A population study on the prevalence of gallstone disease: the Sirmione Study

Bile duct stone procedures are more frequent in patients with hypothyroidism. A large, registry-based, cohort study in Finland

OBJECTIVE

Delayed bile flow may induce the formation/accumulation of common bile duct stones (CBDS). Bile flow is delayed in hypothyroidism, partly due to insufficient sphincter of Oddi relaxation. Patients with CBDS have higher incidences of clinical and subclinical hypothyroidism compared to healthy controls and gallbladder stone patients. The aim of this large registry-based study was to investigate the prevalence of CBDS in patients with diagnosed hypothyroidism compared to age-, sex- and living area-adjusted glaucoma (control) patients.

MATERIAL AND METHODS

Between 1987 and 2001, all patients with approved Special Medical Coverage (SMC) for hypothyroidism or glaucoma, and without other SMC approvals, were included. The glaucoma (control) cohort was adjusted for age, sex and area of residence. For each patient, onset of SMC, all prescription drugs and treatments for CBDS were noted.

RESULTS

A total of 14,334 patients in each group met the inclusion criteria. Thirty-three patients (0.23%) in the hypothyroidism cohort and 23 (0.16%) in the glaucoma cohort had been treated for CBDS (p = 0.018). The groups did not differ in the number of CBDS treatments before the diagnosis of hypothyroidism or glaucoma. However, after the diagnosis of hypothyroidism or glaucoma there were significantly more CBD stone patients in the hypothyroid cohort (n = 25) than in the glaucoma cohort (n = 14) (p < 0.05).

CONCLUSIONS

Diagnosed hypothyroidism is a significant risk factor for CBDS. We hypothesize that CBD stone formation begins during the untreated period and develops/matures even after the medication has been initiated, raising the question of the efficiency of treatment in this respect. When treating CBDS patients, one should be aware of the possible hypothyroid background.

Risk factors, complications, and outcomes of gallstones in children: a single-center review

BACKGROUND AND OBJECTIVE

The increasing use of sonography has resulted in an increase in the proportion of children with gallstones who are asymptomatic at the time of diagnosis. In adults, the literature supports expectant management of clinically silent gallstones. The evidence for this management approach in children is limited to a number of small series. Our objective was to review the risk factors, complications, and outcomes of gallstones at our institution, particularly in those patients who are asymptomatic at the time of initial diagnosis.

MATERIALS AND METHODS

We reviewed 382 cases of gallstones in children. These patients were diagnosed with sonography. Data on age at diagnosis, presentation, sonographic findings, risk factors, complications, surgery, and follow-up were collected. A chi2 test was used to compare the complication rates between symptomatic and asymptomatic groups. Descriptive statistics were used to analyze the sample.

RESULTS

At diagnosis, 50.5% of children were asymptomatic; these patients were diagnosed at a mean age of 8.23 years. Compared with symptomatic patients, they were less likely to have a hemolytic anemia but more likely to have other risk factors, including cardiac surgery, leukemia and lymphoma, short bowel syndrome, or exposure to total parenteral nutrition or cephalosporins. These patients had a lower rate of complications than the symptomatic patients (4.6% vs 28.2% of symptomatic, P < 0.0001) and only 3.1% developed symptoms that necessitated surgery (vs 59.0% of symptomatic). Of the 58 (15.1%) diagnosed in infancy, 47 (81.0%) were asymptomatic. The infant group also had low rates of complications (8.6%) and cholecystectomy (1.7%). In cases with sonographic follow-up, resolution of gallstones was demonstrated in 16.5% of asymptomatic patients and in 34.1% of infants.

CONCLUSIONS

The data suggest that clinically silent gallstones in children and infants are associated with low rates of complications and can be managed conservatively, unless complications occur. Patients with sickle cell disease, spherocytosis, and elliptocytosis had high complication rates and required surgery more often.

Prospective observational study of the incidental findings on endoscopic ultrasonography: should a complete exploration always be performed?

OBJECTIVES

To quantify the additional non-suspected new diagnoses made on upper endosonography (EUS) which were unknown before the procedure, and to analyse their influence on the management of patients. A further objective was to evaluate the influence that previous radiological or endoscopic explorations have on the capacity of EUS to diagnose these unsuspected lesions.

MATERIAL AND METHODS

During a 2-year period every patient sent to our unit for upper EUS underwent a complete investigation, after signing an informed consent document. An upper EUS was considered as complete whenever the gut wall, pancreas, biliary tract, ampulla, large abdominal vessels, liver, spleen, left adrenal gland, posterior mediastinum and thyroid lobes had been explored. An additional diagnosis (AD) was defined as a diagnosis made on EUS that was previously unknown and not suspected. A significant additional diagnosis (SAD) was defined as an AD that required further study. The results of complementary explorations carried out before EUS were registered.

RESULTS

A total of 239 patients were included in the study. ADs were found in 92 patients (38.5%), which were considered to be SADs in 27 patients (11.3%). Those patients had previously undergone computed tomography (CT) and those who underwent more than one exploration had fewer incidences of ADs on EUS (p=0.03 and p=0.02, respectively). No exploration alone or in combination with others showed any influence on the capacity of EUS to find a SAD (p >0.05).

CONCLUSIONS

In our series, an AD was found on upper endosonography in 38.5% of the patients studied, and a SAD in 11.3%. The probability of finding a SAD on EUS is not influenced by previous endoscopic or radiologic explorations.

Incidence of and potential risk factors for gallstone disease in a general population sample

BACKGROUND

Several epidemiological studies have been published, but there are few reports on relations between gallstone incidence, symptomatology and risk factors.

METHODS

Of 621 randomly selected individuals aged 35-85 years in a general population who had been screened previously with ultrasonography and found to have no gallbladder stones, 503 (81.0 per cent) were re-examined after a minimum interval of 5 years. At baseline and re-examination, heredity for gallstone disease was explored and body mass index, digestive symptoms including abdominal pain, quality of life, alcohol and smoking habits, use of non-steroidal anti-inflammatory drugs and oestrogen, parity and blood lipid levels were recorded.

RESULTS

Forty-two (8.3 per cent) of the 503 subjects developed stones. Subjects were followed for a total of 3025.8 person-years, yielding an incidence for newly developed gallstones of 1.39 per 100 person-years. A positive association for gallstone development was found only for length of follow-up and plasma low-density lipoprotein-cholesterol levels at baseline. Weekly alcohol consumption was inversely related to gallstone development.

CONCLUSION

The incidence of gallstones in this population was 1.39 per 100 person-years. Gallstone development was related to length of follow-up and LDL-cholesterol levels, and inversely related to alcohol consumption.

The prevalence and risk factors for gallstone disease

Gallstone disease is one of the most prevalent gastrointestinal disorders. In addition, the costs associated with the diagnosis and treatment of gallstone disease have been rapidly increasing. The etiology and pathogenesis of gallstone disease remains incompletely understood. Gallstone formation may result from a complex interaction of genetic and environmental factors. This article reviews the prevalence and risk factors associated with gallstone disease. Understanding the pathogenesis of gallstone disease could lead to the development of better therapeutic and preventive strategies for dealing with this disease.

Spontaneous gallbladder pathology in baboons

BACKGROUND

Gallbladder pathology (GBP) is a relatively uncommon, naturally occurring morbidity in both baboons and humans.

