Fine-needle aspiration biopsy of pulmonary coccidiodomycosis. Spectrum of cytologic findings in 73 patients

Abstract

Coccidioides immitis, the causal agent of coccidiodomycosis, is endemic in the arid desert regions of Mexico and the southwestern United States. Individuals may acquire the disease through the inhalation of conidia. The majority of infected patients are asymptomatic or exhibit flu-like symptoms. Two percent of infected individuals ultimately demonstrate a solitary pulmonary nodule that may be radiographically indistinguishable from neoplasms or other infectious lesions. This report describes the spectrum of cytologic findings in 73 patients who were diagnosed with pulmonary coccidiodomycosis by fine-needle aspiration (FNA) biopsy. The patients ranged in age from 30 to 92 years. Ten had a previous history of malignancy. The smears were characterized by a large amount of granular, eosinophilic debris with a paucity of acute or chronic inflammation. Granulomatous inflammation was present in only three cases. The diagnosis was confirmed by the cytologic observation of C. immitis spherules that ranged in size from approximately 20 to 200 microns. Many of these spherules had a crushed or fractured appearance, and occasional calcified forms were seen. Endospores were observed in intact spherules and were rarely observed outside these spherules. Mycelial elements occasionally were present. C. immitis were cultured in 9 of 44 cases in which fungal cultures were obtained. The cytologic differential diagnosis, which includes contaminant, other infectious diseases and malignancies, is discussed.