Azza Mahmoud

Neuropathic pain is a common, well-known and often difficult-to-treat symptom in neuromyelitis optica spectrum disorder (NMOSD) and is usually related to spinal cord lesions. However, non-neurological pain can coexist, posing diagnostic difficulties and delaying treatments. We describe the clinical course and diagnostic workup of a young woman with relapsing myelitis related to Aquaporin-4 (AQP4) IgG positive NMOSD who presented repeatedly to the neurology clinic with persistent pain affecting initially lower limbs and then upper limbs despite apparently stable neurological disease. Joint MRI demonstrated multifocal avascular osteonecrosis involving both femoral and humeral heads, distal humerus and knees. She underwent bilateral total hip replacement; other joints were managed conservatively. Avascular necrosis due to corticosteroid use can cause unexplained persistent pain and should be considered as a differential diagnosis not only in NMOSD but any condition requiring corticosteroids. Early diagnosis can ensure timely and appropriate management, relieving pain and minimising complications.

Background Neuromyelitis optica spectrum disorder (NMOSD) is a rare relapsing autoimmune disease of the central nervous system (CNS). Management during pregnancy is challenging due to limited safety data for disease-modifying therapies. Case presentation We report a case of a 41-year-old woman with aquaporin-4 (AQP4) IgG positive NMOSD who was switched from rituximab to ravulizumab during pregnancy. Ravulizumab was initiated shortly after conception and continued throughout pregnancy. Pregnancy was uneventful and she delivered a healthy term infant. At birth, umbilical cord blood testing revealed detectable ravulizumab levels and low C5 activity, confirming transplacental transfer of ravulizumab. The infant, now 4 months old, remains well. Conclusions This is the first reported case of ravulizumab use during pregnancy, with documentation of transplacental drug transfer and neonatal complement inhibition. Despite laboratory evidence of pharmacologic exposure, the neonate remained clinically well. These findings suggest that ravulizumab may be a viable treatment option for NMOSD during pregnancy when traditional agents are contraindicated or ineffective. However, further studies and longitudinal monitoring of exposed infants are essential to establish safety and clinical guidelines.