Among 28 relapsing patients with negative AQP4-Ab, 19 presented ON and TM, 1 had ON + TM + area postrema syndrome, 3 patients experienced TM and area postrema syndrome, 1 patient presented TM + area postrema syndrome + acute brainstem syndrome, and 4 patients experienced ON and area postrema syndrome during follow-up. Here, AQP4 is linked to Down syndrome.