Abstract: Objective:To investigate the diagnostic value of serum liver function indexes for gallbladder stones combined with asymptomatic secondary common bile duct stones.
Methods:The retrospective cohort study was conducted. The clinical data of 460 patients with gallbladder stones who were admitted to the Affiliated Hospital of Zunyi Medical College from June 2012 to June 2016 were collected. Of 460 patients, 106 combined with asymptomatic secondary common bile duct stones and 354 with gallbladder stones were allocated into the common bile duct stone group and gallbladder stone group, respectively. The serum liver function test was applied to the 2 groups, including alanine transaminase (ALT), aspartate transaminase (AST), total bilirubin (TBil), direct bilirubin (DBil), glutamyltransferase (GGT) and alkaline phosphatase (ALP). The receiver operating characteristic (ROC) curve was built using significant statistical indicators, and correspondent cutoff value, sensitivity and specificity were calculated according to ROC curve. Observation indicators: (1) comparison of serum liver function indicators (ALT, AST, TBil, DBil, GGT, ALP) between the 2 groups; (2) analysis result of ROC curve. Measurement data with normal distribution was represented as ±s. The comparison between groups was evaluated with the independentsample t test. The comparison of count data were analyzed using the chisquare test. The ROC curve analysis was done for significant statistical indicators.
Results: (1) Comparison of serum liver function indicators between the 2 groups, the levels of ALT, AST, TBil and DBil were (32±8)U/L, (35±8)U/L, (12.8±2.5)μmol/L, (2.6±0.4)μmol/L in the common bile duct stone group and (30±7)U/L, (32±7)U/L, (12.2±2.4)μmol/L, (2.5±0.4)μmol/L in the gallbladder stone group, respectively, with no statistically significant difference (t=0.891, 0.786, 0.924, 1.026, P>0.05). The levels of GGT and ALP were (162± 43)U/L and (145±37)U/L in the common bile duct stone group and (36±10)U/L and (128±23)U/L in the gallbladder stone group, respectively, with significantly statistical differences (t=20.859, 2.483, P<0.05). (2) Result of ROC curve showed that areas under the curve of GGT and ALP were respectively 0.963 ［95% confidence interval (CI): 0.938-0.988］ and 0.621 (95%CI: 0.561-0.684). The correspondent cutoff value of diagnostic accuracy, sensitivity and specificity of GGT and ALP were 92.5 U/L and 139.5 U/L, 91.6% and 50.7%, 95.7% and 76.5%, respectively.
Conclusion:The abnormally elevated levels of serum GGT have major diagnostic value for patients with gallbladder stones combined with asymptomatic secondary common bile duct stones, with an advantage of convenient and fast operation, and it is worth to be applied and popularized.