57. Primary cutaneous cryptococcosis – a cytological and histological diagnosis

We report a case of a primary cutaneous cryptococcosis (PCC) in an immunocompetent man, diagnosed by fine-needle aspiration (FNA) and histological examination of the excised cyptococcoma, confirmed by special stains and culture study. A previously healthy 23-year-old man with no history of immunosupression or local trauma, presented with a 140 mm solitary, painful subcutaneous mass in the thigh. CT showed a well circumscribed low density mass in the subcutaneous tissue abutting but not infiltrating the deep muscles. FNA smears revealed pure yeast forms of cryptococcus surrounded by clear halos. Macroscopically the excised lesion was a circumscribed subcutaneous mass with a prominent myxoid, gelatinous appearance. Histological examination showed numerous yeast forms of cryptococcus with minimal inflammation. The organisms were also demonstrated by special stains and electron microscopy. Cryptococcus neoformans was confirmed subsequently by microbiological studies. There was no evidence of disseminated cryptococcosis. PCC, a rare distinct clinical entity, can occur in immunocompetent hosts, and carries a much better prognosis than secondary skin involvement by disseminated cryptococcosis. PCC may rarely present as a solitary mass with prominent gelatinous contents mimicking myxoma. This case also emphasises the role of FNA as a useful modality in the early diagnosis of cutaneous cryptococcosis, especially in clinically unsuspected cases.