Genomewide scans of inbred strains of mice have linked the genes encoding the hepatocanalicular cholesterol transporter ABCG5/G8 to gallstone formation. Five nonsynonymous coding single-nucleotide polymorphisms (SNPs) in the orthologous human genes are associated with differences in serum cholesterol and plant sterol levels. We now tested these ABCG5/G8 SNPs for linkage and association with gallstone susceptibility in humans. Prospectively, we collected data from 178 white individuals with gallbladder stones or history of cholecystectomy in 84 families and from 70 stone-free controls, as confirmed by abdominal ultrasound. We performed nonparametric linkage (NPL) analysis of affected sib pairs (ASPs) and association tests of cases and controls. In ASPs, gallstones were strongly linked to the D19H variant of the ABCG8 gene (NPL score ‫؍‬ 7.1; P ‫؍‬ 4.6 ؋ 10 ؊13 ). The risk of gallstones in carriers of the 19H allele was significantly increased in randomly selected cases from the ASP cohort compared to the stone-free controls (OR ‫؍‬ 3.018; P ‫؍‬ 0.017). Consistent with the mouse model, heterozygosity for the lithogenic ABCG8 allele was associated with gallstones in humans; 21.4% of gallstone patients carried the heterozygous D19H genotype, compared with 8.6% of controls (OR ‫؍‬ 2.954; P ‫؍‬ 0.026). Conclusion: The linkage and association studies identified the cholesterol transporter ABCG5/G8 as a genetic determinant of gallstone formation, or LITH gene, in humans. The function of this transporter and the results of the genetic study taken together indicate that in gallstone-susceptible carriers of the ABCG8 19H allele, cholesterol cholelithiasis is secondary to increased hepatobiliary cholesterol secretion. (HEPATOLOGY 2007;46:793-801.)

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Gallstones occur in about one third of the patients having liver cirrhosis. Pigment gallstones are the most frequent type, while cholesterol stones represent about 15% of all stones in cirrhotics. Increased secretion of unconjugated bilirubin, increased hydrolysis of conjugated bilirubin in the bile, reduced secretion of bile acids and phospholipds in bile favor pigment lithogenesis in cirrhotics. Gallbladder hypomotility also contributes to lithogenesis. The most recent data regarding risk factors for gallstones are presented. Gallstone prevalence increases with age, with a ratio male/female higher than in the general population. Chronic alcoholism, viral C cirrhosis, and non-alcoholic fatty liver disease are the underlying liver diseases most often associated with gallstones. Gallstones are often asymptomatic, and discovered incidentally. If asymptomatic, expectant management is recommended, as for asymptomatic gallstones in the general population. However, a closer follow-up of these patients is necessary in order to earlier treat symptoms or complications. For symptomatic stones, laparoscopic cholecystectomy has become the therapy of choice. Child-Pugh class and MELD score are the best predictors of outcome after cholecystectomy. Patients with severe liver disease are at highest surgical risk, therefore gallstone complications should be treated using noninvasive or minimally invasive procedures, until stabilization of the patient condition.

We evaluated the prevalence and the risk factors for gallstone disease in patients with chronic hepatitis C infection. We investigated 453 consecutively admitted patients with chronic infection with hepatitis C virus (HCV) (cirrhosis excluded) and 879 patients without liver disease (October 2006-April 2007). Gallstone disease was diagnosed if gallstones were present at ultrasonography or if there had been a previous cholecystectomy. Variables evaluated were age, gender, gallstone heredity, body mass index, waist circumference, parity, serum lipids, fatty liver, arterial hypertension, diabetes mellitus and metabolic syndrome (International Diabetes Federation criteria). Informed consent was obtained from all patients. We found that 88 of 453 (19%) patients with chronic HCV hepatitis (age 50.1 +/- 11.7 years) and 153 of 879 (17%) controls (age 60.6 +/- 12.6 years) had gallstone disease (GD). Abdominal obesity (OR = 2.108, 95% CI 1.287-3.452) and steatosis (OR = 3.699, 95% CI 2.277-6.008) were risk factors for GD in HCV patients. Gallstone heredity, dyslipidaemia, type 2 diabetes mellitus and metabolic syndrome increased the risk for GD in controls vs HCV patients. Our study shows that even HCV patients with chronic hepatitis but not cirrhosis have an increased prevalence of gallstones. Compared with controls, gallstones are present in HCV patients at a younger age and are associated with central obesity and liver steatosis, but not with gallstone heredity, dyslipidaemia, diabetes mellitus or metabolic syndrome. Although we could not establish a temporal relationship, the association between HCV infection and gall stone disease is real and appears to be causally linked, at least in predisposed individuals (obese and with liver steatosis).

Background and aim-An impaired contractility has been suggested as a contributor to the increased incidence of gallstones in liver cirrhosis, but the few studies on gall bladder emptying in cirrhotics offered contradictory results. Ingestion of a meal triggers the physiological pathway of gall bladder emptying; therefore, it was decided to analyse postprandial kinetics by investigating simultaneously the rates of gastric and gall bladder emptying of a mixed meal in patients with liver cirrhosis. Methods-Gastric and gall bladder emptying were measured using ultrasound techniques after a solid-liquid meal (14 g fat, 425 kcal) in 24 patients with liver cirrhosis and in 12 controls. None of the subjects had gall bladder disease. Sequential changes in cross sectional area of the gastric antrum and in gall bladder volume were represented as a monoexponential process after the test meal. Cirrhotic patients were analysed according to the severity of disease (Child classes). The presence of portal gastropathy was assessed by endoscopy. Differences between groups were assessed using the two tailed Student's t test for unpaired observations and the correlations by linear regression (Pearson's coefficient

An increased prevalence of gallstones was demonstrated in patients with liver cirhosis, higher in the advanced stages of the disease. Some studies have found impaired emptying of the gallbladder in cirrhotic patients. Our aim here was to investigate gallbladder emptying in cirrhotic patients with and without gallstones to find out whether emptying is further impaired in the presence of gallstones. The study group comprised 24 patients with liver cirrhosis and gallstones, 8 in each Child class. The controls were represented by 18 cirrhotic patients without gallstones, 6 in each Child class. Fasting gallbladder volume was calculated by ultrasound using the ellipsoid formula. Gallbladder emptying was evaluated for 90 min after ingestion of a solid-liquid meal (14 g fat, 425 kcal), by assessing minimal residual volume, gallbladder ejection fraction, and area under emptying curve at 15-min intervals. Statistical analysis was performed using the two-tailed Students' t test and Pearson's correlation coefficient. In controls, gallbladder fasting and residual volumes increased with the severity of cirrhosis, but gallbladder emptying did not change significantly. In cirrhotics with gallstones, gallbladder emptying decreased in Child C compared with Child A class patients and, also, compared to Child C controls. The number or size of gallstones, as well as the thickness of the gallbladder wall, did not correlate with gallbladder emptying parameters. Gallbladder contractility is impaired in patients with liver cirrhosis and gallstones. Hypomotility is proportional to the severity of liver disease. Gallbladder hypomotility might contribute to the increased gallstone formation in patients with advanced cirrhosis.