Necrotizing fungal osteomyelitis and fingolimod, 4 years after treatment with fingolimod.

Fingolimod has been the first approved oral medication in MS for its relapsing remitting type. It is a non-selective sphingosine1-phosphate (S1P) receptor modulator on lymphocytes. Engagement of this receptor blocks the T cells and B cells migration from the lymph nodes into the inflamed central nervous system (CNS) via bloodstream. In spite of this known immunomodulatory mechanism, there are some reports about serious infection following the initiation of fingolimod therapy like herpes types or infections associated to the immunosuppressed situation (cryptococcal meningitis, primary cutaneous cryptococcosis and visceral leishmaniasis). To the best of our knowledge, in contrary to many reports about opportunistic or serious infections with fingolimod, there has been no report on fungal osteomyelitis associated to fingolimod until now. Here, we aimed to describe a woman who developed necrotizing fungal osteomyelitis four years after starting fingolimod, as a disease modifying drug for MS.