METHODS

A retrospective analysis was performed on 7776 necropsy reports over a 20 year period to determine the prevalence of baboon GBP.

RESULTS

Ninety-seven cases of GBP were identified, yielding a 20 year population prevalence of 1.25%. GBP is more common in adult female baboons, occurring with a female to male ratio of nearly 2:1. Among gallbladder pathologies, cholecystitis (35.1%) and cholelithiasis (29.9%) were the most prevalent abnormalities, followed by hyperplasia (16.5%), edema (15.5%), amyloidosis (5.2%), fibrosis (4.1%), necrosis (4.1%), and hemorrhage (1.0%).

CONCLUSION

Many epidemiologic similarities exist between GBP in baboons and humans suggesting that the baboon may serve as a reliable animal model system for investigating GBP in humans.

New insights into the molecular mechanisms underlying effects of estrogen on cholesterol gallstone formation

Epidemiological and clinical studies have found that at all ages women are twice as likely as men to form cholesterol gallstones, and this gender difference begins since puberty and continues through the childbearing years, which highlight the importance of female sex hormones. Estrogen is a crucial hormone in human physiology and regulates a multitude of biological processes. The actions of estrogen have traditionally been ascribed to two closely related classical nuclear hormone receptors, estrogen receptor 1 (ESR1) and ESR2. Recent studies have revealed that the increased risk for cholesterol gallstones in women vs. men is related to differences in how the liver metabolizes cholesterol in response to estrogen. A large number of human and animal studies have proposed that estrogen increases the risk of developing cholesterol gallstones by increasing the hepatic secretion of biliary cholesterol, which, in turn, leads to an increase in cholesterol saturation of bile. Furthermore, it has been identified that hepatic ESR1, but not ESR2, plays a major role in cholesterol gallstone formation in mice in response to high doses of 17beta-estradiol. The mechanisms mediating estrogen's action have become more complicated with the recent identification of a novel estrogen receptor, G protein-coupled receptor 30 (GPR30), a member of the seven-transmembrane G protein-coupled receptor superfamily. In this review, we provide an overview of the evidence for the lithogenic actions of estrogen through ESR1 and discuss the cellular and physiological actions of GPR30 in estrogen-dependent processes and the relationship between GPR30 and classical ESR1 on gallstone formation.

Evaluation and management of functional biliary pain in patients with an intact gallbladder

The diagnosis and management of suspected functional biliary pain in patients with an intact gallbladder remains contentious. Major issues include the lack of a clear definition of what constitutes biliary pain, a poor understanding of its natural history and pathophysiology, and the all too common scenario of the patient who has persistent pain despite surgical removal of the gallbladder. As a consequence, symptoms alone have generally been considered to be unreliable in the diagnosis of gallbladder dysfunction, and this has led to a search for a reliable test to help confirm a clinical suspicion of gallbladder dysfunction prior to the definitive treatment, cholecystectomy. At present, cholecystokinin-cholescintigraphy with a calculation of the gallbladder ejection fraction is the most commonly used test; however, its utility in predicting symptom outcome after cholecystectomy has been questioned. The use of cholecystokinin-cholescintigraphy to determine the appropriateness for cholecystectomy appears to be most useful when performed using a slow infusion of cholecystokinin in a well-selected patient population. However, for reasons explained herein, consideration of cholecystectomy on the basis of high clinical suspicion after adequate follow-up with trials of pharmacological therapies and exclusion of other disease entities, together with counseling the patient on postoperative expectations, may be a reasonable alternative.

Mandatory and optional function tests for biliary disorders

Function tests in gastroenterology and hepatology aim to provide criteria for diagnosis of specific disorders and for prediction of patient responses to therapy. This review focuses on the utility of function tests in the management of gallstone disease and functional biliary disorders. In gallstone disease, function tests may be considered in the selection of candidates for nonsurgical therapy of gallbladder stones only. In cases of suspected functional biliary disorders, experts have advocated the use of classical noninvasive tests such as hepatobiliary scintigraphy. However, unequivocal evidence for their utility in diagnosis or patient selection for invasive treatment is yet to be provided. Recently, more advanced noninvasive tests such as real-time ultrasonography or secretin-stimulated magnetic resonance cholangiopancreaticography have been described. Controlled trials using these novel techniques may provide a rationale for the use of function tests in clinical management of calculous and acalculous biliary diseases, but are currently not available.

Gender and metabolic differences of gallstone diseases

AIM: To investigate the risk factors for gallstone disease in the general population of Chengdu, China.

METHODS: This study was conducted at the West China Hospital. Subjects who received a physical examination at this hospital between January and December 2007 were included. Body mass index, blood pressure, fasting plasma glucose, serum lipid and lipoproteins concentrations were analyzed. Gallstone disease was diagnosed by ultrasound or on the basis of a history of cholecystectomy because of gallstone disease. Unconditional logistic regression analysis was used to investigate the risk factors for gallstone disease, and the Chi-square test was used to analyze differences in the incidence of metabolic disorders between subjects with and without gallstone disease.

RESULTS: A total of 3573 people were included, 10.7% (384/3573) of whom had gallstone diseases. Multiple logistic regression analysis indicated that the incidence of gallstone disease in subjects aged 40-64 or ≥ 65 years was significantly different from that in those aged 18-39 years (P < 0.05); the incidence was higher in women than in men (P < 0.05). In men, a high level of fasting plasma glucose was obvious in gallstone disease (P < 0.05), and in women, hypertriglyceridemia or obesity were significant in gallstone disease (P < 0.05).

CONCLUSION: We assume that age and sex are profoundly associated with the incidence of gallstone disease; the metabolic risk factors for gallstone disease were different between men and women.

Lithogenesis and bile metabolism

Gallstone disease exacts a considerable financial and social burden worldwide leading to frequent physician visits and hospitalizations. Based on their composition, gallstones are categorized as cholesterol, black pigment, and brown pigment, with each category having a unique structural, epidemiologic, and risk factor profile. Cholesterol crystal formation requires the presence of one or more of the following: (a) cholesterol supersaturation, (b) accelerated nucleation, or (c) gallbladder hypomotility/bile stasis. Some risk factors for cholesterol stones include age, gender, genetics, obesity, rapid weight loss, and ileal disease. Generally, pigment stones are formed by the precipitation of bilirubin in bile, with black stones associated with chronic hemolytic states, cirrhosis, Gilbert syndrome, or cystic fibrosis, and brown stones associated with chronic bacterial or parasitic infections.

Biliary dyskinesia

Functional disorders of the biliary tract include gallbladder dyskinesia (GBD) and sphincter of Oddi dysfunction (SOD). The diagnosis of GBD is made if the gallbladder ejection fraction is less than 35% to 40% using cholecystokinin cholescintigraphy. Despite slightly inferior outcomes compared with calculous disease, patients who have GBD should be treated with cholecystectomy. SOD is most often noted in the postcholecystectomy patient and symptoms can be biliary or pancreatic in nature. The gold standard for diagnosis remains manometry, with basal biliary or pancreatic sphincter pressures measuring greater than 40 mm Hg. Patients who have increased pressures may benefit from endoscopic sphincterotomy.

Incidence of gallstone disease in Italy: Results from a multicenter, population-based Italian study (the MICOL project)

AIM: To evaluate gallstone incidence and risk factors in a large population-based study.

