Effects of estrogen upon bile: implications with respect to gallstone formation

Breastfeeding in Prevention of Postpartum Acute Pancreatitis

BACKGROUND

Acute pancreatitis (AP) caused by gallstones has an increased rate of incidence in young women in the 2 years postpartum. Middle-aged women with longer periods of breastfeeding have less hospitalization for gallbladder disease.

AIM

To investigate whether breastfeeding or other variables may be associated with AP.

METHODS

We conducted a population-based case-control study among all Sicilian women of childbearing age, and we identified all women who delivered (2013-2016) and had AP within 2 years postpartum. We reviewed their medical records, and for each case we matched four women of the same age (± 5 years), without AP. Univariate and multivariate logistic regression was used to estimate the odds ratios (OR) with their confidence intervals (CI) to assess associations between AP and clinical determinants.

RESULTS

In the 74 women with AP and 298 controls at univariate analysis, > 6 months oral contraception history (p < 0.01; OR 3.30; 95% CI 1.33-8.16), previous biliary disease (p < 0.001; OR 5.90; 95% CI 1.98-17.57) and smoking (p = 0.035; OR 2.04; 95% CI 1.04-4.0) were predictors of AP; amenorrhea ≥ 3 months (p < 0.001; OR 0.34; 95% CI 0.19-0.59) and breastfeeding ≥ 3 months (p < 0.001; OR 0.07; 95% CI 0.03-0.14) were protective. At multivariate analysis, previous biliary disease (p = 0.011; OR 5.49; 95% CI 1.48-20.38) and breastfeeding ≥ 3 months (p < 0.001; OR 0.06; CI 95% 0.03-0.14) were associated with AP.

CONCLUSIONS

Women who breastfeed for at least 3 months and do not have a history of biliary disorders have reduced risk of developing AP in the 2 years after delivery.

Acute Pancreatitis During and After Pregnancy: Incidence, Risk Factors, and Prognosis

BACKGROUND

Acute pancreatitis may complicate pregnancy and both are associated with gallstones, but its incidence is not well known.

AIMS

To validate hospital discharge records in diagnosing acute pancreatitis and gallstones and to evaluate acute pancreatitis incidence in non pregnant, pregnant and after delivery using hospital discharge records METHODS: We identified all hospital discharge records of hospitalized Sicilian women of childbearing age (2011-2016). We determined agreement between 300 hospital discharge records and hospital records in diagnosing acute pancreatitis and gallstones. Acute pancreatitis incidence, prognosis, and their relationship with age and gallstones were calculated in the three groups using hospital discharge records.

RESULTS

There was 92% and 88% agreement in diagnosing acute pancreatitis and gallstones between hospital discharge and hospital records. In non pregnant, 1,564 of 7,236,863 women-years (21.61/100,000 person-years) developed acute pancreatitis. During pregnancy, 34 of 226,492 women-years developed acute pancreatitis (20.02/100,000 person-years). Postpartum acute pancreatitis incidence was higher than non pregnant, only in the first 2 years with the peak in the first semester (95.4/100,000 person-years). The increased incidence of postpartum acute pancreatitis was associated with gallstones in youngest women (gallstones acute pancreatitis in women below 20 years old versus non pregnant: rate ratios 16.61; 95% CI 8.40-32.87).

CONCLUSIONS

Agreement in acute pancreatitis and gallstones diagnosis between hospital discharge and hospital records was accurate. Acute pancreatitis incidence was increased only in the first 2 years after delivery in young women with gallstones.

Activation of Estrogen Receptor G Protein-Coupled Receptor 30 Enhances Cholesterol Cholelithogenesis in Female Mice

BACKGROUND AND AIMS

Estrogen is an important risk factor for cholesterol gallstone disease because women are twice as likely as men to form gallstones. The classical estrogen receptor α (ERα), but not ERβ, in the liver plays a critical role in the formation of estrogen-induced gallstones in female mice. The molecular mechanisms underlying the lithogenic effect of estrogen on gallstone formation have become more complicated with the identification of G protein-coupled receptor 30 (GPR30), an estrogen receptor.

APPROACH AND RESULTS

We investigated the biliary and gallstone phenotypes in ovariectomized female GPR30^-/- , ERα^-/- , and wild-type mice injected intramuscularly with the potent GPR30-selective agonist G-1 at 0 or 1 μg/day and fed a lithogenic diet for 8 weeks. The activation of GPR30 by G-1 enhanced cholelithogenesis by suppressing expression of cholesterol 7α-hydroxylase, the rate-limiting enzyme for the classical pathway of bile salt synthesis. These metabolic abnormalities led to an increase in biliary cholesterol concentrations in company with hepatic hyposecretion of biliary bile salts, thereby inducing cholesterol-supersaturated gallbladder bile and accelerating cholesterol crystallization. G-1 also impairs gallbladder emptying, leading to sluggish gallbladder motility and promoting the development of biliary sludge in the early stage of gallstone formation. The prevalence rates of gallstones were 80% in wild-type and ERα^-/- mice treated with G-1 compared to 10% in wild-type mice receiving no G-1. However, no gallstones were formed in GPR30^-/- mice treated with G-1.

CONCLUSIONS

GPR30 produces additional lithogenic actions, working independently of ERα, to increase susceptible to gallstone formation in female mice; both GPR30 and ERα are potential therapeutic targets for cholesterol gallstone disease, particularly in women and patients exposed to high levels of estrogen.

Sexual dimorphism of cardiometabolic dysfunction: Gut microbiome in the play?

