Autoimmune Myelitis and Myocarditis in a Patient With Anti-Aquaporin-4, Antinuclear, and Antiphospholipid Autoantibodies: The Neuromyelitis Optica-Systemic Lupus Erythematosus (NMO-SLE) Overlap Syndrome

The coexistence of two or more autoimmune diseases is well-known, e.g., a person can have neuromyelitis optica (NMO) and systemic lupus erythematosus (SLE) at the same time. We report a case of NMO-SLE overlap syndrome with myelitis and myocarditis as the initial manifestations. The patient, a 64-year-old man, presented with a 15-day history of ascending sensory loss and a 10-day history of exertional dyspnea. Magnetic resonance imaging (MRI) revealed longitudinally extensive transverse myelitis (LETM) from C7 to T6. Serology showed a high anti-aquaporin-4 antibody level. We diagnosed NMO based on these findings. Echocardiography showed a hypokinetic left ventricle with a severely reduced ejection fraction. Cardiac MRI demonstrated delayed gadolinium enhancement in the myocardium consistent with active inflammation. Because the cardiac findings could not be explained on the basis of NMO, we started searching for another autoimmune disease. Serology came back positive for a variety of autoantibodies, including antinuclear, anti-dsDNA, anti-chromatin, anti-cardiolipin, anti-β2-glycoprotein-1, and lupus anticoagulant. These findings, along with leukopenia and low serum complement C4, prompted us to diagnose SLE, in addition to NMO. He was initially treated with plasmapheresis and methylprednisolone. Maintenance therapy consisted of rituximab, hydroxychloroquine, and aspirin. One year later, he only complained of mild paresthesia in the feet. Patients with NMO should always be screened for SLE especially if they have signs and symptoms that cannot be accounted for by NMO alone, e.g., our patient had myocarditis. Conversely, patients with SLE and evidence of transverse myelitis should be screened for anti-AQP4 antibodies.