METHODS: Gallstone incidence and risk factors, were evaluated by structured questionnaire and physical examination, respectively, in 9611 of 11 109 (86.5%) subjects who were gallstone-free at the cross-sectional study.

RESULTS: Six centers throughout Italy enrolled 9611 subjects (5477 males, 4134 females, aged 30-79 years), 9517 of whom were included into analysis: 424 subjects (4.4%) had gallstones and 61 (0.6%) had been cholecystectomized yielding a cumulative incidence of 0.67% per year (0.66% in males, 0.81% in females). Increasing age, a high body mass index (BMI), a history of diabetes, peptic ulcer and angina, and low cholesterol and high triglyceride levels were identified as risk factors in men while, in females, the only risk factors were increasing age and a high BMI. Increasing age and pain in the right hypochondrium in men and increasing age in females were identified as predictors of gallstones. Pain in the epigastrium/right hypochondrium was the only symptom related to gallstones; furthermore, some characteristics of pain (forcing to rest, not relieved by bowel movements) were significantly associated with gallstones. No correlation was found between gallstone characteristics and clinical manifestations, while increasing age in men and increasing age and BMI in females were predictors of pain.

CONCLUSION: Increasing age and BMI represent true risk factors for gallstone disease (GD); pain in the right hypochondrium and/or epigastrium is confirmed as the only symptom related to gallstones.

Patients with iron deficiency anemia have an increased prevalence of gallstones

We determined the frequency of gallstones (GS) in iron deficiency anemia (IDA) patients and evaluated factors that could affect GS formation-like lipid levels and gallbladder (GB) motilities of the patients. One hundred and eleven IDA patients (88 females, 23 males; median age, 42) and 81 healthy controls (68 females, 13 males; median age, 42) were included into our study. The clinical findings of all IDA patients were recorded down; biochemical values and body mass index (BMI) were determined; and abdominal ultrasonography was performed. In addition, GB emptying was monitored by ultrasound at 30-min intervals for 2 h after a mixed meal in randomly chosen, age-matched 25 IDA patients and 26 controls. Fasting volume (FV), residual volume (RV), and ejection fraction (EF) for all GBs were determined. The frequency of GS plus cholecystectomy was significantly higher in IDA patients (15 cases, 13.5%) than in the control group (five cases, 6.2%, p = 0.048). IDA patients with GS plus cholecystectomy were older than those without GS plus cholecystectomy (p < 0.001). FV and EF did not differ between IDA and control groups (p > 0.05). On the other hand, RV was significantly higher in IDA group than in controls (p = 0.035). The frequency of GS in IDA patients was significantly higher than in controls. The increased prevalence of GS in IDA might be explained with impaired GB motility.

Increased prevalence of gallstone disease and impaired gallbladder motility in patients with Barrett's esophagus

The prevalence of gallstones in patients with Barrett's esophagus (BE) and their gallbladder motility relative to that of healthy volunteers and GERD patients without BE were investigated. Of the 707 patients reviewed, 203 (125 males and 78 females) had BE. The prevalence of gallstones was significantly higher in the patients with BE than in those without BE (34 vs. 20%, respectively). The gallbladder functions of 22 patients with GERD, 27 patients with BE and 21 healthy volunteers were assessed by ultrasonography before and after a test meal. The patients with BE had significantly higher fasting volume and residual volume, but lower ejection volume, ejection fraction and ejection rate values than those of the healthy controls. None of the ultrasonographic parameters of patients without BE were significantly different from those of the controls. Patients with BE have a more complex gastrointestinal motility disorder that involves the gallbladder, and this makes this subset of patients with GERD more prone to gallstone disease.

Insulin resistance is associated with gallstones even in non-obese, non-diabetic Korean men

It remains unclear as to whether insulin resistance alone or in the presence of wellknown risk factors, such as diabetes or obesity, is associated with gallstones in men. The aim of this study was to determine whether insulin resistance is associated independently with gallstone disease in non-diabetic men, regardless of obesity. Study subjects were 19,503 Korean men, aged 30-69 yr, with fasting blood glucose level <126 mg/dL and without a documented history of diabetes. Gallbladder status was assessed via abdominal ultrasonography after overnight fast. Body mass index and waist circumference were measured. Insulin resistance was estimated by the Homeostasis Model Assessment of insulin resistance (HOMA-IR). The prevalence of obesity, abdominal obesity, and metabolic syndrome in the subjects with gallstones were higher than in those without. The prevalence of elevated HOMA (>75 percentile) in subjects with gallstones was significantly higher than in those without, and this association remained even after the obesity stratification was applied. In multiple logistic regression analyses, only age and HOMA proved to be independent predictors of gallstones. Insulin resistance was positively associated with gallstones in non-diabetic Korean men, and this occurred regardless of obesity. Gallstones appear to be a marker for insulin resistance, even in non-diabetic, nonobese men.

Combination of endoprostheses and oral ursodeoxycholic acid or placebo in the treatment of difficult to extract common bile duct stones

BACKGROUND

When common bile duct (CBD) stones cannot be removed after conventional endoscopic techniques or mechanical lithotripsy, biliary stenting serves for further planned endoscopic attempt of stone removal or operation. The aim of our study was to investigate the effect of ursodeoxycholic acid (UDCA) or placebo plus endoprostheses on stones' fragmentation or size.

METHODS

Forty-one patients with difficult to extract CBD stones were prospectively studied. They were randomised to receive either a 10 Fr straight plastic stent and oral 750 mg UDCA (group A, 21 patients) or placebo (group B, 20 patients) daily for 6 months.

RESULTS

A total clearance of CBD was achieved in 16 patients (76.9%) of group A and 15 patients (75%) of group B. The stones remained unchanged in size in five patients (23.8%) of group A and five patients (25%) of group B. In seven patients (33%) of group A and five patients (25%) of group B a repeated ERCP demonstrated fragmentation of CBD stones that were easily extracted. A reduction in stones' size was observed in 8 patients (38%) of group A (1.61 +/- 0.32 cm before treatment vs. 1.21 +/- 0.24 cm after treatment, p = 0.002) and 10 patients (50%) of group B (1.61 +/- 0.35 cm before vs. 1.24+/-0.22 cm after treatment, p = 0.001). There was no statistically significant difference on stone size reduction (p = 0.602) and fragmentation (p=0.558) between the two groups.

CONCLUSION

The results of this study suggest that UDCA does not seem to contribute to the reduction in stones' size or stones' fragmentation during the endoprosthetic procedure.

Prevalence of and risk factors for gallbladder polyps detected by ultrasonography among healthy Chinese: analysis of 34 669 cases

BACKGROUND AND AIM

Gallbladder (GB) polyps are tumor or tumor-like projections arising from GB mucosa. Although most polyps are benign, some early GB carcinomas present as polypoid lesions. The diagnosis of GB polyps is relatively easy by ultrasonography. Although numerous studies have investigated GB polyps, few studies have addressed the prevalence of and factors associated with GB polyps for specific ethnic populations. This study analyzes the prevalence and factors associated with GB polyps in a Chinese population who can afford a paid general checkup.

METHODS

The prevalence of and risk factors for GB polyps diagnosed by ultrasonography were retrospectively investigated in 34 669 Chinese patients who underwent a general checkup at Chang Gung Memorial Hospital (Taipei, Taiwan) between 2000 and 2003. Demographic, hemogram, serum biochemistry, hepatitis B surface antigen, hepatitis C antibody, and ultrasonography study data was available for all the patients. The correlations between the prevalence of GB polyps and age, sex, body height, body weight, body mass index, hemogram, serum biochemistry, and viral markers were examined for all the patients.

