Reye's syndrome

Reye's Syndrome 1990 case definition[23]Centers for Disease Control and Prevention. Reye syndrome: 1990 clinical case definition. 1990 [internet publication]. http://wwwn.cdc.gov/nndss/conditions/reye-syndrome/case-definition/1990

Reye's syndrome is defined as an illness that meets all of the following criteria:

• Acute, non-inflammatory encephalopathy with either sterile CSF containing <9 WBCs/mL or cerebral oedema without inflammation evident on histology

• Hepatic dysfunction documented by either a threefold elevation of serum transaminases and/or ammonia or liver biopsy demonstrating fatty infiltration

• No other diagnosis to account for the cerebral and hepatic derangement.

Clinical stages (modified from Hurwitz)[2]Hurwitz ES, Nelson DB, Davis C, et al. National surveillance for Reye syndrome: a five-year review. Pediatrics. 1982 Dec;70(6):895-900. http://www.ncbi.nlm.nih.gov/pubmed/7145544?tool=bestpractice.com

The US National Reye's Syndrome Surveillance System has described increasing stages of severity:

• Stage 1: Lethargic, vomiting

• Stage 2: Irritable, delirious, hyper-reflexive, positive Babinski's sign, dilated/sluggish pupils, responsive to pain

• Stage 3: Decorticate posturing, obtunded, unresponsive to pain

• Stage 4: Decerebrate posturing, comatose, fixed/dilated pupils

• Stage 5: Areflexia, flaccid paralysis, unresponsive pupils, seizures, respiratory failure

• Stage 6: Patient cannot be classified as he/she has been treated with curare or another medication that alters the level of consciousness.