Viscosity and osmolality of abnormal biles.

The mean osmolality of bile from the common bile duct is similar to that of bile obtained from the gallbladder of patients with non-functioning gallbladders, and both means are significantly lower than the mean of bile in functioning gallbladders. The mean viscosity of bile from both functioning and non-functioning gallbladders is on average considerably greater than that from the common bile duct, and the mean viscosity of bile from non-functioning gallbladders is greater than that from functioning ones. The presence of much mucus in gallbladders containing stones is likely to account for these differences in viscosity. The composition of the gallstones does not appear to have any influence on these observations, but the number of patients in each group is too small for the differences to be significant.     

Occurrence of cholesterol crystals in human bile

The occurrence of cholesterol crystals was studied in 20 consecutive gallstone patients with functioning gallbladders. The frequency with which crystals were found rose sharply with the number of stones. Gallbladder bile was found more often to contain cholesterol crystals than hepatic bile of the same individual. Such crystals were absent in T tube drain bile from 10 consecutive choledochostomy patients, studied after the reestablishment of the enterohepatic circulation for at least five days. In gallstone patients in whom the gallbladder was visualized at cholecystography the hepatic bile contained cholesterol crystals more often than in patients with gallbladders not so visualized. In the latter patients the crystals tended to disappear after prolonged fasting. Bile analysis showed hepatic bile of patients with non-functioning gallbladders to be less lithogenic than bile in cases with functioning gallbladders. In the former group bile contained relatively more chenodeoxycholic acid than in the latter. The composition of bile with cholesterol crystals did not differ significantly from that of bile without crystals. In the final analysis it is important to identify possible factors responsible for the precipitation of cholesterol from supersaturated bile.     

GALLSTONE DISSOLUTION IN MAN USING CHENODEOXYCHOLIC ACID

The bile acid, chenodeoxycholic acid, Summary has been used in the " medical " treatment of patients with presumed cholesterol gallstones. In fifteen patients with normally functioning gallbladders, bile lipid composition was measured before and after 3 months of bile-acid therapy. Chenodeoxycholic acid treatment significantly improved cholesterol solubility in bile as shown by an increase in the cholesterol solubilising capacity of bile (the bile-salt + phospholipid/cholesterol ratio) and by a reduction in the molar ratio of cholesterol in bile. Twelve gallstone patients with " functioning " gallbladders have had repeat X-rays after 6 months of medical therapy. In three patients the gallstones have disappeared, in three the stones are appreciably smaller, while in six there has, as yet, been no change in gallstone size. Three patients with " non-functioning " gallbladders have shown no return of function after treatment. Fasting serum-lipids and circulating liver enzymes were measured at monthly intervals. Serum-triglyceride levels fell during treatment. The only abnormality in hepatic function was a slight rise in isocitric dehydrogenase levels.     

Increased biliary group II phospholipase A2 and altered gallbladder bile in patients with multiple cholesterol stones

BACKGROUND & AIMS: Multiple cholesterol stones are associated with more biliary complications and show more rapid cholesterol nucleation than solitary stones. Group II phospholipase A2 (PLA2-II) may play a critical role in the process of mucosal inflammation, which in turn may produce pronucleating agents. PLA2-II concentrations in gallbladders and gallbladder bile from patients with different types of gallstone disease were assayed to correlate PLA2-II with alterations in biliary composition. METHODS: PLA2-II protein concentrations were assayed immunoradiometrically using monoclonal antibodies against human splenic PLA2-II. RESULTS: Immunoreactive PLA2-II levels in gallbladder bile were significantly higher in patients with multiple cholesterol stones (68.2 +/- 6.3 ng/dL, mean +/- SEM; n = 24) than in those with solitary stones (24.9 +/- 2.8; n = 20; P < 0.01), those with multiple pigment stones (24.2 +/- 3.7; n = 18; P < 0.01), or control subjects (13.4 +/- 1.7; n = 19; P < 0.01). Increased biliary immunoreactive PLA2-II levels in multiple cholesterol stones were associated with a concomitant increase in the lysophosphatidylcholine to phosphatidylcholine ratio; free arachidonate, protein, and hexosamine concentrations; and gallbladder bile viscosity. The gallbladders showed an increased PLA2- II protein mass and steady-state messenger RNA levels, which was associated with increased prostaglandin E2 levels. CONCLUSIONS: Increased biliary PLA2-II may be of pathogenetic importance in multiple cholesterol stones, probably through potentiating gallbladder mucosal inflammation with associated biliary alterations favoring cholesterol crystal formation. (Gastroenterology 1997 Jun;112(6):2036-47)     

