By 2017, she achieved seronegativity and remained relapse-free until January 2023, a decade post-AHSCT (6 years post-seroreversion), when she presented with myelitis confirmed by magnetic resonance imaging (MRI), showing active longitudinal extensive transverse myelitis (LETM) at the C2 to C5 levels of the cervical spine (Figure 1) and seroconverted to positive (AQP4-IgG titer 1:100 000). This evidence concerns the gene AQP4 and myelitis.