Evaluation of Monoethylglycinexylidide as a Quantitative Index ofHepatic Function in Patients with Primary Hepatoma

Background :Quantitative assessment of liver function is essential prior to operation, as hepatic reserve function has significant influence on prognosis after hepatic resection. The conventional liver function tests do not quantitate hepatic function but rather assess the presence or absence of hepatobiliary injury. Lidocaine is metabolited to form monoethylglycinexylidide (MEGX) via oxidative N-deethylation by the hepatic cytochrome P-450 system. Metabolic rate of lidocaine could be used in quantitative assessment of liver function. The purpose of this study is to assess the liver function by MEGX and to determine the cut-off level of MEGX concentration to differentiate normal subjects from patients with primary hepatoma, and to compare MEGX test with other liver function teats. Method :From Jun. 1996 to Oct. 1996, 9 inpatients with primary hepatoma admitted to Severance Hospital were entered into this study as patient group. 17 healthy volunteers with normal hepatic biochemical tests and absence of HBsAg and anti-HCV were included as controls. A bolus injection of lidocaine (1 mg/kg) was intravenously administered for 1 min. Venous bloods were taken before and 15 minutes after the bolus injection to determine MEGX and lidocaine concentrations. The MEGX and lidocaine concentrations in the serum were measured using a fluorescence polarization immunoassay with a TDx analyzer (Abbott Laboratories, Chicago, IL, USA) Result :Reference interval for normal controls was 41.4-64.0 ng/mL. The serum MEGX concentration significantly decreased in patients with primary hepatoma compared to controls. It also showed that patients with primary hepatoma associatd with cirrhosis has lower MEGX concentration than patients only with primary hepatoma. The MEGX concentration was proportional to the serum albumin level and inversely proportional to the prothrombin time and ICGR15. As we selected cut-off value of MEGX concentration, 20 ng/mL as an indicator of hepatic dysfuction in patients with primary hepatoma assoclated with cirrhosis, its clinical sensitivity and specificlty were 100% and 100%, respectively. Conclusion :The measurement of? MEGX concentration 15 minutes after lidocaine injection may serve as a simple and rapid quantitative liver function test, and reflect the severity of liver dysfunction in patients with primary hepatoma associated with cirrhosis. Further prospective studies in the cases with chronic liver diseases and primary hepatoma will be needed for the difference of MEGX concentration between the sexes, correlation with survival rate and also to establish the cut-off level of MEGX concentration for resectability and types of liver resectionope