Composition of Basal and Stimulated Hepatic Bile in Baboons, and the Formation of Cholesterol Gallstones

The baboon, Papio, has been found to be a model for the study of the pathogenesis of cholesterol cholelithiasis in man. Studies of the physiologic variations in hepatic bile composition indicate a cyclic pattern to the proportions of cholesterol, lecithin, and bile salt in hepatic bile. During reabsorption of the bile salt pool from the intestines (stimulated flow), hepatic bile is characteristically undersaturated with cholesterol. After reabsorption of the bile salt pool (basal flow), hepatic bile is characteristically supersaturated with cholesterol. This typical pattern of basal and stimulated hepatic bile occurs irrespective of the presence of cholesterol stones in the baboon. Recognition of these two types of hepatic bile and their interrelationship during admixture in the gallbladder provides new insight into the pathogenesis of gallstone formation.     

Excretion of metroindazole in human bile. Investigations of hepatic bile, common duct bile, and gallbladder bile

Excretion of metronidazole (MNZ) in the normal and in the diseased biliary tract was investigated in 58 patients after oral or intravenous administration of MNZ. After oral administration MNZ appeared rapidly in hepatic bile, and throughout the period of absorption and elimination almost identical concentrations of MNZ were found in serum and hepatic bile. After intravenous administration no significant differences were found between concentrations of MNZ in common duct bile and serum in the non-obstructed common duct; in common duct obstruction, concentrations of MNZ in common duct bile were 56--99 per cent of corresponding concentrations in serum. MNZ was concentrated in normal gallbladders. In patients with gallbladder stones and preserved function of the gallbladder and in patients with no function of the gallbladder but a patent cystic duct, no significant differences were found between concentrations of MNZ in gallbladder bile, common duct bile, and serum. In most gallbladders with the cystic duct blocked by a stone, no MNZ was found in gallbladder bile.     

Detection of Helicobacter pylori by polymerase reaction in bile samples from gallbladder and bile stones

Some papers report helicobacter pylori existence in bile from surgical specimens obtained during gallbladder or bile ducts surgery. The aim of this work was search by PCR, H. Pylori presence in bile specimens from patients suffering of gallbladder stones or by bile ducts stones. Bile samples were obtained by gallbladder punction during cholecystectomy in 26 patients, 19 of them with gallbladder stones and 7 also with gallbladder stones and bile duct stones. Age ranged from 22-69 years old, median 49.6 years old. Samples were sent to specialized biomolecular laboratory to perform PCR techniques. Two of 26 patients (7.6%) had positive reaction for the presence of DNA of H. Pylori in bile samples. Our research suggest that DNA of H. Pylori can be founded in bile samples patients with gallbladders and duct stones in Argentina.     

Impaired human gallbladder lipid absorption in cholesterol gallstone disease and its effect on cholesterol solubility in bile

BACKGROUND & AIMS: The role of the gallbladder in gallstone pathogenesis is still unclear. We examined the effects of gallbladder mucosal lipid absorption on lipid composition and cholesterol crystallization in bile. METHODS: The in vitro-isolated, intra-arterially perfused gallbladder model was used (1) to compare the absorption rates of lipids from standard bile by gallbladders obtained from 7 patients with cholesterol gallstones and 6 controls; and (2) to measure the microscopic cholesterol crystal detection time in cholesterol-enriched pig bile before and after lipid absorption by the pig gallbladder. RESULTS: Control gallbladders, but not cholesterol gallstone gallbladders, significantly reduced cholesterol (P < 0.02) and phospholipid (P < 0.01) and increased bile salt (P < 0.01) molar percentages in bile over a 5-hour period by efficient and selective cholesterol and phospholipid absorption. A histomorphometric study of the epithelial cells showed significantly higher values for nuclear density (P < 0.01) and nuclear (P < 0.05) and cytoplasmic (P < 0.05) areas in the cholesterol gallstone than the control group. Sequential microscopy of cholesterol-enriched pig bile showed significantly shorter cholesterol filament (P < 0.01) and typical cholesterol plate (P < 0. 02) detection times before than after exposure of bile to the gallbladder lipid absorption. CONCLUSIONS: In cholesterol gallstone disease, the human gallbladder epithelium loses its capacity to selectively and efficiently absorb cholesterol and phospholipids from bile, even if it is hyperplastic and hypertrophic. This epithelial dysfunction eliminates the positive effect that the normal gallbladder exerts on cholesterol solubility in bile and might be a pathogenetic cofactor for cholesterol gallstone formation.     

