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.     

Bile concentration is a key factor for nucleation of cholesterol crystals and cholesterol saturation index in gallbladder bile of gallstone patients

We investigated whether bile concentration influenced cholesterol saturation index or nucleation time of cholesterol monohydrate crystals in a large number of gallbladder bile samples. Pigment stone patients never had cholesterol crystals in their fresh biles, and nucleation time was always longer than 20 days. Of the cholesterol stone patients 79% had cholesterol crystals in their fresh biles. Long nucleation times were generally found in cholesterol stone patients with dilute biles despite a high cholesterol saturation index. Nucleation time was usually short if bile was well concentrated despite a relatively low saturation index. Serial in vitro dilution of concentrated biles from cholesterol gallstone patients resulted in progressively prolonged nucleation times. Patients with solitary cholesterol stones had longer nucleation times than patients with multiple cholesterol stones. This study indicates that bile concentration is an important factor for nucleation time and cholesterol saturation index. Moreover, solitary and multiple cholesterol stones may have a different pathogenesis.     

Nucleation time and lithogenic index in obese patients and in patients with cholecystolithiasis

The gallbladder bile of obese patients without gallstones is supersaturated with cholesterol. The cholesterol saturation index (CSI, LI) of 27 obese patients was 1.32 +/- 0.2. The CSI of 24 normal weight gallstone patients was determined with 1.16 +/- 0.37 and is therefore not significantly different from CSI of obese stone free individuals. The supersaturated bile from obese patients does not accelerated the nucleation of cholesterol crystals. The nucleation time of obese persons was statistically significant longer (16.0 +/- 3.0 days) than in gallstones patients (6.0 +/- 0.78 days) (p less than 0.001). In 50% of the patients with gallstones cholesterol monohydratcrystals were present in the native gallbladder bilde, whereas such crystals are found in only 3.7% of the obese group. Liquid crystals occurred more frequently and in larger number in the bile of the obese patients. The stone forming potency of gallbladder bile can be estimated better by the determination of nucleation time and cholesterol crystals occurrence than by the calculation of the saturation index (CSI).     

The Relation between Biliary Lipids,Nucleation Time,and Number of Gallbladder Stones after Percutaneous Gallbladder Puncture

Tudyka J, Kratzer W, Maier C, Mason R, Wechsler JG. The relation between biliary lipids, nucleation time, and number of gallbladder stones after percutaneous gallbladder puncture. Scand J Gastroenterol 1994;29:844-848.

Background: Biliary lipids and nucleation time are increasingly of importance in the understanding of the cholesterol nucleation process in gallstone patients. Methods: Biliary lipids, total lipid concentration (TLC), cholesterol saturation index (CSI) and nucleation time (NT) were studied in 221 bile samples from patients with solitary (n equals; 120) and multiple (n equals; 101) gallbladder stones. Results: Biliary cholesterol concentration and CSI did not differ between patients with solitary or multiple stones; however, it was positively correlated with the CSI (r equals; 0.93; p < 0.01). We found a negative correlation between CSI and TLC (r equals; ? 0.77 for solitary stones and r equals; ? 0.79 for multiple stones; p < 0.01). Furthermore, levels of total bile acids and phospholipids were similar in cases with solitary and multiple gallbladder stones. TLC did not correlate with single or multiple stones, whereas NT was determined to be negatively correlated with the number of gallstones (r= ?0.39; p<0.01). Patients with solitary stones had a significantly (p < 0.01) longer NT than those with multiple gallbladder stones (7.5 ± 4.2 days versus 2.3 ± 1.5 days). Conclusions: Our findings suggest that there exists a nucleation-promoting activity, which seems to be more pronounced in patients with multiple gallbladder stones than in those with solitary stones, indicating a major risk factor for the higher recurrence rate seen in these patients.     

