Serum cholinesterase is an excellent biomarker of liver cirrhosis.

Background: Serum cholinesterase (ChE) is an enzyme synthesised by hepatocytes and its serum levels reflect the synthetic function of liver.

Methods: In patients with cirrhosis, liver function tests, PT INR and serum ChE levels were done within a week of enrolment. We studied 178 cirrhosis patients and 154 healthy controls prospectively. Receiver operator characteristics (ROC) curve analysis was employed to compute an optimal cut-off level to distinguish these groups. Correlation between ChE activity and serum bilirubin, albumin, PT INR and MELD score (Model for End-Stage Liver Disease) was analysed.

Results: Median serum ChE in cirrhotics was 1590 IU/L (110-8143) compared to controls 7886 IU/L (2022- 21673), p < 0.001. Serum ChE levels below 3506 had a 98.7% sensitivity and 80.3% specificity in predicting cirrhosis. Median serum ChE was higher (p < 0.001) in CC (n = 51) 4246 IU/L (680-8143) compared to DC (n = 127) 1324 IU/L (110-4550). ChE level less than 2385 IU/L had 80.1% sensitivity and 88.2% specificity in predicting DC. Follow-up levels in 25 patients showed good correlation with clinical course. The correlation coefficient between ChE and albumin was -0.67, 0.53 with PT INR and 0.59 with MELD score, (p < 0.001).

Conclusions: Serum ChE is an excellent biomarker of cirrhosis with good sensitivity and specificity. It shows good correlation with serum albumin, PT INR and MELD score. Since it distinguishes DC from CC well, low levels in cirrhosis may serve as a useful prognostic marker of advanced liver disease. Long-term follow-up studies are warranted to define its exact role in clinical practice.