An unusual case of anti-MOG CNS demyelination with concomitant mild anti-NMDAR encephalitis.

We report the case of a patient who presented with progressive unsteadiness and narcoleptic attacks followed by behavioral change and psychosis, without visual disturbances or seizures. MRI revealed multiple areas of fluid attenuation inversion recovery (FLAIR) high-intensity lesions involving the cerebellum, brainstem, thalamus and third ventricular peri-ependymal region consistent with demyelination. Both the serum myelin oligodendrocyte glycoprotein-antibodies (MOG-Abs) and cerebral spinal fluid (CSF) anti-N-methyl-d-as-partate receptor (NMDAR) antibodies were positive using transfected cell based assays. The patient presented simultaneously with symptoms of MOG antibody disease and anti-NMDAR encephalitis, an unusual clinical scenario, indicating the co-existence of the two disorders.