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 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)     

Supersaturated bile from obese patients without gallstones supports cholesterol crystal growth but not nucleation

Cholesterol crystal formation was studied in gallbladder bile samples collected from 18 patients with cholesterol gallstones, 6 patients with black pigment stones, and 14 obese patients without gallstones. In the absence of seed crystals, bile from patients with cholesterol stones showed a much greater tendency to form cholesterol crystals in vitro than bile of similar cholesterol saturation from patients without cholesterol stones. The ability to form crystals was not related to the biliary hexosamine concentration, an indicator of mucin content. When small seed crystals of cholesterol monohydrate were added to each bile, the seed crystals dissolved in all biles (n = 8) with a cholesterol saturation index less than 0.76. In contrast, 29 of 30 biles with a cholesterol saturation index greater than 0.76 supported crystal growth, even when collected from patients without gallstones. These results indicate that the difference between supersaturated biles in the ability to form cholesterol crystals resides at the nucleation, rather than the growth, stage of crystal formation.     

Gallstone recurrence after successful dissolution therapy

After successful dissolution therapy of cholesterol gallbladder stones bile again becomes supersaturated and recurrent gallstones may develop. Three different postdissolution treatments [500 mg ursodeoxycholic acid (UDCA) per day (N=14, group I), 100 mg aspirin per day (N=14, group II) and diet (N=15, group III) versus a control group (no treatment,N=15, group IV) aimed at preventing recurrence of gallstones were investigated in a prospective, randomized study in 58 gallstone patients (33 female, 25 male) after complete stone clearance. Bile samples (prior to dissolution therapy and at stone recurrence) were investigated for biliary cholesterol (C), phospholipids (PL), total bile acid concentration (BA), cholesterol saturation index (CSI), total lipid concentration (TLC), total biliary protein concentration (TP), and nucleation time (NT). In group IV multiple gallstones tended to recur more often than solitary stones (66.7% vs 16.7%) whereas in groups I–III only solitary stones recurred. Recurrent gallbladder stones were detectable in 10 patients (eight patients in group IV and one each in groups I and II, respectively) within one year after dissolution and in two patients (one each in groups III and IV, respectively) after 15 months. Furthermore, the probability of stone recurrence was significantly higher in untreated patients as compared to treated patients. In nine (group IV) of 12 patients with recurrent stones NT, C, CSI, PL, BA, TLC, TP, and bile acid spectrum remained nearly unchanged as compared to their pretreatment values, whereas in three (groups I–III) of 12 cases a decrease in C, CSI, and TP was observed during therapy. However, in each of these three patients, initial and after-treatment TP was significantly higher and NT shorter as compared to groups I–IV. Furthermore, in these cases (N=3) NT was prolonged, whereas no significant changes were found in PL, BA, TLC, and bile acid spectrum. Recurrence of gallstones, which seems to occur more likely in patients with multiple stones as compared to solitary stones, will happen in the early stage after stone clearance, again causing biliary pain. UDCA, aspirin or diet will reduce the probability for recurrent stones after complete gallstone dissolution.     

Diagnostic value of fine-needle puncture of the gallbladder: Side effects,safety, and prognostic value

Bile sampling without the risk of contamination by pancreatic and duodenal secretions and avoiding unpredictable influences of general anesthesia during biliary surgery on biliary analytics are feasible with percutaneous puncture of the gallbladder. In 207 patients with gallstones, gallbladder puncture was performed under local anesthesia with a 22-gauge spinal needle under continuous real-time ultrasound guidance. Bile samples were investigated for biliary lipids and nucleation time. Complete aspiration of gallbladder bile could be achieved in all patients without complications such as bleeding, bile leak, or inflammation. Of these patients, 11.6% reported mild abdominal problems, 3.4% required analgetics, and in 1.0% biliary colics were observed. Elective cholecystectomy was performed in 1 patient. Of the bile samples, 10.1% were contaminated with bactobilia. Biliary lipids, cholesterol saturation index (CSI), total lipid concentration (TLC), and bacteriological contamination were independent of gallstone number, whereas patients with solitary gallbladder stones exhibited a significantly longer nucleation time (NT) in comparison with those with multiple stones. In patients with gallstones, fine-needle puncture of the gallbladder represents an important diagnostic procedure and can be performed within minutes without major side effects if performed by an experienced sonographer.     

