Rituximab for tumefactive demyelination refractory to corticosteroids and plasma exchange

A 38-year-old woman with no significant past medical history presented with a generalised tonic–clonic seizure. The patient was afebrile and general physical and neurological examinations were normal. MRI of the brain revealed an irregular mass in the right temporal lobe with T2-weighted and fluid-attenuated inversion recovery (FLAIR) signal hyperintensity and heterogeneous enhancement after the administration of gadolinium (figure 1A–D). Laboratory investigations included normal blood count, liver enzymes, serum creatinine, angiotensin converting enzyme and erythrocyte sedimentation rate (ESR). Serum serologies for lyme, syphilis, viral hepatitis, brucella and HIV were negative. Tests for antinuclear antibodies, extractable nuclear antigens, rheumatoid factor and antinuclear cytoplasmic antibodies were negative. A chest and abdominal CT was normal. The patient was treated with levetiracetam and a biopsy …