<unk>  is a neurological condition involving severe damage to the myelin sheath of nerve cells in the pons (an area of the brainstem). It is predominately iatrogenic (treatment-induced), and is characterized by acute paralysis, dysphagia (difficulty swallowing), dysarthria (difficulty speaking), and other neurological symptoms.<unk>  was first described as a disorder in 1959. The original paper described four cases with fatal outcomes, and the findings on autopsy. The disease was described as a disease of alcoholics and malnutrition.<unk><unk> ’ indicated the site of the lesion and<unk> ’ was used to emphasise that myelin was affected. The authors intentionally avoided the term ‘demyelination’ to describe the condition, in order to differentiate this condition from multiple sclerosis and other neuroinflammatory disorders. Since this original description, demyelination in other areas of the<unk>  nervous system associated with osmotic stress has been described outside the pons (extrapontine). Osmotic demyelination syndrome is the term used for both<unk>  and extrapontine<unk> .<unk> , and osmotic demyelination syndrome, present most commonly as a complication of treatment of patients with profound hyponatremia (low sodium), which can result from a varied spectrum of conditions, based on different mechanisms. It occurs as a consequence of a rapid rise in serum tonicity following treatment in individuals with chronic, severe hyponatremia who have made intracellular adaptations to the prevailing hypotonicity.
Central pontine myelinolysis
Paraneoplastic cerebellar degeneration
Leukoencephalopathy
Bickerstaff brainstem encephalitis
Acute flaccid myelitis
Acute disseminated encephalomyelitis
Cerebellar stroke syndrome
Tropical neuropathy