Nucleation time and growth time in patients with cholesterol gallstone--factors affecting nucleation time and growth time and effect of UDCA and CDCA

Nucleation time (NT) and growth time (GT) were measured in gallbladder bile of patients with cholesterol gallstones. NT was significantly shortened (NT less than 10 days) in pure cholesterol stones but was moderately shortened (11 less than or equal to NT less than or equal to 21) in mixed and combination stones. GT also was accelerated (GT less than 7 days) in cholesterol stones. NT was shortened in increased biliary total protein, but on the contrary, was shortened in decreased apo A-I. NT of bile by UDCA therapy but not CDCA was extended. This suggests that increased apo A-I during UDCA therapy might imply extension of NT. The strong negative correlation between GT and CSI of bile suggests that CSI plays an important role in crystal growth.     

Cholesterol and pigment gallstone disease: comparison of the reliability of three bile tests for differentiation between the two stone types

Gallbladder biles and stones were obtained at 116 cholecystectomies for symptomatic gallstone disease. All 33 patients younger than 50 years had cholesterol stones, whereas 40% of the older patients had pigment stones. We compared the reliability of three different bile tests for the differentiation between cholesterol and pigment stone patients. Whereas both the presence of cholesterol monohydrate crystals in fresh gallbladder bile and a nucleation time less than or equal to 20 days in ultrafiltered gallbladder bile had a specificity of 100% for cholesterol gallstone disease, biliary supersaturation with cholesterol (cholesterol saturation index greater than 1.0) had a low specificity. The sensitivity of nucleation time less than or equal to 20 days for cholesterol gallstone disease was 78% in concentrated gallbladder biles (biliary total lipid concentration greater than or equal to 5 g/dl) but only 21% in dilute biles (biliary total lipid concentration less than 5 g/dl). In contrast, examination for the presence of cholesterol crystals in fresh bile was reasonably sensitive both in concentrated and dilute gallbladder biles (sensitivity, 84% and 72%, respectively). In addition, duodenal bile obtained from 16 patients (10 cholesterol, 6 pigment) before cholecystectomy showed cholesterol crystals in 7 of the cholesterol but in none of the pigment stone patients. We conclude that examination of fresh bile for cholesterol crystals is a specific and reasonably sensitive test for cholesterol gallstone disease.     

Alterations in Gallbladder Emptying and Bile Retention in the Absence of Changes in Bile Lithogenicity in Postmenopausal Women on Hormone Replacement Therapy

The role of female sex hormones in the pathogenesis of gallstones is well established. Pregnancy, contraceptive use, estrogen replacement therapy in postmenopausal women, and estrogen therapy in men for the treatment of prostatic carcinoma have been found to be associated with increased risk of cholesterol gallstones. Alterations in gallbladder emptying and in bile lithogenicity in postmenopausal women receiving hormone replacement therapy (HRT) have not been studied to date. The present study was undertaken to study the effect of HRT on gallbladder emptying and bile lithogenicity. Sixteen postmenopausal women were included in the study. None of the patients had gallstone disease and none had received prokinetic drugs, such as, erythromycin, metoclopramide, domperidone or cisapride, aspirin, and nonsteroidal antiinflammatory drugs. Gallbladder emptying (n = 16), bile microscopy (n = 7), cholesterol saturation index (CSI) (n = 7), and nucleation time (n = 7) were studied before and 3 months after HRT (conjugated estrogen, 0.625 mg, + medroxyprogesterone acetate, 2.5 mg, everyday). Fasting and residual volumes increased (fasting volume, 18.2 +/- 2.2 mL pre-HRT vs 27.6 +/- 3.2 mL post-HRT, P = 0.0003; residual volume, 3.9 +/- 0.6 mL pre-HRT vs 10.3 +/- 2.0 mL post-HRT, P = 0.00009) and ejection fraction decreased (78.2 +/- 2.5% pre-HRT vs 62.2 +/- 3.8% post-HRT; P = 0.0017) after 3 months of HRT. There was no change in CSI (2.32 +/- 0.36 pre-HRT vs 2.60 +/- 0.51 post-HRT; P = NS) or in nucleation time (19.0 +/- 1.2 days pre-HRT vs 17.6 +/- 1.3 days post-HRT; P = NS). None of the bile samples either pre-HRT or post-HRT showed cholesterol monohydrate crystals. Though impairment of gallbladder emptying occurs in the short term with HRT in postmenopausal women, there is no change in CSI and nucleation time.     

