Serum neuron-specific enolase, carnosinase, and their ratio in acute stroke. An enzymatic test for predicting outcome?
OBJECTIVE
Few admission variables adequately predict neuronal damage and prognosis in individual patients after stroke. Therefore, there is a need for a reliable non-invasive surrogate measure of clinical outcome.


METHODS
We have developed a surrogate measure of stroke outcome using the ratio of serum neuron-specific enolase (NSE) to human serum carnosinase (HSC) in 124 patients with acute ischemic or hemorrhagic stroke and 61 matched control subjects. Serum NSE is known to rise and HSC to fall after neuronal injury such as cerebral ischemia.


RESULTS
Serum NSE levels were significantly higher and HSC levels lower in the patient group. The NSE/HSC ratio was elevated in patients with stroke: median (semiquartile) hemorrhages, 0.072 (0.033); infarcts, 0.039 (0.026); and control subjects, 0.019 (0.014), P = .0001. Patients with a primary intracerebral hemorrhage had nonsignificantly higher ratios than those with an infarct (P = .082). The NSE/HSC ratio was significantly associated with 90-day outcome measured in two out of three disability and handicap scales: modified Barthel Index (rs = -.34, P = .001), modified Rankin Scale (rs = .30, P = .002), and Lindley Score (rs = .19, P = .057). Patients who died or were institutionalized had higher ratios than those who were discharged home: 0.069 (0.043) versus 0.038 (0.024), P = .011. Correlations between the NSE/HSC ratio and outcome were comparable to those between patient age or consciousness level on admission and clinical outcome.


CONCLUSIONS
We believe that measurement of NSE, HSC, or their ratio may be useful in the assessment of patients with acute stroke with respect to diagnosis and prediction of clinical outcome.
Stroke Research Group (Department of Medicine), King's College School of Medicine and Dentistry, London, UK.
R J
RJ
Butterworth
W S
WS
Wassif
R A
RA
Sherwood
A
A
Gerges
K H
KH
Poyser
J
J
Garthwaite
T J
TJ
Peters
P M
PM
Bath
D000208:Acute Disease; D000368:Aged; D002545:Brain Ischemia / Q000150:complications; D002543:Cerebral Hemorrhage / Q000150:complications; D002561:Cerebrovascular Disorders / Q000175:diagnosis* / Q000201:enzymology / Q000209:etiology; D004796:Clinical Enzyme Tests; D004150:Dipeptidases / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010751:Phosphopyruvate Hydratase / Q000097:blood*; D011237:Predictive Value of Tests; D011379:Prognosis; D013997:Time Factors
D004150:Dipeptidases; C019673:aminoacyl-histidine dipeptidase; D010751:Phosphopyruvate Hydratase