Is It Lupus? Is It Neuromyelitis Optica Spectrum Disorder (NMOSD)?—Why Not Both?

Multiple sclerosis (MS) and neuromyelitis optica spectrum disorders (NMOSD) are among the commonly considered differential diagnoses in patients with inflammatory central nervous system (CNS)-diseases. Formerly diagnosed competing autoimmune diseases might impair diagnostics and treatment. Here, we report on a 41-year-old woman admitted to our hospital with primary manifestation of NMOSD (paresthesia, paralysis of the lower extremities, and urinary incontinence) while undergoing treatment for a diagnosed systemic lupus erythematosus (SLE) with hydroxychloroquine. CNS manifestation of the disease was considered. Magnetic resonance imaging (MRI) of the cranium and spinal cord showed multiple supratentorial lesions of the white matter and massive intramedullary lesions with contrast enhancement. Cerebrospinal fluid (CSF) showed pleocytosis (20/µL), positive antinuclear antibodies (ANA), antiphospholipid antibodies, and SSA/Ro antibodies, while formerly positive dsDNA antibodies were negative. Further diagnostics revealed a 1:10,240 serum titer of Aquaporine-4 antibodies. The patient received intravenous methylprednisolone for three days (2 g per day), which led to an escalation to plasmapheresis and to an improved EDSS from 8.0 to 4.0. Because of the comorbidity, a combined relapse prophylaxis with satralizumab and mycophenolate mofetil was established. Rehabilitation and continued treatment improved EDSS to 1.0 with no impairment of mobilization. Although formerly diagnosed SLE could have explained the symptoms, it is important to reconsider competitive diseases in order to establish adequate immunotherapy.