Cholesterol crystals, cholesterol saturation of bile and biliary lithiasis

It has been repeatedly shown that normal human gallbladder bile is commonly supersaturated wih cholesterol. It has been therefore suggested that the crucial step of the formation of cholesterol gallstones might be the nucleation and growth of cholesterol monohydrate crystals. Consequently this work was aimed at determining: 1) if cholesterol crystal formation is really a typical feature of gallbladder bile with cholesterol gallstones; 2) the influence of the degree of cholesterol saturation of bile on the formation of cholesterol crystals. Gallbladder bile from 89 patients (23 from patients with cholesterol gallstones, 7 from patients with non-cholesterol gallstones and 59 from patients free of gallstones) and hepatic bile from 17 previously cholecystectomized patients were studied. Four of these patients had cholesterol stones of the common bile duct. Results: (a) gallbladder bile: cholesterol crystals were present on immediate examination in 19 of the 23 bile samples with cholesterol stones, in 2 of the 7 bile samples with non-cholesterol stones and in 1 of the 59 bile samples without stones. Only 1 bile sample with cholesterol stone developed crystals. Cholesterol saturation of bile with or without crystals did not differ significantly; (b) hepatic bile: cholesterol crystals were detected on immediate examination in one of the 17 bile samples and subsequently appeared in one of the remaining samples. Cholesterol saturation of hepatic bile (2.10 +/- 0.43) was significantly higher (p less than 0.01) than that of gallbladder bile containing cholesterol stones (1.32 +/- 0.43).(ABSTRACT TRUNCATED AT 250 WORDS)     

Calcium carbonate in human gallstones and total CO2 in bile

Measurement of total CO2 concentrations in bile from patients undergoing cholecystectomy because of gallstones has shown that the presence of calcium carbonate in the stones can be associated with a raised total CO2 concentration in the common duct bile. In bile from functioning and poorly-functioning gallbladders, total CO2 was nearly always related to pH irrespective of stone composition.     

Diurnal variations in the pH of pathological gallbladder bile.

The pH of gallbladder and common duct bile from patients undergoing surgery for cholecystectomy has been measured. The bile was collected and kept anaerobically at 37 degrees C, and the pH measured at 37 degrees C, generally within 30-60 minutes of the bile being taken from the patient. Only data from patients having functioning or poorly-functioning gallbladders were included in the calculations. The pH of common duct bile was always greater than that of the corresponding gallbladder bile, and the data available suggest that it does not vary diurnally. The mean pH of gallbladder bile from patients undergoing their operation at different times during the day shows a diurnal variation, the bile becoming more acidic with time. Furthermore, there is also a diurnal variation in the activity of the acidifying process. Data for the patients suggest this is retarded by sleep, inactivity, or lying down.     

The composition of hepatic and gallbladder bile in patients with gallstones

Bile specimens were obtained from 17 patients with gallstones and 21 patients with duodenal ulcer. The specimens were obtained from the former by needle aspiration of the gallbladder and common bile duct at operation and from the latter by duodenal intubation. The concentrations of bile salt, phospholipid, and cholesterol were measured. Gallbladder bile from gallstone patients contained significantly more cholesterol than did ;duodenal' bile from duodenal ulcer patients. Hepatic bile from gallstone patients contained significantly more cholesterol than did gallbladder bile from the same patients. When the data were plotted on triangular coordinates the relative composition lay within the zone of cholesterol solubility in all 21 ulcer patients. The relative composition of hepatic bile lay outside the zone of cholesterol solubility in five gallstone patients, at the limits of cholesterol solubility in a further three, and within the micellar zone in the remaining nine patients. This suggests that supersaturation of hepatic bile with cholesterol is not the sine qua non for the production of cholesterol gallstones.     

