Primary Cutaneous Cryptococcosis in a Patient on Fingolimod: A Case Report

Primary cutaneous cryptococcosis is an uncommon condition. Patients with immunosuppression and those of older age are more susceptible to infection, warranting investigations into underlying systemic disease. We report the case of a 49-year-old male with multiple sclerosis in remission on fingolimod who presented with a non-healing skin lesion on his upper thigh for a duration of two years. Skin biopsy showed dermal parasitized histiocytes, and serum antigens for histoplasmosis and Cryptococcus were negative. Further investigation with polymerase chain reaction (PCR) demonstrated cutaneous cryptococcal infection, with no associated systemic signs or symptoms. This case report highlights an uncommon presentation of cutaneous cryptococcosis on an unexposed skin surface with successful and rapid improvement following fluconazole therapy without fingolimod discontinuation.