BACKGROUND

Sex is one of the most powerful modifiers of disease development. Clear sexual dimorphism exists in cardiometabolic health susceptibility, likely due to differences in sex steroid hormones. Changes in the gut microbiome have been linked with the development of obesity, type 2 diabetes, and atherosclerosis; however, the impact of microbes in sex-biased cardiometabolic disorders remains unclear. The gut microbiome is critical for maintaining a normal estrous cycle, testosterone levels, and reproductive function. Gut microbes modulate the enterohepatic recirculation of estrogens and androgens, affecting local and systemic levels of sex steroid hormones. Gut bacteria can also generate androgens from glucocorticoids.

SCOPE OF REVIEW

This review summarizes current knowledge of the complex interplay between sexual dimorphism in cardiometabolic disease and the gut microbiome.

MAJOR CONCLUSIONS

Emerging evidence suggests the role of gut microbiome as a modifier of disease susceptibility due to sex; however, the impact on cardiometabolic disease in this complex interplay is lacking. Elucidating the role of gut microbiome on sex-biased susceptibility in cardiometabolic disease is of high relevance to public health given its high prevalence and significant financial burden.

The deletion of the estrogen receptor α gene reduces susceptibility to estrogen-induced cholesterol cholelithiasis in female mice

Compelling evidence has demonstrated that estrogen is a critical risk factor for gallstone formation and enhances cholesterol cholelithogenesis through the hepatic estrogen receptor α (ERα), but not ERβ. To study the lithogenic mechanisms of estrogen through ERα, we investigated whether the deletion of Erα protects against gallstone formation in ovariectomized (OVX) female mice fed a lithogenic diet and treated with 17β-estradiol (E2) at 0 or 6μg/day for 56days. Our results showed that the prevalence of gallstones was reduced from 100% in OVX ERα (+/+) mice to 30% in OVX ERα (-/-) mice in response to high doses of E2 and the lithogenic diet for 56days. Hepatic cholesterol secretion was significantly diminished in OVX ERα (-/-) mice compared to OVX ERα (+/+) mice even fed the lithogenic diet and treated with E2 for 56days. These alterations decreased bile lithogenicity by reducing cholesterol saturation index of gallbladder bile. Immunohistochemical studies revealed that ERα was expressed mainly in the gallbladder smooth muscle cells. High levels of E2 impaired gallbladder emptying function mostly through the ERα and cholecystokinin-1 receptor pathway, leading to gallbladder stasis in OVX ERα (+/+) mice. By contrast, gallbladder emptying function was greatly improved in OVX ERα (-/-) mice. This markedly retarded cholesterol crystallization and the growth and agglomeration of solid cholesterol crystals into microlithiasis and stones. In conclusion, the deletion of Erα reduces susceptibility to the formation of E2-induced gallstones by diminishing hepatic cholesterol secretion, desaturating gallbladder bile, and improving gallbladder contraction function in female mice.

Cholesterol cholelithiasis in pregnant women: pathogenesis, prevention and treatment

Epidemiological and clinical studies have found that gallstone prevalence is twice as high in women as in men at all ages in every population studied. Hormonal changes occurring during pregnancy put women at higher risk. The incidence rates of biliary sludge (a precursor to gallstones) and gallstones are up to 30 and 12%, respectively, during pregnancy and postpartum, and 1-3% of pregnant women undergo cholecystectomy due to clinical symptoms or complications within the first year postpartum. Increased estrogen levels during pregnancy induce significant metabolic changes in the hepatobiliary system, including the formation of cholesterol-supersaturated bile and sluggish gallbladder motility, two factors enhancing cholelithogenesis. The therapeutic approaches are conservative during pregnancy because of the controversial frequency of biliary disorders. In the majority of pregnant women, biliary sludge and gallstones tend to dissolve spontaneously after parturition. In some situations, however, the conditions persist and require costly therapeutic interventions. When necessary, invasive procedures such as laparoscopic cholecystectomy are relatively well tolerated, preferably during the second trimester of pregnancy or postpartum. Although laparoscopic operation is recommended for its safety, the use of drugs such as ursodeoxycholic acid (UDCA) and the novel lipid-lowering compound, ezetimibe would also be considered. In this paper, we systematically review the incidence and natural history of pregnancy-related biliary sludge and gallstone formation and carefully discuss the molecular mechanisms underlying the lithogenic effect of estrogen on gallstone formation during pregnancy. We also summarize recent progress in the necessary strategies recommended for the prevention and the treatment of gallstones in pregnant women.

Proximal shift of colorectal cancer along with aging

INTRODUCTION

Although several reports have documented the increased incidence of right-sided colorectal cancer (CRC) in the elderly, especially in women, the gender-specific, age-related changes in the characteristics of CRCs, especially related to the cancer localization, have not been fully investigated. This study evaluated the age-related changes in the clinicopathologic features of CRCs, according to the gender.

MATERIALS AND METHODS

A total of 1059 consecutive patients with CRCs who were admitted to the authors' surgical department between February 2005 and June 2012 were retrospectively reviewed. The patients were divided into male (n = 632) and female (n = 427) groups and then according to the age group, and the correlation between the age group and the other clinicopathologic features was analyzed by univariate and multivariate analysis.

RESULTS

The number of concomitant adenomas found was significantly increased along with increasing age in men, and the presence of concomitant adenoma was the only independent age-related factor of male CRC in the multivariate analysis (P = .0044). In contrast, in women, the location of the CRC progressively shifted to the right side (proximal colon) with increasing age, and the presence of right-sided CRC was the only independent factor of female CRC in the multivariate analysis (P < .0001).