Outcome of gallbladder preservation in surgical management of primary bile duct stones

AIM: To evaluate the methods and outcome of gallbladder preservation in surgical treatment of primary bile duct stones. METHODS: Thirty-five patients with primary bile duct stones and intact gallbladders received stone extraction by two operative approaches, 23 done through the intrahepatic duct stump (RBD-IDS, the RBD-IDS group) after partial hepatectomy and 12 through the hepatic parenchyma by retrograde puncture (RBD-RP, the RBD-RP group). The gallbladders were preserved and the common bile duct (CBD) incisions were primarily closed. The patients were examined postoperatively by direct cholangiography and followed up by ultrasonography once every six months. RESULTS: In the RBD-IDS group, residual bile duct stones were found in three patients, which were cleared by a combination of fibrocholedochoscopic extraction and lithotripsy through the drainage tracts. The tubes were removed on postoperative day 22 (range: 16-42 days). In the RBD-RP group, one patient developed hemobilia and was cured by conservative therapy. The tubes were removed on postoperative day 8 (range: 7-11 days). Postoperative cholangiography showed that all the gallbladders were well opacified, contractile and smooth. During 54 (range: 6-120 months) months of follow-up, six patients had mildly thickened cholecystic walls without related symptoms and further changes, two underwent laparotomies because of adhesive intestinal obstruction and gastric cancer respectively, three died of cardiopulmonary diseases. No stones were found in all the preserved gallbladders. CONCLUSION: The intact gallbladders preserved after surgical extraction of primary bile duct stones will not develop gallstones. Retrograde biliary drainage is an optimal approach for gallbladder preservation.     

Biliary lipid output during three meals and an overnight fast. II. Effect of chenodeoxycholic acid treatment in gallstone subjects.

Oral treatment with chenodeoxycholic acid causes dissolution of cholesterol gallstones in man. In order to determine the mechanism of this effect, we have measured 24-hour biliary lipid output, lipid composition of fasting gallbladder bile, and bile acid pool sizes before and during such treatment in six patients with radiolucent gallstones in functioning gallbladders. In all six patients, the degree of cholesterol saturation of fasting-state gallbladder bile was decreased during treatment to a level below the thermodynamic solubility line. This effect was due to a decrease in biliary cholesterol output, associated with conversion of more than 90% of the total bile acid pool to chenodeoxycholic acid. It could not be attributed to an increase in total bile acid pool size nor to an increase in biliary bile acid or phospholipid output.     

Excess membrane cholesterol alters human gallbladder muscle contractility and membrane fluidity

BACKGROUND & AIMS: The relationship between muscle contractility, plasma membrane cholesterol, and fluidity was investigated in human gallbladders with gallstones. METHODS: Isolated gallbladder muscle cells were used to measure contraction. Plasma membranes of gallbladder muscle were purified in a sucrose gradient and measured for cholesterol content and cholesterol/phospholipid mole ratio. Membrane fluidity was determined by using fluorescence polarization and was expressed as the reciprocal of anisotropy. RESULTS: The maximal contraction induced by cholecystokinin octapeptide was significantly less in gallbladders with cholesterol stones than in those with pigment stones. The membrane cholesterol content and cholesterol/phospholipid mole ratio were significantly higher in gallbladders with cholesterol stones than in those with pigment stones. Membrane anisotropy was also higher than in gallbladders with pigment stones, reflecting lower membrane fluidity in gallbladders with cholesterol stones. After muscle cells from cholesterol stone gallbladders were incubated with cholesterol-free liposomes for 4 hours, cholecystokinin octapeptide-induced contraction, membrane cholesterol content and cholesterol/phospholipid ratio, and membrane fluidity returned to normal levels. CONCLUSIONS: Gallbladder muscle from patients with cholesterol stones has increased membrane cholesterol/phospholipid mole ratio and decreased membrane fluidity resulting in impaired muscle contractility. These abnormalities are corrected by removing the excess cholesterol from the plasma membranes.     

Biliary proteins and the nucleation defect in cholesterol cholelithiasis

A study was performed to determine whether differences in gallbladder proteins might be present in patients with rapidly nucleating bile. Gallbladder and hepatic bile protein concentrations were measured using a fluorometric assay. The method was validated by an independent technique, i.e., hydrolysis and amino acid analysis. Persons with cholesterol gallstones had significantly higher gallbladder bile protein concentrations than patients without gallbladder disease or patients with pigment stones. The protein concentration correlated with the in vitro nucleation time in the cholesterol stone group. Gallbladder bile proteins were also purified by chromatography and gradient ultracentrifugation. Proteins from patients with cholesterol gallstones accelerated the nucleation time of control bile, whereas protein from controls had little effect. Hepatic bile protein concentrations were similar in persons with and without cholesterol gallstones. The gallbladder-to-hepatic bile ratios of a variety of solutes were examined. The ratio for protein in the cholesterol gallstone group can be explained straightforwardly by water reabsorption in the gallbladder, whereas the very low ratio in patients without cholesterol gallstones suggests that their gallbladders reduce protein mass by a process such as protein absorption or degradation during water absorption in the gallbladder.     