RESULTS

Excluding the patients who underwent cholecystectomy, the overall prevalence of GB polyps was 9.5% and highest for middle-aged males. The analyzed risk factors with increased odds ratios (OR) for the development of GB polyps were male sex (OR 0.646, P < 0.0005) and hepatitis B virus surface antigen positivity (OR 1.113, P < 0.0005). Other demographic characteristics and biochemical parameters, including body height, body weight, body mass index, lipid profile, chronic hepatitis C virus infection, and liver function did not correlate with the presence of GB polyps.

CONCLUSION

The prevalence of GB polyps among the Chinese in this study is higher than that reported for other populations. Chinese males and other patients with chronic hepatitis B viral infections have a high risk for developing GB polyps.

Defined indications for elective cholecystectomy for gallstone disease

BACKGROUND

This study examined symptomatology and quality of life following elective cholecystectomy for symptomatic gallstone disease with defined indications for surgery.

METHODS

In this prospective study of 200 consecutive patients (161 women; median age 46.5 (range 24-79) years), strict indications for elective cholecystectomy were stipulated. Digestive symptoms and quality of life were recorded with a self-administered questionnaire before and at 3 and 12 months after surgery.

RESULTS

Of 149 patients who experienced abdominal pain with typical location before surgery, 136 (91.3 per cent) reported total remission or reduced frequency of that type of pain 12 months later. Of 35 patients who reported atypical or multiple pain location before operation, 27 (77 per cent) experienced reduced frequency or disappearance of that type of pain. Frequency of pain episodes, atypical or multiple pain location, specific food intolerance and frequency of disturbing abdominal gas at baseline correlated positively with the frequency of abdominal pain episodes at 12 months after surgery. There was a tendency towards an inverse relation to age.

CONCLUSION

The frequency of persistent abdominal pain after elective cholecystectomy was low among patients with typical pain location before surgery. Atypical pain location, and frequent pain episodes before operation significantly reduced the chance of becoming pain-free.

Polymorphism of genes related to insulin sensitivity and the risk of biliary tract cancer and biliary stone: a population-based case-control study in Shanghai, China

Biliary tract cancer, encompassing tumors of the gallbladder, extrahepatic bile ducts and ampulla of Vater, is a rare but highly fatal malignancy. Obesity and gallstones, both related to insulin resistance, are linked to an elevated risk of biliary cancer. The peroxisome proliferator-activated receptors (PPARs) and the retinoid X receptors (RXRs), expressed in adipose tissue, play a key role in the regulation of obesity-related insulin sensitivity, thus genetic variants of these two receptor genes may be related to biliary cancer and stones. We examined the associations of seven single-nucleotide polymorphisms in the PPAR-γ, PPAR-δ, RXR-α, RXR-β and INS genes with biliary cancer and stones in a population-based case–control study in Shanghai, China. We included 237 gallbladder, 127 extrahepatic bile duct and 47 ampulla of Vater cancer cases, 895 stone cases and 786 population controls. Relative to individuals with the RXR-β C51T (rs2076310) CC genotype, those having the TT genotype had a 1.6-fold risk for bile duct cancer [odds ratio (OR) = 1.67; 95% confidence interval (CI) = 0.99–2.84], with a more pronounced association among men (OR = 2.30; 95% CI = 1.14–4.65; P interaction = 0.07). This marker was also associated with a higher risk of gallstones among subjects with a higher body mass index (BMI) (≥23 kg/m²) (OR = 1.80; 95% CI = 1.09–2.94), although the interaction with BMI was not statistically significant (P interaction = 0.28). No association was found between other variants and biliary cancers and stones. Results from this population-based study suggest that certain genetic variants involved in the regulation of obesity-related insulin sensitivity may increase susceptibility to bile duct cancer and gallstones.

Management of cholelithiasis in Italian children: A national multicenter study

AIM: To evaluate the management of Italian children with cholelithiasis observed at Pediatric and Surgical Departments linked to Italian Society of Pediatric Gastroenterology Hepatology and Nutrition.

METHODS: One-hundred-eighty children (90 males, median age at diagnosis 7.3 years; range, 0-18 years) with echographic evidence of cholelithiasis were enrolled in the study; the data were collected by an anonymous questionnaire sent to participating centers.

RESULTS: One hundred seventeen patients were treated with ursodeoxycholic acid; in 8 children dissolution of gallstones was observed, but the cholelithiasis recurred in 3 of them. Sixty-five percent of symptomatic children treated became asymptomatic. Sixty-four patients were treated with cholecystectomy and in only 2 cases a postoperative complication was reported. Thirty-four children received no treatment and were followed with clinical and echographic controls; in no case the development of complications was reported.

CONCLUSION: The therapeutic strategies were extremely heterogeneous. Ursodeoxycholic acid was ineffective in dissolution of gallstones but it had a positive effect on the symptoms. Laparoscopic cholecystectomy was confirmed to be an efficacy and safe treatment for pediatric gallstones.

Magnesium: does a mineral prevent gallstones?

Gallstone-related disorders are common and costly, but preventive measures are largely unexplored. Lifestyle risk factors include physical activity, obesity/overweight, and diet. Increasing consumption of magnesium appears to decrease the risk of symptomatic gallstones in men, although the underlying mechanisms remain unclear. Understanding the role of a healthy diet in gallstone-related diseases, including a diet high in magnesium, may lead to new preventive measures.

Insulin resistance and incident gallbladder disease in pregnancy

BACKGROUND & AIMS

Insulin resistance is associated with prevalent gallstones, but its effect on initial gallstone formation is not well-understood.

METHODS

We conducted a nested case-control study to examine whether insulin resistance is a risk factor for initial gallbladder sludge and stone formation during pregnancy. Cases were 205 women with new gallbladder sludge and stones during pregnancy and the early postpartum. Controls were 443 randomly selected women without sludge or stones during pregnancy. Gallbladder ultrasounds were obtained during each trimester and at 4-6 weeks post partum. Fasting serum glucose, lipids, and insulin were measured at 26-28 weeks gestation. Insulin resistance was measured by the homeostasis model. Logistic regression was used to identify independent risk factors for gallstone formation.

RESULTS

Insulin resistance was significantly greater in cases than in controls on univariate analysis (P < .001). Pre-pregnancy body mass index was strongly associated with gallstone formation on univariate analysis (P < .001), but this association was diminished after adjusting for insulin resistance (P = .01). On multivariate analysis, insulin resistance was significantly associated with gallstone formation (P = .004), even after adjustment for pre-pregnancy body mass index and other confounding factors including high-density lipoprotein cholesterol and physical activity. This association was strongest in women with pre-pregnancy body mass index <30 kg/m(2).

CONCLUSIONS

Insulin resistance is a risk factor for incident gallbladder sludge and stones during pregnancy, even after adjustment for body mass index. Insulin resistance might represent a causal link between obesity and overweight and gallstones.

