A Case of Longitudinal Extensive Transversal Myelitis in Patient With Neuromyelitis Optica Spectrum Disorder and Systemic Lupus Erythematosus.

Neuromyelitis optica spectrum disorder (NMOSD) is a rare autoimmune, demyelinating disorder of the central nervous system. Clinical manifestations include optic neuritis, longitudinally extensive transverse myelitis (LETM) involving three or more vertebral segments, and, in most cases, seropositivity for anti-aquaporin-4 antibodies (AQP4-IgG). Although longitudinally extensive transverse myelitis (LETM) is a hallmark feature of NMOSD, it is not pathognomonic and may occur in a variety of infectious, metabolic, neoplastic, and autoimmune conditions, including systemic lupus erythematosus (SLE). Here we report the case of a female patient who presented with severe tetraparesis, secondary to transverse myelitis. Serological evaluation revealed positivity for anti-AQP4 antibodies, anti-dsDNA antibodies, and ENA antibodies, leading to the simultaneous diagnosis of NMOSD and SLE. Nevertheless, it remained uncertain whether the transverse myelitis represented a manifestation of NMOSD or neurological involvement of SLE.