CONCLUSION

There was a significant gender-specific difference in the age-related changes in the characteristics of CRC. Increasing the number of concomitant adenomas and the shift of CRC localization to the proximal colon were the gender-specific characteristics of male and female CRC, respectively.

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.

Severe acute pancreatitis and pregnancy

For most patients with pregnancy-associated pancreatitis there is little maternal survival threat and only occasionally are there foetal deaths. We describe 4 young women with pregnancy-associated severe acute pancreatitis who each had gallstones. Their ages were 17, 18, 20 and 24 years. Each was a tertiary referral to our unit in Glasgow and each pursued a life-threatening course with hospital stays ranging from 37 to 90 days. One patient required pancreatic necrosectomy for infected necrosis, another had percutaneous management of a pancreatic abscess and 2 had cystogastrostomy as treatment for pancreatic pseudocyst. All underwent early endoscopic sphincterotomy and later cholecystectomy. It is important to be aware that pregnancy-associated acute pancreatitis may be severe, posing a survival threat even in the youngest patients. Gallstones, as we reported almost 20 years ago, are the most common aetiological factor in such patients.

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: Microlithiasis and sludge

'Sludge' is the solid material which results from the slow settling of particles dispersed in a liquid medium. Biliary sludge in the gallbladder can be detected by transabdominal ultrasonography, and the typical echoes derive mainly from pigment precipitates mixed with cholesterol crystals. A portion of biliary sludge contains comparatively large particles (1-3 mm) called microliths, the formation of which is an obligatory intermediate step in the development of all types of gallstone. Microlithiasis and sludge in bile may cause colicky pain, cholecystitis, cholangitis, and acute pancreatitis, and are thus of clinical relevance. In these patients treatment follows the guidelines of symptomatic gallstone disease, and strategies include long-term application of ursodeoxycholic acid, endoscopic papillotomy, or preferably laparoscopic cholecystectomy.

Risk factors for cholelithiasis in pregnancy

This study was designed to examine the relationships of demographics, anthropometrics, prenatal physical activity, serum cholesterol, and nutrient intakes to symptomatic cholelithiasis (gallstone) occurrence in 128 northern plains pregnant women. Data collected at 14 and 26 weeks of pregnancy and 4 weeks after delivery, indicated 25.8% of the Native American and 8.3% of the Caucasian pregnant women experienced symptoms of cholelithiasis. Body mass indices (BMIs) were significantly higher in the pregnant women who experienced cholelithiasis than in those who did not have cholelithiasis, and prenatal physical activity was significantly lower in those same women. History of gallbladder disease (beta=.73; p=.001), BMI (beta=.33; p=.01), and prenatal physical activity (beta=-.20; p=.04) were predictive of increased occurrence of cholelithiasis during pregnancy.

Acute pancreatitis in the postpartum period: a population-based case-control study

OBJECTIVE

To determine relationships among pregnancy (during and postpartum), acute pancreatitis, and gallstones.

PATIENTS AND METHODS

In this retrospective population-based case-control study, we identified all 12- to 50-year-old Rochester, Minn, females diagnosed between 1976 and 1991 as having acute pancreatitis (cases). For each case, we matched 4 women of the same age (+/- 6 years) with no history of acute pancreatitis (controls). Acute pancreatitis was defined as associated with pregnancy if it occurred from 10 months prior to delivery to delivery and with the postpartum period if it occurred within 10 months of the date of delivery. Logistic regression was used to assess associations between pregnancy-related acute pancreatitis, age, gallstone occurrence, and alcohol use.

RESULTS

In a cohort of 61 women who developed acute pancreatitis and 244 controls, the relative risk for acute pancreatitis associated with pregnancy was 1.43 (95% confidence interval, 0.61-3.40). All 10 cases of acute pancreatitis associated with pregnancy occurred in the postpartum period. Gallstones were present in 6 of them compared with 13 of 51 women with non-pregnancy-related acute pancreatitis (P < .05). Women with postpartum-related pancreatitis were younger than those with non-pregnancy-related pancreatitis (mean, 28 vs 36 years; P < .05). Alcohol was not associated with pregnancy-related pancreatitis.

CONCLUSIONS

Acute pancreatitis during the postpartum period is not directly related to pregnancy but is associated with gallstones and occurs in younger women.

The influence of estrogen on hepatic cholesterol metabolism and biliary lipid secretion in rats fed fish oil

Both estrogen and dietary n-3 polyunsaturated fatty acids are known to be hypocholesterolemic, but appear to exert their effects by different mechanisms. In this study, the interaction between dietary fish oil (rich in n-3 polyunsaturated fatty acids) and estrogen in the regulation of hepatic cholesterol metabolism and biliary lipid secretion in rats was studied. Rats fed a low fat or a fish oil-supplemented diet for 21 days were injected with 17alpha-ethinyl estradiol (5 mg/kg body weight) or the vehicle only (control rats) once per day for 3 consecutive days. Estrogen-treatment led to a marked reduction in plasma cholesterol levels in fish oil-fed rats, which was greater than that observed with either estrogen or dietary fish oil alone. The expression of mRNA for cholesterol 7alpha-hydroxylase was decreased by estrogen in rats fed a low fat or a fish oil-supplemented diet, while the output of cholesterol (micromol/h/kg b.wt.) in the bile was unchanged in both groups. Cholesterol levels in the liver were increased by estrogen in rats given either diet, but there was a significant shift from cholesterol esterification to cholesteryl ester hydrolysis only in the fish oil-fed animals. Estrogen increased the concentration of cholesterol (micromol/ml) in the bile in rats fed the fish oil, but not the low fat diet. However, the cholesterol saturation index was unaffected. The output and concentration of total bile acid was also unaffected, but changes in the distribution of the individual bile acids were observed with estrogen treatment in both low fat and fish oil-fed groups. These results show that interaction between estrogen-treatment and dietary n-3 polyunsaturated fatty acids causes changes in hepatic cholesterol metabolism and biliary lipid secretion in rats, but does not increase the excretion of cholesterol from the body.