HCV infection is a risk factor for gallstone disease in liver cirrhosis: an Italian epidemiological survey

We assessed the prevalence of gallbladder disease (i.e. gallstones plus cholecystectomy) among patients with liver disease and its association with the severity and aetiology of hepatic injury. Subjects, referred to 79 Italian hospitals, were enrolled in a 6-month period. The independent effect of the severity and aetiology of liver disease on gallstone disease prevalence was assessed by multiple logistic regression analysis. Overall, 4867 subjects tested anti-hepatitis C virus (HCV) positive alone, 839 were hepatitis B virus surface antigen (HBsAg) alone, and 652 had an excessive alcohol intake. The prevalence of gallstone disease was 23.3% in anti-HCV-positive patients, 12.4% in HBsAg positive and 24.2% in subjects reporting excessive alcohol intake, respectively. Gallstone disease prevalence increased by age in each aetiological category. The proportion of patients with gallstone disease who had a cholecystectomy was the highest in HCV+ subjects. After adjusting for the confounding effect of age and body mass index, compared with patients with less severe liver disease, subjects with HCV-related cirrhosis, but not those with alcohol-related cirrhosis, were more likely to have gallstone disease. Subjects with HCV-related cirrhosis (OR 2.13, 95% CI: 1.38-3.26) were more likely to have gallstone disease when compared with those with HBV-related cirrhosis. HCV infection is a risk factor for gallstone disease. In Italy, the high prevalence of HCV infection among cirrhotic patients has important implications, as cholecystectomy in these subjects is associated with high risk of morbidity and mortality.

Genetic evidence that apolipoprotein E4 is not a relevant susceptibility factor for cholelithiasis in two high-risk populations

Apolipoprotein E (apoE) isoforms are genetic determinants of interindividual variations in lipid metabolism. To assess whether apoE is a genetic risk factor for cholesterol gallstone disease (GD), we analyzed apoE variants in populations from Chile and Germany, two countries with very high prevalence rates of this disease. ApoE genotypes were determined in Chilean gallstone patients (n = 117) and control subjects (n = 122) as well as in German gallstone patients (n = 184) and matched controls (n = 184). In addition, we studied apoE variants in subgroups of Chilean patients with strong differences in their susceptibility to acquire gallstones: 50 elderly subjects without gallstones in spite of well-known risk factors for this disease (gallstone-resistant) and 32 young individuals with gallstones but without risk factors (gallstone-susceptible). Furthermore, correlation analysis of apoE genotypes with cholesterol crystal formation times, biliary cholesterol saturation index (CSI), and gallstone cholesterol contents was performed in 81 cholecystectomized patients. In this study analyzing the largest sample set available, apoE4 genotype was not associated with an increased frequency of GD in either population. Moreover, in the Chilean population after adjusting for risk factors such as gender, age, body mass index, serum lipids, and glucose, the odds ratio for the association of the apoE4 allele and GD was significantly (P < 0.05) <1. Also, genotypes were not correlated with cholesterol crystal formation time, CSI, or gallstone cholesterol content. In contrast to previous smaller studies, apoE polymorphisms were not associated with susceptibility to cholesterol GD in high-risk populations.

Incidence and risk factors for gallstones in patients with inflammatory bowel disease: a large case-control study

The risk for gallstones (GD) in inflammatory bowel diseases and the factors responsible for this complication have not been well established. We studied the incidence of GD in a cohort of Crohn's disease (CD) and ulcerative colitis (UC) patients and investigated the related risk factors. A case-controlled study was carried out. The study population included 634 inflammatory bowel disease (IBD) patients (429 CD, 205 UC) and 634 age-matched, sex-matched, and body mass index (BMI)-matched controls free of GD at enrollment, who were followed for a mean of 7.2 years (range, 5-11 years). The incidence of GD was calculated by dividing the number of events per person-years of follow-up. Multivariate analysis was used to discriminate among the impact of different variables on the risk of developing GD. The incidence rates of GD were 14.35/1,000 persons/year in CD as compared with 7.75 in matched controls (P=0.012) and 7.48/1000 persons/year in UC patients as compared with 6.06 in matched-controls (P=0.38). Ileo-colonic CD location (OR, 2.14), disease duration>15 years (OR, 4.26), >3 clinical recurrences (OR, 8.07), ileal resection>30 cm (OR, 7.03), >3 hospitalizations (OR, 20.7), multiple TPN treatments (OR, 8.07), and long hospital stay (OR, 24.8) were significantly related to GD in CD patients.

CONCLUSION

Only CD patients have a significantly higher risk of developing GD than well-matched hospital controls. Site of disease at diagnosis, lifetime surgery, extent of ileal resections, number of clinical recurrences, TPN, and the frequency and duration of hospitalizations are independently associated with GD.

Trends in the utilization of endoscopic retrograde cholangiopancreatography (ERCP) in the United States

OBJECTIVES

To evaluate nationwide trends in the utilization of endoscopic retrograde cholangiopancreatography (ERCP) in relation to the advent of noninvasive methods of visualizing the biliary and pancreatic tree.

METHODS

Retrospective cohort study. The Nationwide Inpatient Sample (NIS) database was used to calculate the age-adjusted rate for ERCPs performed from 1988 to 2002. The State Ambulatory Surgery Database (SASD) was used to evaluate trends in outpatient ERCPs from 1997 to 2003. Linear Poisson multivariate regression model was used to control for variations in age, gender, and ethnicity among the overall patient population.

RESULTS

The NIS database contained 402,343 patients who had an ERCP performed from 1988 to 2002. The mean age for these patients was 60.21 +/- 19.56 yr old. From 1988 to 1996; the age-adjusted rate for ERCPs increased by nearly threefold, from 25.66 per 100,000 in 1988 to 74.95 in 1996. The rate of 74.95 in 1996 declined to a rate of 59.70 by the year 2002. The rates of diagnostic ERCPs in men and women were 26.76 and 31.58 per 100,000 in 1988-1990, respectively. This rate then increased to 35.66 and 43.18 per 100,000 in 1994-1996, which then declined to 29.01 and 29.06 in 2000-2002. The age-adjusted rate for therapeutic ERCPs in men and women was 13.74 and 15.61 per 100,000 in 1988-1990, respectively, which continued to increase throughout the time span to 38.76 and 43.75 in 2000-2002. The SASD revealed a continual decline in outpatient ERCPs from 25.45 per 100,000 in 1997 down to 16.17 per 100,000 in the year 2003.

CONCLUSION

The utilization of ERCP dramatically increased from 1988 to 1996; however, since the advent of noninvasive diagnostic techniques such as endoscopic ultrasound (EUS) and magnetic resonance cholangiopancreatography (MRCP), there has been a steady decline in the utilization of diagnostic ERCPs from 1996 to 2002.

Acute Cholecystitis Complicating Cardiac Surgery: Case Series Involving More Than 16,000 Patients

BACKGROUND

Acute cholecystitis after cardiac surgery is rare but carries a high mortality. Its management remains controversial.

METHODS

We reviewed all cases of calculous cholecystitis (CC) and acalculous cholecystitis (ACC) encountered at our institution over the past 11 years. Data collection included preoperative variables, details of performed procedures, postoperative course, and outcome.

