Neuron Specific Enolase (NSE)

NSE is an enzyme in humans encoded by the ENO2 gene. It is a phosphopyruvate hydratase. This enzyme is found in mature neurons and cells of neuronal origin, and is released after neuronal damage.

NSE has been studied as a marker for brain injury. Serum levels have been shown to be elevated in patients with stroke, correlates with the infarct volume and the degree of neurologic deficit. However, increase in serum NSE after brain injury occur late and lack sensitity and specificity.


  • Sensitivity 53%
  • Specificity 64%



Enolase 2. (2019). Retrieved from

González-García, S., González-Quevedo, A., Peña-Sánchez, M., Menéndez-Saínz, C., Fernández-Carriera, R., & Arteche-Prior, M. et al. (2012). Serum neuron-specific enolase and S100 calcium binding protein B biomarker levels do not improve diagnosis of acute stroke. The Journal Of The Royal College Of Physicians Of Edinburgh, 42(3), 199-204. doi: 10.4997/jrcpe.2012.302

UpToDate. (2019). Retrieved from

West Haven Criteria for Altered Mental Status in Hepatic Encephalopathy

West Haven criteria for altered mental status in hepatic encephalopathy

Grade 0 Minimal hepatic encephalopathy, lack of detectable changes in personality or behavior; no asterixis.

Grade 1 Trivial lack of awareness, shortened attention span, sleep disturbance, altered mood, and slowing the ability to perform mental tasks; asterixis may be present.

Grade 2 Lethargy or apathy, disorientation to time, amnesia of recent events, impaired simple computations, inappropriate behavior, and slurred speech; asterixis is present.

Grade 3 Somnolence, confusion, disorientation to place, bizarre behavior, clonus, nystagmus, and positive Babinski sign; asterixis usually absent.

Grade 4 Coma, lack of verbal, eye, and oral response to stimuli.


Emergency Management in Neurocritical Care: Chapter 17 Metabolic Encephalopathies, by Edward Manno