Iron deficiency enhances cholesterol gallstone formation

BACKGROUND

Cholesterol gallstones occur most commonly in multiparous women, but the causes for this phenomenon remain unclear. This same patient population is prone to chronic iron deficiency anemia. In addition, iron is known to play an important role in hepatic enzyme metabolism. Therefore, we tested the hypotheses that iron deficiency would alter hepatic cholesterol metabolism and enhance gallstone formation.

METHODS

Forty adult prairie dogs were fed either a control iron-supplemented (200 ppm), an iron-deficient (8 ppm), a 0.4% cholesterol iron-supplemented (200 ppm), or a 0.4% cholesterol iron-deficient (8 ppm) diet. After 8 weeks gallbladder bile, serum, and liver were harvested. Gallbladder bile was examined for cholesterol crystals and gallstones. Bile lipids and hepatic enzymes were measured, and a cholesterol saturation index (CSI) was calculated.

RESULTS

Animals receiving the iron-deficient diet were more likely to have cholesterol crystals in their bile than were animals on the control diet (80% vs. 20%; p < 0.05). Animals on the 0.4% cholesterol iron-deficient diet had more cholesterol crystals per high-powered field (79 +/- 10 vs. 49 +/- 9; p = 0.07), a higher molar % cholesterol (6.0 +/- 0.3 vs 4.4 +/- 0.5; p < 0.05), and a higher CSI (1.27 +/- 0.10 vs. 0.91 +/- 0.07; p < 0.05) compared to animals receiving the 0.4% cholesterol iron supplemented diet. The 7 alpha-hydroxylase levels were lower in the animals on the iron-deficient diet compared to those receiving the control diet (0.42 +/- 0.08 vs 1.17 +/- 0.40 pmol/mg per minute; p = 0.07).

CONCLUSIONS

These data suggest that an iron-deficient diet (1) alters hepatic enzyme metabolism, which, in turn, (2) increases gallbladder bile cholesterol and promotes cholesterol crystal formation. We conclude that iron deficiency plays a previously unrecognized role in the pathogenesis of cholesterol gallstone formation in women.

Age, sex and source of hamster affect experimental cholesterol cholelithiasis

In the present study, we examined the effect of the following factors on a hamster model of cholesterol cholelithiasis: (i) the source of the golden Syrian hamsters (Sasco, Omaha, NE or Charles River, Wilmington, MA), (ii) the sex of the experimental animals and (iii) their age (4 wk vs. 8 wk of age). All hamsters were fed a semipurified diet which contained cholesterol (0.3%) and palmitic acid (1.2%). No cholesterol gallstones formed in any of the female hamsters regardless of age or source. The 4-week-old male hamsters from Sasco had the greatest incidence of gallstones (93%). The 8-week-old male hamsters tended to have a lower incidence of cholesterol gallstones than the younger ones, regardless of the commercial supplier (67 vs. 93% for Sasco and 27 vs. 40% for Charles River). Female hamsters had higher liver and serum cholesterol levels than the male hamsters; Charles River hamsters had lower serum cholesterol concentrations than the Sasco animals. Total biliary lipid concentrations were highest in Sasco male hamsters, but biliary cholesterol (mol%) was lower in the males than in the females (4.2-4.5% vs. 6.1-7.1%) regardless of age. The cholesterol saturation indices were higher in the Sasco females than the corresponding males; these values were lower in the Sasco hamsters than the Charles River animals, regardless of age or sex. The male Sasco hamsters had a higher total biliary bile acid concentration (98.9 mg/mL) than the Sasco females (58.9 mg/mL) and the Charles River animals (24.6 mg/mL for males and 38.2 mg/mL for females). The percentage of chenodeoxycholic acid in bile was significantly lower, and the percentage of cholic acid was higher in all females as compared to males.(ABSTRACT TRUNCATED AT 250 WORDS)

Sex differences in colonic function: a randomised trial

There are sex differences in large bowel cancer rates and a variety of other gastrointestinal disorders possibly because of differences in gut biology. To determine whether men and women have different gastrointestinal responses when consuming identical intakes of dietary fibre, 16 women and 18 men consumed liquid formula diets and 'quick breads' with 0 g, and 10 g, and 30 g of fibre as wheat bran and vegetable fibre. The five test diets were consumed in random order, each treatment lasting 23 days. Mean transit time was faster (p = 0.02), and stool weights (g/day) were greater (p = 0.0005) for men than women. Neutral detergent fibre (NDF) excretion was greater in men (p = 0.01), and women tended to digest more NDF (p = 0.06). Men and women seemed to respond differently to wheat bran and vegetable fibre with regard to NDF excretion and digestibility. There were no gender differences in the faecal pH or moisture content. Concentrations and daily excretion of the secondary bile acids, lithocholic and deoxycholic acid, were greater for men than women (p < 0.05). Gender differences in bowel function and bile acid excretion, observed when men and women consumed the same amounts of dietary fibre, may be relevant for understanding colonic disease aetiology and for undertaking future dietary intervention trials.