RESULTS

The overall incidence was 0.03% for CC and 0.08% for ACC (5 and 13 of 16,576 patients, respectively). Patients in the ACC group appeared to be sicker patients whereas most patients in the CC group had an uncomplicated recovery from cardiac surgery. The diagnosis was straightforward with typical presentation and ultrasonographic findings in the CC group. In the ACC group, the presentation was less specific, and although useful as diagnostic tool, ultrasonography findings were not as consistent as in the CC group. In the CC group, 3 patients underwent surgery, and 2 patients were treated conservatively. One patient died of cardiac causes after uncomplicated cholecystectomy. In the ACC group, 7 patients were treated medically and 6 patients underwent surgery. The overall mortality was 23% (3 patients). All deaths occurred in patients treated surgically.

CONCLUSIONS

Given the low incidence of CC, we do not recommend preoperative screening or intervention for cholelithiasis. Treatment should be according to established guidelines. Patients with ACC, without overt peritonitis, should initially be treated conservatively with appropriate antibiotics. However, failure of significant improvement within 48 hours or a worsening clinical picture should lead to surgical intervention.

Cholecystectomy and endometrial cancer: a marker of long-term elevated estrogen exposure?

Excess hormones, both endogenous and exogenous, are implicated in the etiology of endometrial cancer. We considered whether having had gallstones or a cholecystectomy (surgery to remove the gallbladder), which are more common in women who are obese and who use exogenous hormones, might be a marker for high lifetime levels of estrogen. We conducted a population-based study of endometrial cancer cases and community controls in women aged 40-79 years. Participants completed an interviewer-administered questionnaire that elicited exposures prior to diagnosis or reference date, including history of gallstones and cholecystectomy, as well as reproductive history, lifetime body mass, smoking, postmenopausal hormone (PMH) use, and other risk factors. Compared to controls, cholecystectomy was associated with a 50% increased risk of developing endometrial cancer (odds ratio = 1.5 [1.1-2.0]). The relationship appeared to depend upon PMH user status; the association was observed only among never hormone users. Body mass index did not appear to modify this relationship. Having a diagnosis of gallstones was also associated with endometrial cancer, although to a lesser magnitude. Although other etiologic factors may play a role in the relation between cholecystectomy and endometrial cancer, the current analysis suggests that this association is attributable, at least in part, to the sharing of hormonal risk factors.

Need for criteria for the diagnosis and severity assessment of acute cholangitis and cholecystitis: Tokyo Guidelines

The Tokyo Guidelines formulate clinical guidance for healthcare providers regarding the diagnosis, severity assessment, and treatment of acute cholangitis and acute cholecystitis. The Guidelines were developed through a comprehensive literature search and selection of evidence. Recommendations were based on the strength and quality of evidence. Expert consensus opinion was used to enhance or formulate important areas where data were insufficient. A working group, composed of gastroenterologists and surgeons with expertise in biliary tract surgery, supplemented with physicians in critical care medicine, epidemiology, and laboratory medicine, was selected to formulate draft guidelines. Several other groups (including members of the Japanese Society for Abdominal Emergency Medicine, the Japan Biliary Association, and the Japanese Society of Hepato-Biliary-Pancreatic Surgery) have reviewed and revised the draft guidelines. To build a global consensus on the management of acute biliary infection, an international expert panel, representing experts in this area, was established. Between April 1 and 2, 2006, an International Consensus Meeting on acute biliary infections was held in Tokyo. A consensus was determined based on best available scientific evidence and discussion by the panel of experts. This report describes the highlights of the Tokyo International Consensus Meeting in 2006. Some important areas focused on at the meeting include proposals for internationally accepted diagnostic criteria and severity assessment for both clinical and research purposes.

Gender and gallstone disease

Gallstone disease is a common disorder all over the world. In the Western societies about 80 % of the gallstones are composed primarily of cholesterol. Several risk factors for gallstone formation have been identified. One of the most important risk factors is female gender. Rates of gallstones are two to three times higher among women than men. But this is primarily a phenomenon of the childbearing age. Pregnancy is also a major risk factor for gallstone formation. The risk is related to the number of pregnancies. Sex hormones are most likely to be responsible for the increased risk. Estrogen increases biliary cholesterol secretion causing cholesterol supersaturation of bile. Thus, hormone replacement therapy in postmenopausal women and oral contraceptives have also been described to be associated with an increased risk for gallstone disease. However, the effect of estrogen is dose-dependent and new oral contraceptives with a low estrogen dose do not seem to increase the rate of gallstone formation. The present article focuses on the mentioned risk factors associated with female sex hormones.

Prevalence and risk factors of gallstone disease in an adult population of Taiwan: an epidemiological survey

BACKGROUND AND AIMS

The aim of this study was to determine the prevalence and risk factors of gallstone disease (GSD) in an adult population of Taiwan through a population-based screening study.

METHODS

A cross-sectional community study in a rural village of Taiwan was conducted in 3333 Chinese adults (aged > or = 18 years) undergoing ultrasonography. A questionnaire on personal history was completed to ascertain whether the removed gallbladder contained stones in all cholecystectomized subjects, the dietary habits (vegetarian/non-vegetarian diet), the history of GSD in the participant's first-degree relatives, the history of gastrointestinal surgery (vagotomy, gastrectomy for peptic ulcer disease, or ileal resection), parity, and use of oral contraceptives. The demographic characteristics and biochemical parameters were recorded.

RESULTS

The overall prevalence of GSD was 5.0% (4.6% in men, 5.4% in women) with no significant sex differences (men/women: odds ratio [OR] 0.71, 95% confidence interval [CI] 0.50-1.01, P = 0.058). Logistic regression analysis showed that increasing age (men: 40-64 years, OR 7.38, 95% CI 2.59-21.01, P < 0.001 and > or = 65 years, OR 14.16, 95% CI 4.84-41.47, P < 0.001; women: 40-64 years, OR 4.08, 95% CI 1.90-8.75, P < 0.001 and > or = 65 years, OR 6.78, 95% CI 2.97-15.46, P < 0.001) and the presence of fatty liver evidenced by ultrasonography (men: OR 2.24, 95% CI 1.32-3.80, P = 0.003; women: OR 2.13, 95% CI 1.33-3.42, P = 0.002) were risk factors for GSD. Additionally, fasting plasma glucose > or = 126 mg/dL (OR 2.11, 95% CI 1.16-3.83, P = 0.014), history of GSD in the first-degree relatives (OR 7.47, 95% CI 2.22-25.12, P = 0.001), and use of oral contraceptives (OR 10.71, 95% CI 3.06-37.49, P < 0.001) were risk factors for GSD in women, but fasting plasma glucose > or = 126 mg/dL was only correlated to GSD without controlling for other confounding factors in men. Other demographic characteristics and biochemical parameters, such as high body mass index (> or = 25 kg/m2), increased parity, hypercholesterolemia, hypertriglyceridemia, hyperuricemia, hepatitis C infection and cirrhosis, did not exhibit any correlation to GSD in logistic regression analysis, although they appeared to be related to GSD in women in univariate analysis.

CONCLUSIONS

Age and fatty liver in both sexes were found to be risk factors for GSD in the study population. The finding of a correlation between fatty liver and GSD is an important addition to the literature concerning the risk factors of GSD. Diabetes mellitus, history of GSD in the first-degree relatives, and use of oral contraceptives were also risk factors for GSD in women.

Risk factors for gallstone-related hospitalization during pregnancy and the postpartum

OBJECTIVES

Gallbladder disease is a leading nonobstetrical cause for hospitalization in the first year postpartum. The aim of this study was to define the incidence and risk factors for postpartum hospitalization as a result of gallstone-related disease.

