Study Of The Role Of Bacteria In The Pathogenesis Of Cholesterol Gallstone Formation

Cholesterol gallstone disease remains a common cause of serious morbidity and mortality.The natural history of cholesterol gallstone pathogenesis is not thoroughly understood Many studies suggested that cholesterol gallstone formation related to the disorder of bile metabolism and gallbladder contractility. But little attention has been payed to bacteria. Recently rich amount of bacteria DNA had been found in most cholesterol gallstones, which indicates a possible link between bacteria and cholesterol gallstone formation.Our study is the first one to detect and quantify the bacteria DNA from gallstone,gallbladder mucosa, gallbladder bile in cholesterol gallstone patients and from gallbladder mucosa, gallbladder bile in non-gallstone patients, coupled with the correlation with immunoglobulins concentration in bile and gallbladder mucosa. We are also the first one to observe the influence of bacteria found in cholesterol gallstones on the cholesterol nucleation time(NT) to find out the lithogenic ones, and study their influence on the thermodynamic balance of bile system, explore the source and mechanism of their pronucleation activity.The first part The comparison of bacterial infection state between cholesterol gallstone patients and non-gallstone individues, and the correlation with immunoglobulins concentration in bile and gallbladder mucosa[Aim]: The frequence of bacteria DNA detected with PCR in cholesterol gallstones is much higher than the culture results. To evaluate the status of bacteria in cholesterol gallstone pathogenesis, we compare the bacterial infection state between cholesterol gallstone patients and non-gallstone individues, coupled with the correlation with immunoglobulins concentration in bile and gallbladder mucosa. [Methods): Culture independent, half-quantitative PCR and comparative 16S rRNA analysis were used to detect bacteria from gallstones, bile and gallbladder mucosa in 38 cholesterol gallstone patients and 17 non-gallstone individuals. IgA, IgM, IgG concentrations of bile andgallbladder mucosa were also measured parallelly by the method of nephelometry. [Results]: 1. The positive rate of bacteria DNA in bile of gallstone patients and controls was 77% and 67%, with concentrations of 3.23 cfu(log value) and 2.43 cfu respectively. The positive rate of bacteria DNA in mucosa was 64% and 69%,with concentrations of 3.28cfu and 3.67 cfu respectively. No significant difference existed between two groups, including the concentrations of immunoglobulin(P>0.05). No positive correlation was observed between immunoglobulin and bacteria concentrations. 2. The positive rate of bacteria in core and periphery part of gallstones was 79% and 82%, with bacteria concentrations of 3.19 cfu and 3.26 cfu respectively. All three pure cholesterol stones harbored trace of bacterial DNA. No positive correlation existed between the incidence of bacteria and the percentage of cholesterol in the stone. 3. There was a sharp distinction for mucosa IgA, IgG concentrations between mucosa bacteria positive and negative ones in gallstone patients(P<0.05).4. The bile bacteria concentrations fell significantly after accepting a dosage of antibiotics right before operation, while no change on core or periphery part of gallstone and mucosa was observed. 5. The bacteria sequences in cholesterol gallstone group included Propionibacterium acne, E.coli, Pseudomonas aeruginosa, Streptococcus, Acinetobacter, Sphingmonas, Bacteroides fragilis. Cholesterol gallstone group had more bacteria sequences than non-gallstone group, most of sequences in latter group could be found in cholesterol gallstone group. [Conclusions]: 1 .There is a similar biliary infection rate between gallstone patients and controls. Bacteria found in biliary tract is not sufficient to draw a definite link to cholesterol gallstone formation. 2. However, The cholesterol group has more bacteria sequences than the non-gallstone group, some of which overlapped in two groups. 3.The bacteria on mucosa maybe indirectly lithogenic through IgAJgG content increa...