Hepatobiliary complications of oral contraceptives

Complications secondary to the use of oral contraceptive agents are rare. Hepatobiliary complications, while often dramatic in presentation, occur infrequently. In a patient without predisposing conditions to complications, the benefits achieved with estrogen/progesterone products outweigh the risks. Those conditions that would absolutely and relatively contraindicate the use of oral contraceptives are listed in Table 4. Patients with a past history of liver disease in whom liver function tests have returned to normal may tolerate the introduction of oral contraceptives. They need to be monitored closely for adverse reactions. Patients who have experienced cholestatic jaundice of pregnancy should avoid all contraceptives because of a high risk of disease recurrence. Women whose first-degree relatives have experienced cholestasis of pregnancy or oral contraceptive-induced cholestasis may be at increased risk and should be closely monitored while taking birth-control pills. Women with current or previous benign or malignant hepatic tumors should not take oral contraceptives. Active hepatitis is an absolute contraindication to using birth control pills, although patients with a past history of hepatitis and no evidence of active disease can have a trial of these drugs with close follow-up. A final group of women who should avoid oral contraceptives is those with familial defects of biliary excretion, including the Dubin-Johnson syndrome, Rotor's syndrome, and benign intrahepatic recurrent cholestasis. Dubin-Johnson syndrome is often asymptomatic and may manifest only during pregnancy or during the use of oral contraceptives. The reduction in hepatic excretory function induced by the sex steroids can transform the mild hyperbilirubinemia into frank jaundice. Oral contraceptive agents are the most widely used reversible means of birth control currently available. Fortunately, the complications associated with these drugs are infrequent and may be decreasing due to lower-dose products. Complications still occur, however, and need to be recognized by the general internist as medication-induced problems so the offending drugs can be discontinued and appropriate treatment and follow-up initiated. In addition, patients at risk for the development of complications need to be recognized and advised prior to the introduction of oral contraceptives.

Cholelithiasis and teenage mothers

Between 1980 and 1988, 23 female adolescents were hospitalized at the Bronx-Lebanon Hospital Center for symptomatic cholelithiasis. The known risk factors for gallstone formation in adolescents were considered. In ten of the patients (43%), none of the risk factors was present. All ten patients, however, had in common a recent history of pregnancy. This finding is consistent with the current literature on the possible mechanism of gallstone formation during pregnancy.

A case-control study of gallstones: a major risk factor for biliary tract cancer

Because of the strong association between gallstones and biliary tract cancer, we conducted a case-control study of gallstones at Niigata Cancer Center Hospital. Eighty-six cases with gallstones (33 males and 53 females) and 116 hospital controls (56 males and 60 females) were surveyed by means of a self-administered questionnaire. Gallstones were categorized into cholesterol stones (25 cases) and pigment stones (30 cases) based on the appearance of the stones. In multivariate analyses based on an unconditional logistic regression model, the risk of total gallstones was positively associated with a taste for salty food (relative risk (RR) = 2.31, 95% confidence interval (CI): 1.10-4.84), an intake of lettuce and cabbage (RR = 2.98, 95% CI: 1.47-6.06) and a family history of biliary diseases (RR = 5.63, 95% CI: 1.76-17.95), and inversely associated with an intake of salted and dried fish (RR = 0.16, 95% CI: 0.04-0.64). When analyzed by type of stones, cholesterol stones were associated with a taste for oily food (RR = 3.87, 95% CI: 1.36-11.03) and pigment stones were positively associated with professional or administrative occupation (RR = 4.74, 95% CI: 1.35-16.68) and inversely associated with a taste for less greasy food (RR = 0.28, 95% CI: 0.10-0.83). Some of these results are consistent with the results of our previous study on biliary tract cancer.

A case-control study of biliary tract cancer in Niigata Prefecture, Japan

A case-control study of biliary tract cancer was conducted in Niigata prefecture where the mortality of the cancer is the highest in Japan. The cases were 109 patients with gallbladder cancer and 84 with bile duct cancer, and the controls were 386 sex- and age-matched neighborhood controls. For gallbladder cancer, a past history of biliary tract disease, a positive family history of cholelithiasis and a taste for oily foods were high risk factors. Intakes of animal proteins and fats such as fish, eggs, meat, etc., ingestion of vegetables and fruits, and taking snacks were low risk factors for gallbladder cancer. For bile duct cancer, a past history of biliary tract disease, a family history of cerebral vascular accident, a thin constitution and taking a small amount of foods were high risk factors, and a family history of heart disease, obesity, intakes of alcohol, animal proteins and fats, or frequent intakes of vegetables and fruits were low risk factors.

Sludge and stones in gallbladder after pregnancy. Prevalence and risk factors

The prevalence of sludge and stones in the gallbladder of 298 women in the immediate post-partum period was ultrasonographically assessed. We have investigated some risk factors for the development of sludge or stones in these patients and followed up most of these patients by ultrasonography to detect the presence of sludge and/or stones in the year following their discovery. We found sludge in 80 (26.2%) and gallstones in 16 (5.2%) of these patients. Age, obesity and months of oral contraceptive use were risk factors only for the presence of gallstones. After 1 year of follow-up only 2 out of 45 patients with sludge but 13 out of 15 patients with gallstones still had abnormal ultrasonographic findings.