METHODS

We identified 6,670 women with discharge diagnoses related to biliary disease from linked birth certificate and hospital discharge databases for Washington State from 1987 through 2001. Cases were women with gallstone-related diagnoses at delivery or as primary diagnosis in the postpartum. Four controls who were within 1 yr postpartum were randomly selected for each case and matched for year of delivery. From the birth certificates, we obtained data about patient demographics, reproductive history, and pregnancy-related risk factors. In a retrospective case-control study, we developed multiple logistic regression models to identify independent risk factors for hospitalization.

RESULTS

We identified 6,211 women as cases (0.5% of all births) during the study period. The median time to hospitalization was 95 days (interquartile range 46-191 days), with a median length of stay of 3 days. Seventy-six percent were diagnosed with uncomplicated cholelithiasis, 16% with pancreatitis, 9% with acute cholecystitis, and 8% with cholangitis. Seventy-three percent of hospitalized women underwent cholecystectomy, and 5% underwent endoscopic retrograde cholangiopancreatography (ERCP). On multivariate analysis, independent risk factors for hospitalization included maternal race, age, being overweight or obese prepregnancy, pregnancy weight gain, and estimated gestational age.

CONCLUSIONS

Hospitalization for gallstone-related disease is common in the first year postpartum, most commonly for uncomplicated cholelithiasis. Risk factors for hospitalization include prepregnancy body mass index, race, Hispanic ethnicity, and maternal age.

Insulin resistance causes human gallbladder dysmotility

Obesity, diabetes, and hyperlipidemia are known risk factors for the development of gallstones. A growing body of animal and human data has correlated insulin resistance with organ dysfunction. The relationship among obesity, diabetes, hyperlipidemia, and abnormal gallbladder motility remains unclear. Therefore, we designed a study to investigate the association among obesity, insulin resistance, hyperlipidemia, and gallbladder dysmotility. One hundred ninety-two healthy adult nondiabetic volunteers were studied. Gallbladder ultrasounds were performed before and after a standardized fatty meal. A gallbladder ejection fraction (EF) was calculated, and an EF of < 25% was considered abnormal. Serum was analyzed for cholesterol, triglycerides, cholecystokinin, leptin, glucose, and insulin. The homeostasis assessment model (HOMA) was used to determine insulin resistance. The volunteers had a mean age of 38 years (range, 18-77), and 55% were female. Thirty subjects (15%) had gallstones and were excluded from the study. Thirty subjects (19%) had abnormal gallbladder motility (EF < 25%). In lean subjects (n = 96) fasting glucose was significantly increased in the 16 subjects with gallbladder EF < 25% versus the 80 subjects with gallbladder EF > 25% (109 +/- 20 mg/dl versus 78 +/- 2 mg/dl, P < 0.05). Similarly, the HOMA index was significantly greater in subjects with gallbladder EF < 25% versus gallbladder EF >25% (3.3 +/- 1.2 versus 2.0 +/- 0.2, P < 0.05). In obese subjects (n = 66), fasting glucose, insulin, and insulin resistance were not associated with a gallbladder EF < 25%. These data suggest that in lean, nondiabetic volunteers without gallstones, gallbladder dysmotility is associated with an elevated fasting glucose as well as a high index of insulin resistance. We conclude that insulin resistance alone may be responsible for gallbladder dysmotility that may result in acalculous cholecystitis or gallstone formation.

Risk factors associated with gallstone and biliary sludge formation during pregnancy

AIM

To define the risk factors in gallstone and sludge formation, and to investigate the incidence of gallstone and biliary sludge formation during pregnancy in a group of healthy pregnant women.

METHODS

Sixty-nine healthy pregnant women in early gestation and 28 nulliparous healthy controls were enrolled. Gallbladder volumes, gallbladder ejection fraction (GBEF), serum triglyceride and cholesterol levels were determined in both groups. In the pregnant group, repeated measurements were performed immediately after delivery and compared with initial levels. Risk factors, which are associated with gallstone and biliary sludge development during pregnancy, were determined by linear regression analysis.

RESULTS

No statistically significant difference was observed in the assessed parameters of pregnant women in early gestation and controls (both P > 0.05). In the pregnant group, gallstone and biliary sludge development during pregnancy were detected in 6.3% and 10.9% of cases, respectively. The detected parameters were significantly higher early after delivery than in early gestation, while GBEF was lower (both P < 0.001). Lower GBEF was the most significant factor (P < 0.001) associated with gallstone and sludge formation during pregnancy, while multiple childbirths was the other (P = 0.04).

CONCLUSION

Decrease in GBEF is the most significant risk factor for newly developed gallstone and sludge in pregnant women, while multiple childbirths is the other but less important risk factor.

Evaluation of the biliary tract in patients with functional biliary symptoms

The aim of this paper was to describe functional biliary syndromes and methods for evaluation of the biliary tract in these patients. Functional biliary symptoms can be defined as biliary symptoms without demonstrable organic substrate. Two main syndromes exist: Gallbladder dysfunction and sphincter of Oddi dysfunction. The most important investigative tools are cholescintigraphy and endoscopic sphincter of Oddi manometry. In gallbladder dysfunction a scintigraphic gallbladder ejection fraction below 35% can select patients who will benefit from cholecystectomy. Endoscopic sphincter of Oddi manometry is considered the gold standard in sphincter of Oddi dysfunction but recent development in scintigraphic methods is about to change this. Thus, calculation of hilum-to-duodenum transit time and duodenal appearance time on cholescintigraphy have proven useful in these patients. In conclusion, ambient methods can diagnose functional biliary syndromes. However, there are still a number of issues where further knowledge is needed. Probably the next step forward will be in the area of sensory testing and impedance planimetric methods.

Functional gallbladder and sphincter of oddi disorders

The functional disorder of the gallbladder (GB) is a motility disorder caused initially either by metabolic abnormalities or by a primary motility alteration. The functional disorders of the sphincter of Oddi (SO) encompass motor abnormalities of either the biliary or the pancreatic SO. Dysfunction of the GB and/or biliary SO produce similar patterns of pain. The pain caused by a dysfunction of the pancreatic SO can be similar to that of acute pancreatitis. The symptom-based diagnostic criteria of motility dysfunction of the GB and biliary SO are episodes of moderate to severe steady pain located in the epigastrium and right upper abdominal quadrant that last at least 30 minutes. GB motility disorder is suspected after gallstones and other structural abnormalities have been excluded. This diagnosis should then be confirmed by a decreased GB ejection fraction induced by cholecystokinin at cholescintigraphy and after disappearance of the recurrent biliary pain after cholecystectomy. Symptoms of biliary SO dysfunction may be accompanied by features of transient biliary obstruction, and those of pancreatic SO dysfunction are associated with elevation of pancreatic enzymes and even pancreatitis. Biliary-type SO dysfunction is more frequently recognized in postcholecystectomy patients. SO manometry is valuable to select patients with sphincter dysfunction; however, because of the high incidence of complications, these patients should be referred to an expert unit for such assessment. Thus invasive tests should be performed only in the presence of compelling clinical evidence and after noninvasive testing has yielded negative findings. The committee recommends that division of the biliary or pancreatic sphincters only be considered when the patient has severe symptoms, meets the required criteria, and other diagnoses are excluded.

Is there a link between oestrogen therapy and gallbladder disease?

