title: More often striatal myelinolysis than pontine? A consecutive series of patients with osmotic demyelination syndrome.
abstract: BACKGROUND
  Osmotic demyelination syndrome (ODS) is increasingly recognized to involve extrapontine locations in addition to the better-known central pontine myelinolysis.
  
  
  OBJECTIVE
  This study describes clinical and radiological features of consecutive  patients with ODS detected over 1 year.
  
  
  METHODS
  Patients fulfilling clinical and radiological criteria for ODS were prospectively enrolled and were followed with serial assessments during hospital stay and up to 253 days after discharge.
  
  
  RESULTS
  Eight patients (five females)  aged 24-89 years were enrolled, comprising 0·06% of all admissions to the general medical and neurology services. All had preceding hyponatraemia and hypokalaemia of various aetiologies. One patient developed ODS after postpartum pituitary haemorrhage, which has been reported  only rarely. Sodium levels were corrected at maximal rates exceeding 8 mmol/l/day. Neurological symptoms attributed to ODS began 3-15 days after clinical improvement following sodium correction in four patients; the remainder did not show any intervening lucent interval. Fifty per cent  were stuporous at admission, 50% had seizures, 62·5% had symmetric parkinsonism, and 75% had prominent primitive reflexes. Stretch reflexes were absent in 25% and normal or brisk in the remainder. Magnetic resonance imaging (MRI) showed symmetric striatal lesions in all patients, with  concomitant pontine involvement in only 25%. Four patients had poor outcomes (modified Rankin score >3), with prognosis dependent on the presence of severe systemic illness, liver dysfunction, encephalopathy, seizures, and degree of disability upon discharge from hospital. Patients with  parkinsonism responded to dopaminergic therapy, with chorea, dystonia, and depression as later developments. This series is remarkable for the high incidence of extrapontine lesions, much more common than pontine involvement.
authors.affiliation: Department of Neurology, Goa Medical College, India. adesouza1@gmail.com
authors.forename: Aaron
authors.initials: A
authors.lastname: de Souza
authors.forename: Paresh K
authors.initials: PK
authors.lastname: Desai
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003342:Corpus Striatum / Q000473:pathology*; D003681:Dehydration / Q000150:complications* / Q000473:pathology; D005260:Female; D006801:Humans; D007008:Hypokalemia / Q000150:complications / Q000473:pathology; D007010:Hyponatremia / Q000150:complications / Q000473:pathology; D008297:Male; D008875:Middle Aged; D017590:Myelinolysis, Central Pontine / Q000209:etiology / Q000473:pathology*; D009995:Osmosis; D013577:Syndrome; D055815:Young Adult