Cryptococcal osteomyelitis of the skull

An otherwise healthy 65-year-old male from a rural area presented with a 1-month old non-tender scalp mass. He had a history of being stuck with a stone in the parietal region a year earlier but hadn't developed any complications. Needle aspiration of the mass revealed numerous yeast cells, which were confirmed to be Cryptoccus neoformans. This case describes a rare presentation of C. neoformans infection in a human immunodeficiency virus (HIV)-negative patient. Moreover, while osteomyelitis due to Cryptococcus is generally preceded by fungemia, in the present case it was caused by direct inoculation of the etiologic agent. We review 11 similar cases published since 1983 in which most of the patients developed an insidious mass in their scalps with osteolytic lesions as seen on X-ray and all were HIV-negative. Nine of the eleven patients in these cases had good recovery after surgical debridement and treatment with amphotericin B, flucytocise and/or fluconazole. The remaining two patients died during hospitalization. Cryptococcal osteomyelitis should be part of a differential diagnosis when confronted with an insidious growing mass or abscess of unclear origin in the scalp.