Japanese individuals.

Four male patients with pulmonary coccidioidomycosis were assessed by clinical examination, serology, PCR assay, high-resolution computed tomography and histopathological findings.

All patients had returned to Japan from the USA and all presented with an abnormal CXR during routine assessment; two of the patients were symptomatic. High-resolution computed tomography showed a well-defined homogenous nodule or mass adjacent to the pleura. All patients underwent surgical wedge resection. Histopathological examination revealed encapsulated caseating epithelioid cell granulomas containing spherules and endospores. Serum IgG antibody was negative in all patients, but PCR assay using DNA from resected specimens demonstrated the presence of coccidioides-specific DNA.

Pulmonary coccidioidomycosis is very rare in Japan, but it can be found incidentally during routine evaluation. The main high-resolution computed tomography findings are a well-defined homogenous nodule adjacent to the pleura, reflecting the histological feature of encapsulated granulomas. PCR assay is useful for confirming the presence of coccidioides.