Direct measurements of enterohepatic circulation of bile acids in the cat. Influence of contraceptive steroids and oophorectomy

Contraceptive steroids that increase the risk of gallstones reduce the bile acid pool size and increase the cholesterol saturation in bile. To analyze mechanisms behind these effects, bile acid enterohepatic circulation was studied with direct methods in cats treated with peroral contraceptive steroids for 3 months, cats oophorectomized 1-2 months before study, and female control animals. Both administration of contraceptive steroids and oophorectomy reduced the bile acid pool size and bile acid synthesis rate. Contraceptive steroids increased water secretion by the liver at low bile acid secretion rates, reduced bile acid accumulation in the gallbladder, and increased the recycling rate of the bile acid pool. Oophorectomy did not significantly change the relation between bile acid and water secretion by the liver. The reduced bile acid pool size in animals receiving contraceptive steroids can be explained by an increased recycling rate induced by an enhanced water secretion by the liver. The possibility of a direct effect on the hepatic synthesis of bile acids by both administration of contraceptive steroids and oophorectomy cannot be excluded.

Influence of pregnancy, oophorectomy and contraceptive steroids on gall bladder concentrating function and hepatic bile flow in the cat

Pregnancy and contraceptive steroids are associated with a raised incidence of cholesterol gall stone disease. In pregnancy there is an increase in the size of the gall bladder. Investigation of hepatobiliary function in man and mammals has not established if the enlarged gall bladder is simply dilated, or if the absorptive capacity of the mucosa has changed. In the present study the concentrating function of the gall bladder and bile secretion from the liver were studied in pregnant animals, oophorectomised animals and animals treated for three months with contraceptive steroids. The effects of intravenous administration of prolactin, progesterone and oestrogen were studied in oophorectomised animals. It was found that the net rate of water absorption in the gall bladder of pregnant animals was doubled, while oophorectomy and contraceptive steroids did not affect this variable. The volume outflow of bile was enhanced in pregnant animals and in animals treated with contraceptive steroids. Intravenous infusions of prolactin, oestrogen or progesterone were found not to influence gall bladder concentrating function, nor hepatic bile secretion in oophorectomised animals.

Oral contraceptives, pregnancy, and endogenous oestrogen in gall stone disease--a case-control study

A case-control study of gall stone disease in women in relation to use of contraceptives, reproductive history, and concentrations of endogenous hormones was undertaken. The study population comprised 200 hospital patients with newly diagnosed gall stone disease, 182 individually matched controls selected from the community, and 234 controls who were patients in hospital. Use of oral contraceptives was associated with an increased risk of developing gall stones among young subjects but a decreased risk among older subjects. The risk of developing gall stone disease increased in association with increasing parity, particularly among younger women. The risk fell with increasing age at first pregnancy, independent of parity. Mean urinary excretion over 24 hours of oestrone, but not of pregnanediol, was significantly (p less than 0.05) greater for postmenopausal patients than controls. The age dependence of the relative risk associated with exposure to oral contraceptives and pregnancy suggests that there are subpopulations of women susceptible to early formation of gall stones after exposure to either oral contraceptives or pregnancy.

Cholecystitis in teenage girls

Cholecystectomy was carried out in 17 teenage girls for cholecystitis at Virginia Mason Hospital, Seattle, between 1971 and 1980. The incidence increased with increasing age. Gallbladder disease was associated with recent pregnancy or birth control pill use (71%), obesity (65%) and family history of gallbladder disease (47%). All but one patient had at least one of these risk factors. No patient had congenital anomalies, blood dyscrasias or other underlying illness. Patients most commonly had recurrent attacks of abdominal pain; seven had symptoms for more than six months. Although the clinical presentations were often mild, six patients had jaundice, three had chemical pancreatitis, one had hemorrhagic pancreatitis, one had pancreatic pseudocyst and abscess and one had a common duct stone. One patient had cholesterosis and 16 had cholelithiasis. All patients were cured by operation. During the same time period, only two boys, both aged 14 years, nonobese and with no family history of gallbladder disease, underwent cholecystectomy, both for acaculous cholecystitis.

Effects of synthetic steroid contraceptives on biliary lipid composition of normal Mexican women

The effects of two hormonal contraceptives upon the biliary lipid composition of Mexican women were evaluated in a prospective study. Twenty-one healthy volunteers of reproductive age were allocated into three groups (7 subjects each). Group I served as the experimental control (all subjects were bearing a non-medicated IUD), group II received i.m. norethisterone enanthate (NET-e) 200 mg every two months, and group III received an oral combination of 1-norgestrel 150 micrograms and ethinyl estradiol 30 micrograms. The bile lithogenic index as assessed by the relative proportion of cholesterol to bile acids and lecithin was determined in duodenal bile samples obtained before (baseline), during (4 months), and after (12 months) contraceptive administration. The results indicated that NET-e administration resulted in a slight although significant increase of the lithogenic index while the oral formulation did not. The overall data were interpreted as demonstrating that administration of these steroid contraceptives does not constitute a risk factor in terms of gallstone formation in the population studied. The estrogen-like behavior exhibited by NET-e is discussed.

Effect of synthetic oestrogens and progestagens in oral contraceptives on bile lipid composition

The prevalence of cholesterol gall stones in young women has increased since the introduction of oral contraceptives. The synthetic female sex hormones used in these preparations, increase the degree of cholesterol saturation in bile. To determine whether oestrogens, progestagens, or both, are responsible for the change in biliary cholesterol saturation index, a prospective randomised, controlled study was performed. A significant increase in the cholesterol saturation index of bile was observed when either 30 micrograms ethinyloestradiol plus 150 micrograms norgestrel (p = 0.01) or 50 micrograms ethinyloestradiol plus 250 micrograms norgestrel (p less than 0.01) were ingested daily for two months. No change in the cholesterol saturation index was observed when 30 micrograms ethinyloestradiol alone, or 30 micrograms ethinyloestradiol plus 2.5 mg norethisterone were used. The mechanism for the increase in cholesterol saturation index did not appear to involve bile acid metabolism. These results indicate that the progestagen, norgestrel, and not as previously thought the oestrogen, ethinyloestradiol, is responsible for the increase in cholesterol saturation of bile which accompanies the use of oral contraceptives.

