In children, demyelinating ON can occur alone or in conjunction with MS, acute disseminated encephalomyelitis (ADEM), or as part of an autoantibody response to either AQP4 (NMOSD) or MOG (MOGAD).[19] Also, children younger than 10 years of age are more likely to present with bilateral ON and more likely to have a prodromal illness. The gene discussed is AQP4; the disease is myeloid sarcoma.