Myelin Oligodendrocyte Glycoprotein Antibody-Associated Myelitis Presenting with Headache

Previously thought to be variants of multiple sclerosis, neuromyelitis optica spectrum disorders (NMOSDs) are now well recognized as distinct autoimmune CNS gliopathies.1 Diagnostic criteria from 2015 center around the occurrence of inflammatory lesions at one or more core clinical sites (including the optic nerves, spinal cord, and others), along with the presence of aquaporin-4 (AQP4)-IgG antibodies in serum, which target primarily astrocytes and initiate immune-mediated CNS damage.2 AQP4-seronegative patients need to meet more stringent clinical criteria to be classified as NMOSD. Approximately 1/4 to 1/3 of AQP4-seronegative patients are seropositive for myelin oligodendrocyte glycoprotein (MOG)-IgG antibodies, which find their antigen on oligodendrocytes.3 Overall, clinical manifestations of MOG antibody disease (MOGAD) may resemble AQP4-positive NMOSD, but MOGAD has emerged as an entity with its own distinguishing features.4 Patients with NMOSD and MOGAD commonly experience neuropathic pain and headache as part of their illness.5An observational study found that greater than 80% of 49 patients with NMOSD/MOGAD suffered from pain, including 5 of 12 MOGAD patients who experienced headache.5 These symptoms can also be the patient’s presenting concern, as we report here. Abbreviations: PCR = polymerase chain reaction; VZV = varicella zoster virus; HSV = herpes simplex virus; EV = enterovirus; Cytopath. = cytopathology; OCB = oligoclonal bands; TB = tuberculosis; ANA = anti-nuclear antibodies; ENA = extractable nuclear antigens; SPEP = serum protein electrophoresis; ACE = angiotensin-converting enzyme; MOG = myelin oligodendrocyte glycoprotein; AQP4 = aquaporin-4. In addition to aforementioned headache mechanisms, pain may relate to the disruption of ascending nociceptive and descending antinociceptive pathways, disturbed excitatory–inhibitory balance, and central sensitization.11 Further prospective study of symptom management in NMOSD and MOGAD is needed, since not all patients will have resolution of their symptoms with immunosuppression.