Acute disseminated encephalomyelitis

Acute disseminated encephalomyelitis (ADEM) is an immune mediated disease of the brain.It usually occurs following a viral infection but may appear following vaccination, bacterial or parasitic infection, or even appear spontaneously. As it involves autoimmune demyelination, it is similar to multiple sclerosis, and is considered part of the Multiple sclerosis borderlinediseases. The incidence rate is about 8 per 1,000,000 people per year. Although it occurs in all ages, most reported cases are in children and adolescents, with the average age around 5 to 8 years old. The mortality rate may be as high as 5%, full recovery is seen in 50 to 75% of cases, while up to 70 to 90% recover with some minor residual disability.The average time to recover is one to six months.ADEM produces multiple inflammatory lesions in the brain and spinal cord, particularly in the white matter.