Other neuroimmunologic disorders
There are other rare neuroimmunologic disorders of the Central Nervous System (CNS) that The TM Society also supports. This includes any condition where immune-mediated inflammation causes damage to the myelin around the nerves in one or more places in the CNS (brain, spinal cord or optic nerves), so that the nerve can no longer conduct a good signal. The main ones are NMO and ADEM, but the definition of the various types of rare neuroimmunological disorders are evolving and expanding as categorising the differences becomes clearer. The differentiation between these disorders is determined by the location of the inflammatory attack, the pattern of organ involvement and the potential for recurrent events. This description makes the diagnosis sound more precise than it actually is since we are talking about a spectrum of disorders that sometimes change through time.
There is a Differential Diagnosis on the Transverse Myelitis Association (TMA) website for the following conditions: Transverse Myelitis (TM), Recurrent Transverse Myelitis (RTM), Neuromyelitis Optica (NMO), Longitudinally Extensive Transverse Myelitis (LETM), Multiple Sclerosis (MS) and Optic Neuroitis (ON).
Neuromyelitis Optica (NMO)
NMO, also known as Devics disease, involves immune-mediated inflammatory attacks in the spinal cord and/or the optic nerve. A person with NMO is at risk for multiple attacks of spinal cord inflammation or ON or both. There is ordinarily no brain involvement, but this is not always the case. There is a blood test for NMO that is clinically available although it is not 100% conclusive.
There is also a UK website called Devic's Disease that contains basic information on the disorder.
Acute Disseminated Encephalomyelitis (ADEM)
ADEM involves demyelination and inflammation in the brain and often inflammation in the spine cord and is usually monophasic.