Tumefactive multiple sclerosis lesions under fingolimod treatment

Fingolimod is an oral sphingosine 1-phosphate receptor modulator that prevents recirculation of lymphocyte subsets from lymph nodes. It decreases the number of relapses, slows the progression of disability, and improves MRI endpoints in patients with relapsing-remitting multiple sclerosis (RRMS).1 Infrequent but specific side effects are bradycardia, leukopenia, and macular edema. ### Case report. In November 2010, a 23-year-old woman with RRMS since September 2007 started fingolimod 0.5 mg per day in the setting of the open-label FTY720D2316 trial. Interferon-β treatment was initiated in 2008, but discontinued mid-2010 because of side effects. Her disease course was relatively mild with low frequency and complete recovery of relapses. In March 2011, she presented with a left-sided hemiparesis, headache, and nausea that had gradually developed over 2 weeks. Because she had no clinical signs of infection, an exacerbation of multiple sclerosis (MS) was considered initially and she was admitted for IV methylprednisolone …