The influence of oral contraceptives on the composition of bile

The increased risk of cholelithiasis during intake of oral contraceptives may be due to estrogen-induced saturation of the bile with cholesterol. In a randomized, prospective, crossed-over double-blind study 20 healthy women after roentgenological exclusion of gall-stones received either 1.0 mg of norethindrone acetate and 50 microgram ethinyl estradiol daily - as usual in oral contraception - for 21 days with 7 days of placebo treatment in each cycle or one fifth of this hormone dose in form of a continuous daily medication. After a 4 month's treatment the medication form was crossed-over. At the beginning of the study, before the cross-over and after the study bile was collected by duodenal intubation after a 12-h fast and the lithogenic index as a measure for cholesterol saturation of the bile was determined. No correlation between the dose and the lithogenic index was demonstrated, neither in 15 women, who had used oral contraceptives before the study nor in five women without any previous hormonal contraceptives.

A human gallbladder adenocarcinoma cell line

A continuous cell line, COLO 346, was established from a liver metastasis in a patient with adenocarcinoma of the gallbladder. COLO 346 grew as an adherent monolayer of pleomorphic epithelioid cells. COLO 346 cells produced esterone, but no estradiol, progesterone, or cortisol. No adrenocorticotropic hormones, beta-subunit of human chorionic gonadotropin, carcinoembryonic antigen, or alpha-fetoprotein production by the cells was detected. Cell doubling time was 36 h. Seven allelic isozymes were assayed. COLO 346 had a chromosome mode of 74 at 21 months postestablishment with 6 marker chromosomes present in 100% of the cells analyzed. COLO 346 has been in continuous culture for over 2 yr and is available to other investigators for their studies.

Oral contraceptives raise the cholesterol saturation of bile by increasing biliary cholesterol secretion

To discover the mechanism by which oral contraceptives increase the level of cholesterol saturation of human bile, we measured biliary lipid secretion rates, gallbladder and hepatic bile lipid composition, bile acid pool size, bile acid composition, and plasma lipoprotein levels in five healthy women during routine oral contraceptive treatment and again during normal menstrual cycles on no medication. The molar percent cholesterol in both gallbladder and hepatic bile was higher in every subject while taking oral contraceptives (p less than .02). Oral contraceptive usage was accompanied by a significant enhancement of biliary cholesterol secretion (65 versus 46 mg/hr, p less than .01), but there was no significant change in bile acid or phospholipid secretion, total bile acid pool size, or bile acid composition. These findings indicate that oral contraceptive usage increases biliary cholesterol secretion, thereby raising the level of cholesterol saturation of bile and predisposing to cholesterol precipitation and gallstone formation.

Liver and gastrointestinal function in pregnancy

Difficulties arise in the interpretation of liver tests in the pregnant subject, since some values increase (alkaline phosphatase) whilst others remain unchanged (transaminases) or fall during pregnancy. The diagnosis and management of some causes of jaundice in pregnancy, such as viral hepatitis, gall stones, benign intrahepatic cholestasis and acute fatty liver of pregnancy are discussed. Little is known about the commonest symptoms of pregnancy (nausea, vomiting and constipation) other than that they might be due to hormonally induced alteration of sphincter tone. However, pre-existing bowel disease has a greater effect on pregnancy. Fertility is reduced in poor nutritional states (e.g. coeliac and Crohn's diseases) and an increased occurrence of spontaneous abortion has been noted. For inflammatory bowel diseases, the time of onset is important in determining the outcome of pregnancy. Relapse in the disease is commonest in the first trimester and in the puerperium. Treatment of these conditions is essentially as in the non-pregnant subject. The controversial subject of sulphasalazine and steroid usage in pregnancy is discussed.

Pancreatic enzyme levels in bile of patients with extrahepatic biliary tract disease

A total of ninety three patients with biliary tract disease were studied to determine the concentration of the pancreatic enzymes, amylase and lipase, in bile obtained from the gallbladder and/or common bile duct. Of seventy gallbladder bile samples, amylase levels were higher than actual or predicted serum levels in 87 per cent, while bile lipase were higher than serum lipase values in 66 per cent. Bile obtained from the common bile duct had enzyme concentrations which fluctuated from values similar to those in serum to remarkably high levels. This suggests that pancreatic enzymes enter the biliary system through a common terminal ampulla which is known to exist in 60 to 90 per cent of human subjects. The premise is advanced that pancreatic enzymes may initiate inflammatory changes in the gallbladder and could play a role in gallstone formation by altering the constituents which maintain cholesterol in a soluble state. Biliary reflux of pancreatic enzymes could play a role in the pathogenesis of some cases of cholecystitis can cholelithiasis.

Sex differences in the size of bile acid pools

In view of the excess prevalence of gallstones among women and the association of gallstones with diminished bile acid pool size, we measured bile acid pools in 27 male and 25 female healthy human volunteers. The average bile acid pool in the women was significantly smaller than in the men (2.25 +/- .12 g versus 2.88 +/- .16 g; p = 0.003). Chenodeoxycholic acid pool size, computed from bile acid composition data available in 43 of these subjects, was also smaller in women than men (0.94 +/- 0.06 versus 1.22 +/- 0.07 g; p = 0.004). Age, race, and body size bore no statistically significant relationship to bile acid pool size. Biliary cholesterol saturation was positively correlated with weight and obesity and showed a significant inverse correlation with chenodeoxycholic acid pool size, but not with total bile acid pool size. These findings suggest a possible mechanism for the higher prevalence of gallstones among women.

