Concurrent Primary Cutaneous Cryptococcosis and Bowen's Disease in a Patient With Multiple Sclerosis on Fingolimod: A Rare Case Report and Review of Literature.

Fingolimod is an oral disease-modifying treatment used for the relapsing-remitting forms of multiple sclerosis, which may render patients susceptible to opportunistic infections and lead to an increased risk of skin cancer. We report a 56-year-old woman with multiple sclerosis in remission on fingolimod treatment for five years presenting with the following skin lesions. Our patient presented with a non-healing ulcerated erythematous lesion on the left lower abdomen for six months and a crusted erythematous plaque on the forehead that had not healed for one year. Skin biopsy from the abdominal lesion showed fungal spores extending from the papillary dermis to the deep dermis, mostly in histiocytes and periodic acid-Schiff (PAS) staining revealed structures consistent with Cryptococcus. A moderate Cryptococcus neoformans infection was confirmed by culture. There were no systemic symptoms suggestive of secondary cutaneous cryptococcosis. In addition, a punch biopsy from the forehead showed findings compatible with Bowen's disease. Fingolimod was discontinued and the lesion on the left lower abdomen resolved with oral fluconazole therapy. Complete surgical excision with negative margin was performed for Bowen's disease. We present the first reported case of concurrent primary cutaneous cryptococcosis and Bowen's disease in the same patient with multiple sclerosis on fingolimod in the literature.