Risk Factors And Etiological Characteristics Of Recurrence Of Primary Common Bile Duct Stones After ERCP

Purpose:This work aims to explore risk factors for the recurrence of primary common bile duct stones after ERCP operation.Related clinical records of the recurrent group are compared to those of the control group using statistical methods,so as to analyze the bile bacterial culture and drug sensitivity test on patients with common bile duct stones complicated with biliary infection.Methods:The data consists of the clinical records of 162 patients who had primary common bile duct stones were treated by means of Endoscopic Retrograde Cholangio-pancreatography in digestive endoscopy center,Changzheng Hospital of Second Military Medical Universityfrom January 2008 to October 2015.Supplement records gathered through telephone interviews and outpatient & inpatient visits are also considered.The analysis method includes two parts.Firstly,patient cases are divided into the recurrence group and the control group based on the diagnostic criteria for recurrent common bile duct stones.Secondly,analyzing the statistical significance of variables using unconditional logistic regression analysis.The univariate variables include age,gender,smoking history,drinking history,previous cholecystectomy,previous ERCP,routineblood test,liver function,renal function,coagulation function,electrolyte,lipidemia,juxtapapillary duodenal diverticulum,biliary infection,the character of stones,the number of stones and the size of stones.Lastly,multivariate analysis is adopted on significant variables to determine the risk factors associated with recurrent common bile duct stones.Following the diagnostic criteria for biliary infection,statistical methods are also applied on the results of the bile bacterial culture and drug sensitivity test on patients with common bile duct stones.Results:Among the 157 patients with primary common bile duct stones who have complete clinical data,105 of them are non-recurrent cases and 52 of them are recurrent cases.The median observation time is 42 months(the longest is 87 months,the shortest is 12 months).The univariate analysis showed that risk factors for recurrence of common bile duct stones include previous cholecystectomy(P=0.029),previous ERCP(P<0.001),biliary infection(P=0.018),the character of mixed sample stones(P<0.001),the size of stones(P=0.030).However the following factors whose P values are greater than 0.05 do not have much relation to recurrence of common bile duct stones: age(50-70 years,P=0.189;>70years,P=0.435),gender(P=0.214),smoking history(P=0.736),drinking history(P=0.665)and JPDD(P=0.413),the number of stones and laboratoryindex: WBC,N%,PLT,RBC,HB,TB,DB,Alb,ALT,AST,AKP,BUN,Cr,PT,INR,Na+,K+,Cl-,TRIG,TC,HBV.Multivariate analysis result onprevious ERCP(P<0.001;AOR=535.44,95% CI :49.66-5773.66)?biliary infection(P=0.047;AOR=2.534,95% CI:1.010-5.037)and the character of mixed sample stones(P=0.036;AOR=4.221,95% CI:1.099-16.207)present significant difference.Thus these three factors play particularly prominent role in the recurrence of common bile duct stones.Among all the 112 cases of bile bacterial culture,there were 70 cases with pathogenic bacteria in bile specimens.The positive rate was 62.50%(70/112).A total of 100 strains of bacteria were cultured,in which of gram negative bacteria accounts for 75 strains,gram positive bacteriaaccounts for 18 strains,fungi accounts for 7 strains.The top two bacteria were Escherichia coli 25 strainsand Klebsiella pneumonia 13 strains.Both Escherichia coli and Klebsiella pneumoniae have the highest drug resistance to Cefazolin,but they have a lower drug resistance rate than Cefoxitin and Amikacin.Conclusion:Previous ERCP,biliary infection and the character of mixed sample stones are independent risk factors for the recurrence of primary common bile duct stones.In bile bacteria culture which comes from the bile of patients with common bile duct stones complicated with biliary infection,gram negative bacteria are the most likely growing bacteria.Thus,antibiotics with a lower drug resistance rate on gram negative is the best first choice.