Fluctuations of serum and bile lipid concentrations during the menstrual cycle

We measured fasting serum and bile lipid concentrations at three intervals during the normal menstrual cycles of 11 healthy women not taking oral contraceptives. In nine of them cholesterol saturation of bile, and therefore presumably the risk of developing gall stones, was higher nine days after midcycle than at the end of menstruation. This change in bile cholesterol saturation was preceded by a significant fall in serum lipid concentrations: during the nine days after mid-cycle serum triglyceride and cholesterol concentrations fell in nine and eight of the 11 women respectively. Changes in the composition of serum and biliary lipids during the menstrual cycle are presumably due to a direct effect of sex hormones on the liver.

Evaluation of a new monkey model for the repeated study of bile secretory physiology

An unchaired monkey model for the repeated long-term study of biliary secretory physiology is reported. Postoperative management with cholre recorded. Evaluation was performed by repeated measurement, over a period of months, of bile flow and 14C erythritol clearance at three rates of taurocholate infusion given intravenously in a random order. Response to secretin was tested at the final infusion rate of taurocholate for each experiment. The outcomes of 9 monkeys were described of which 5 were repeatedly studied. They demonstrated an increase in bile flow and 14C erythritol clearance with increasing bile salt output. A dramatic choleresis over a wide range of bile salt excretion was noted with secretin and a linear relationship between bile bicarbonate output and bile salt secretion rate was observed. The new model has several major advantages and gives higher bile flows than previously recorded in the chaired model.

Comparison between the use of oral contraceptives and the incidence of surgically confirmed gallstone disease

A causal relationship between the use of oral contraceptives and gallstone disease has been proposed. If this is true, it is reasonable that the incidence of cholecystectomy in women of exposed ages should increase. In the present study a statistical analysis of the change in the incidence of cholecystectomy in women between 1961, i.e. 4 years before, and 1971, i.e. 6 years after, the introduction of oral contraceptives in Sweden was performed. To delimit uncontrolled factors, such as diet and attitude towards surgery, the change in incidence of cholecystectomy in women was compared with the corresponding change in men during these years. The results indicate an increased incidence of cholecystectomy in women in age groups exposed to oral contraceptives. These findings support a causal relationship between the use of oral contraceptives and the incidence of gallstones in the population.

Gallbladder disease in children and adolescents

Seventy-nine patients, twenty years old or younger, with cholecystitis underwent cholecystectomy during a five year period at Santa Rosa Medical Center. There was a considerable delay in diagnosis in many cases. Etiologic factors differed with race and age; however, the disease appears to be quite similar in adolescents and adults. Hemolytic disease was present in all five blacks but in none of the remaining seventy-four patients. Patients younger than ten years of age are more likely to have congenital anomalies or infectious etiologies for the gallbladder disease. Cholecystectomy was associated with minimal morbidity and no mortality in this series. Cholecystitis should be considered early in the child or adolescent with unexplained abdominal pain, and oral cholecystograms proved to be a safe and reliable method of diagnosis.

Kinetic analysis of biliary lipid excretion in man and dog

To understand better the mechanisms involved in biliary lipid excretion and to evaluate their role in cholesterol gallstone formation, the rates of biliary excretion of bile salts, cholesterol, and phospholipids were measured in two species, man and dog. Seven cholecystectomized patients with balloon-occludable reinfusion T-tubes were studied during intact and interrupted enterohepatic circulation and four cholecystectomized dogs were studied during interrupted enterohepatic circulation. In man and dog both cholesterol and phospholipid outputs were hyperbolically related to bile salt output by the equation y = x/(a + bx). The output curves intersected the origin and showed an initial rapid rise, followed by a slower increase to a maximum, suggesting a rate-limited mechanism. The shape of the curves permitted calculation of the theoretical maximal outputs and the rates of rise to those outputs. Comparison of these values showed that in both man and dog phospholipid output was greater than cholesterol output and that cholesterol and phospholipid were excreted at different rates. These studies (a) indicate that cholesterol, phospholipids, and bile salts are not excreted in a fixed relationship and (b) demonstrate the usefulness of the derived theoretical maximal lipid output, and the rate of rise of lipid excretion to a maximum, in evaluating the kinetics of biliary lipid excretion.

Effects of oral contraceptives on the gallbladder bile of normal women

In view of the reported association between use of oral contraceptives and gallbladder disease, the effects of contraceptive steroids on the lipid composition of gallbladder bile were studied in 22 healthy women. Each subject was studied during routine use of oral contraceptives and also during normal menstrual cycles on no medication. Gallbladder bile was significantly more saturated with cholesterol during contraceptive therapy than during normal menstrual cycling (125 versus 92 per cent, P less than 0.001). Chenodeoxycholic acid accounted for a significantly smaller proportion (35 versus 42 per cent P less than 0.001) and cholic acid a significantly greater proportion (50 versus 41 per cent (P less than 0.001) of total bile acids during contraceptive steroid therapy. These findings show that exogenous sex steroids in doses and formulations routinely prescribed induce important alterations in the composition of human gallbladder bile, and suggest a biochemical basis for the increase in gallbladder disease observed among women using oral contraceptives.