Key predictors of poor functional outcome included ‘altered consciousness’ (OR 7.08, p < 0.001), higher ‘mRS at admission’ (OR 0.03–0.07 across categories, p < 0.001), ‘focal/generalized EEG slowing’ (OR 9.97, p < 0.001), ‘epileptiform EEG activity’ (OR 17.49, p < 0.001), ‘MRI: myelitis’ (OR 16.44, p = 0.004), and ‘intrathecal IgM synthesis’ (OR 8.93, p = 0.018). The gene discussed is CD40LG; the disease is myelitis.