Cholelithiasis is the most common form of benign gallbladder disease that results in major heath expenditure. Female sex hormones are causally related to cholesterol gallstone disease, which are more common in women than in men. The risk of development of cholelithiasis is further enhanced by the use of exogenous female sex hormones and by pregnancy. Oestrogens are used in oral contraceptives and in hormone replacement therapy (HRT). Oral contraceptives do not pose a greater risk for gallbladder disease. The findings from two randomised, controlled trials, the Heart and Oestrogen/Progestin Replacement Study and the Women's Health Initiative postmenopausal hormone trial, unequivocally confirm that oral oestrogen use in postmenopausal women is causally associated with gallbladder disease, and the magnitude of the effect is not influenced greatly by the presence or absence of progestins. A cautious approach should be observed when prescribing HRT. Women must be informed about the effect of oestrogen use on increased risk of benign gallbladder disease. HRT should be used in the lowest possible dose for the shortest possible time. Women harbouring asymptomatic gallstones should not receive oestrogens because of the possibility of developing cholecystitis.

Gallstone disease: Epidemiology, pathogenesis, and classification of biliary stones (common bile duct and intrahepatic)

Gallstones are common in Western countries and Japan. Most gallstones are found in the gallbladder, but they sometimes pass through the cystic duct into extrahepatic and/or intrahepatic bile ducts to become bile-duct stones, causing conditions known as choledocholithiasis and hepatolithiasis. Some 10-15% of gallstone patients concomitantly suffer from bile-duct stones. Bile-duct stones can also be formed in the absence of gallbladder stones, and such primary bile-duct stones are more common in East Asian countries than in the Western world. Thus pathogenesis of primary and secondary bile-duct stones is unlikely to be similar. Furthermore, the gallbladder stones are primarily cholesterol or black-pigment stones, whereas most bile-duct stones are brown-pigment stones (calcium bilirubin stones). Thus, epidemiology, pathogenesis and classification of biliary stones are very likely to differ according to stone location (intrahepatic and/or extrahepatic bile duct).

Gallstone disease: Symptoms and diagnosis of gallbladder stones

The clinical aspects and the diagnostic features of gallstone disease are described. The natural history of silent gallstones is overviewed, and the risk of developing symptoms and complications is also discussed. The importance of colicky pain as a specific gallstone symptom is highlighted, and the role of both laboratory tests and diagnostic investigations for differential diagnosis is discussed. Finally, we describe the diagnostic features of gallbladder stone disease, including indications, sensitivity, specificity, and limitations of different test investigations under special circumstances.

Gallstone disease: Primary and secondary prevention

Several risk factors for cholesterol gallstone formation in the general population have been identified. There is a strongly increased risk of gallstone disease during prolonged fasting, rapid weight loss, total parenteral nutrition, and somatostatin(-analogue) treatment. The annual risk of biliary colic and gallstone complications in asymptomatic gallstone carriers has been investigated sparsely. In asymptomatic and symptomatic gallstone carriers, treatment with the hydrophilic bile salt ursodeoxycholic acid (UDCA) has been claimed to reduce the risk of biliary colic and gallstone complications such as acute cholecystitis and acute pancreatitis. Also, prophylactic cholecystectomy could be beneficial in certain subgroups of asymptomatic gallstone carriers. However, randomized, double-blind, placebo-controlled trials are lacking. In this review, strategies for the prevention of gallstone formation in the general population and in high-risk conditions are dealt with. Also, strategies for the prevention of biliary colic and gallstone complications in asymptomatic and symptomatic gallstone carriers are discussed.

Gallstone disease: Epidemiology of gallbladder stone disease

Gallstone disease is common: >700,000 cholecystectomies and costs of approximately 6.5 billion dollars annually in the U.S. The burden of disease is epidemic in American Indians (60-70%); a corresponding decrease occurs in Hispanics of mixed Indian origin. Ten to fifteen per cent of white adults in developed countries harbour gallstones. Frequency is further reduced in Black Americans, East Asia and sub-Saharan Africa. In developed countries, cholesterol gallstones predominate; 15% are black pigment. East Asians develop brown pigment stones in bile ducts, associated with biliary infection or parasites, or in intrahepatic ducts (hepatolithiasis). Certain risk factors for gallstones are immutable: female gender, increasing age and ethnicity/family (genetic traits). Others are modifiable: obesity, the metabolic syndrome, rapid weight loss, certain diseases (cirrhosis, Crohn's disease) and gallbladder stasis (from spinal cord injury or drugs like somatostatin). The only established dietary risk is a high caloric intake. Protective factors include diets containing fibre, vegetable protein, nuts, calcium, vitamin C, coffee and alcohol, plus physical activity.

Pregnancy is not a risk factor for gallstone disease: Results of a randomly selected population sample

AIM: To investigate the prevalence, risk factors, and selection of the study population for cholecystolithiasis in an urban population in Germany, in relation to our own findings and to the results in the international literature.

METHODS: A total of 2 147 persons (1 111 females, age 42.8 ± 12.7 years; 1 036 males, age 42.3 ± 13.1 years) participating in an investigation on the prevalence of Echinococcus multilocularis were studied for risk factors and prevalence of gallbladder stone disease. Risk factors were assessed by means of a standardized interview and calculation of body mass index (BMI). A diagnostic ultrasound examination of the gallbladder was performed. Data were analyzed by multiple logistic regression, using the SAS statistical software package.

RESULTS: Gallbladder stones were detected in 171 study participants (8.0%, n = 2 147). Risk factors for the development of gallbladder stone disease included age, sex, BMI, and positive family history. In a separate analysis of female study participants, pregnancy (yes/no) and number of pregnancies did not exert any influence.

CONCLUSION: Findings of the present study confirm that age, female sex, BMI, and positive family history are risk factors for the development of gallbladder stone disease. Pregnancy and the number of pregnancies, however, could not be shown to be risk factors. There seem to be no differences in the respective prevalence for gallbladder stone disease in urban and rural populations.

Prevalence of gallstone disease in first-degree relatives of patients with cholelithiasis

AIM: To evaluate the influence of familiality on the prevalence of gallstone disease (GD) in Italy.

METHODS: Families of 79 subjects with gallstones (cases) and of 79 subjects without gallstones (controls) were investigated for the presence of gallstones by ultrasonography. Index cases and index controls were matched for age, sex, and operative unit. Sixty-three and sixty-two husbands and wives of index cases and index controls, respectively, were also studied.

RESULTS: Overall,the prevalence of GD was significantly higher ( χ²=14.52, P<0.001) in the 202 first-degree relatives of subjects with gallstones than that in the 201 first-degree relatives of subjects without gallstones (28.6% vs 12.4%, relative risk (RR) 1.80, 95% confidence interval (CI) 1.29-2.63). In particular, prevalence of GD was significantly higher in mothers, fathers, and sisters of index cases than that in the respective family members of index controls. The highest RR was observed in mothers (RR=2.35, 95%CI 1.38-4.3). Prevalence of GD was not obviously different in brothers and also in husbands and wives of index cases and index controls. Family members of index cases did not differ from family members of control cases with respect to the most important risk factors for gallstones (age, diabetes, BMI, and number of pregnancies) with an exception of a higher prevalence of diabetes in fathers of index controls than in fathers of index cases.

CONCLUSION: This study confirms that familiality plays a very important role in the pathogenesis of gallstones.