Complement inhibition: a therapeutic turning point in the treatment of recurrent myelitis in a patient with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) and neuromyelitis optica spectrum disorder (NMOSD) are autoimmune diseases that have been reported to coexist. We describe the case of a 61-year-old woman with long-standing SLE and Sjögren’s disease who developed recurrent longitudinally extensive transverse myelitis associated with concomitant NMOSD. Despite treatment with glucocorticoids, plasma exchange, and rituximab, she experienced multiple neurological relapses, with persistent positivity of anti-aquaporin-4 antibodies and magnetic resonance imaging findings consistent with NMOSD, while SLE remained clinically inactive. Therefore, we initiated treatment with an anti-C5 monoclonal antibody for relapse prevention. To our knowledge, this is the first reported case of a patient with coexisting SLE and NMOSD treated with an anti-C5 monoclonal antibody, remaining relapse-free throughout a 22-month follow-up period.