Human gallbladder mucin accelerates nucleation of cholesterol in artificial bile

The gallbladder bile of patients with cholesterol gallstones is characterized by two abnormalities: (a) supersaturation with cholesterol and (b) accelerated nucleation of cholesterol monohydrate crystals. We studied the ability of purified human gallbladder mucin to nucleate artificial bile in vitro. Human gallbladder mucin at concentrations of 2 and 4 mg/ml accelerated the nucleation time of cholesterol crystals in model bile. The mean number of cholesterol crystals in artificial bile incubated for 10 days with 4 mg/ml of human gallbladder mucin was 2327/mm3 (p less than 0.01) vs. control of 51/mm3. The number of crystals found in model bile was dependent on the concentration of human gallbladder mucin (2-16 mg/ml) and the time of incubation (4-14 days). Human gallbladder mucin was associated with an increase in the number of liquid crystals after 4 days of incubation, which then decreased in number as solid cholesterol monohydrate crystals formed. Nucleation by human gallbladder mucin was significantly increased only with cholesterol saturation indices greater than 1.0, and in biles containing 10% but not 3% total lipid by weight. Pooled human gallbladder mucin from gallbladders with and without stones both increased nucleation significantly when compared with controls. Increased nucleation of saturated model bile was also observed with purified monkey cervical and bovine gallbladder mucin, but not with porcine gastric mucin. These observations provide further evidence that human gallbladder mucin may contribute to cholesterol gallstone formation in humans by accelerating nucleation of cholesterol monohydrate crystals from supersaturated gallbladder bile.     

Cholesterol nucleation time in gallbladder bile of patients with solitary or multiple cholesterol gallstones.

Patients with multiple cholesterol gallbladder stones have been found to be at a higher risk for the recurrence of gallstones after successful nonsurgical treatment than those with a solitary stone. Cholesterol gallstone recurrence, like primary gallstone formation, probably involves a triple defect with supersaturation, abnormally rapid nucleation of cholesterol in bile and altered gallbladder motor function. We investigated whether the increased recurrence rate of patients with multiple stones might be caused by more rapid nucleation. Therefore the time required for cholesterol monohydrate crystals to appear in ultracentrifuged bile of patients with solitary (n = 71) or multiple (n = 42) cholesterol gallstones was determined. The cholesterol nucleation time was significantly (p less than 0.01) longer in the bile from patients with solitary stones (less than 1 to 16 days, median = 2.0 days) than in the bile from patients with multiple stones (less than 1 to 8 days, median = 1.0 days). Moreover, 15 of 71 (21.1%) patients with solitary cholesterol stones but only 1 of 42 (2.4%) patients with multiple cholesterol stones showed a normal (greater than 4 days) nucleation time. However, no difference in the cholesterol saturation index was found between the bile samples from patients with solitary stones and the bile samples from patients with multiple stones (1.55 +/- 0.65 vs. 1.54 +/- 0.59, mean +/- S.D., respectively). The more rapid cholesterol nucleation in gallbladder bile may, therefore, be the major risk factor causing the higher percentage of stone recurrence in patients with multiple cholesterol stones as compared with patients with solitary cholesterol stones.     

Patients with uncomplicated cholelithiasis acidify bile normally

Reports have suggested that patients with gallstones have gallbladder bile that is less acidic and more saturated with calcium carbonate than patients without gallstones. This failure to acidify bile may play a role in the formation of gallstones. We, therefore, compared gallbladder bile pH, ionized calcium, and calcium carbonate saturation index from patients undergoing either incidental gallbladder removal (controls, n = 23) or elective cholecystectomy for gallstones (n = 55). Gallstones were classified as either cholesterol (n = 39) or black pigment (n = 16) stones. No difference in gallbladder bile pH was noted among the controls, cholesterol stone, and pigment stone patients. In addition, no difference in ionized calcium concentration or CCSI was noted among the three groups. The pH in additional patients (n = 49) with acute cholecystitis, common bile duct obstruction, biliary tract infection, and cystic duct obstruction was significantly more acidic. We conclude that neither a defect in bile acidification nor increased saturation of calcium carbonate explains why human cholesterol or pigment gallstones form.     

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).