High vesicular cholesterol and protein in bile are associated with formation of cholesterol but not pigment gallstones

To examine the differentiating parameters between cholesterol and pigment gallstones, we compared the nucleation times, concentrations of biliary lipid and protein, and the distribution of vesicular cholesterol in gallbladder bile of 16 patients with cholesterol, eight patients with black pigment gallstones, and nine gallstone-free control patients. Cholesterol monohydrate crystals were present in the fresh bile of only the cholesterol gallstone group. The nucleation time was significantly faster in the cholesterol stone group (3.3±3.2 days) than in the other two groups (pigment stone: 15.8±6.6, control: 16.9±5.7). The cholesterol saturation indices and the distribution of vesicular cholesterol were significantly higher in the cholesterol gallstone group than those in the other two groups. The total biliary protein concentration was significantly (P<0.01) higher in the cholesterol gallstone group [2.57±1.91 (sd) mg/ml] than that in the black pigment stone group (1.09±0.59). All parameters in patients with black pigment gallstone were essentially similar to the controls. We conclude that the presence of cholesterol crystals, rapid nucleation time, high vesicular cholesterol distribution, elevated cholesterol saturation index, and high protein concentration are associated with cholesterol gallstones but not with black pigment gallstones.     

Pathogenesis of cholelithiasis in chronic pancreatitis]

The prevalence and the pathogenesis of gallstones in patients with chronic pancreatitis have never been studied prospectively. The aim of this study was to evaluate prospectively the prevalence of gallstones with ultrasonography and to look for markers of pigment or cholesterol stone formation in gallbladder bile. Ultrasonography was performed in 39 patients and detected gallstones in 7 patients and sludge in 3. Common bile duct and intrahepatic bile duct dilatation were observed in 16 and 13 patients, respectively. Liver biopsies were obtained in 31 patients and cirrhosis was found in 4. There were calcium bilirubinate granules in 7 of the 27 bile samples examined. Cholesterol crystals were not found in any case. The nucleation time (median: 21 days) was higher in patients with chronic pancreatitis than in patients with cholesterol stones (median: 2 days) (P < 0.001) but was not different from nucleation time in patients either free of stones (median: 21 days) or with pigment stones (median: 21 days). The cholesterol saturation index was similar in patients with chronic pancreatitis and in controls. The 2 patients with chronic pancreatitis who underwent cholecystectomy had pigment stones. Calcium bilirubinate granules were more frequent in patients with intrahepatic bile ducts dilatation (P < 0.02). In conclusion, this study demonstrates a high prevalence of cholelithiasis in chronic pancreatitis patients. Pigment stone formation could be favored by cholestasis.     

Nucleation time of gall bladder bile in gall stone patients: influence of bile acid treatment.

The time required for precipitation of cholesterol crystals (nucleation time, NT) was determined and related to the cholesterol saturation in gall bladder bile of gall stone free subjects (n = 11), patients with pigment stones (n = 3), and patients with cholesterol gall stones (n = 30) undergoing cholecystectomy. Seven of the gall stone patients had been treated with chenodeoxycholic acid (CDCA) and nine with ursodeoxycholic acid (UDCA), 15 mg/kg/day for three weeks before operation. NT was longer in gall stone free subjects (mean, 20 days), patients with pigment stones (14 days) and patients treated with CDCA (24 days) and UDCA (17 days) compared with untreated patients with cholesterol gall stones (1.5 days). In spite of low cholesterol saturation and prolonged NT, and in contrast to those treated with CDCA, four of the nine patients treated with UDCA had cholesterol crystals in their bile. These observations give further support to the concept that the mechanism for inducing gall stone dissolution may be different for CDCA and UDCA.     

Association between cholesterol-phospholipid vesicles and cholesterol crystals in human gallbladder bile

Rapid aggregation of cholesterol-phospholipid vesicles in gallbladder bile seems to be the first event in the production of cholesterol crystals, a prerequisite for cholesterol gallstone formation. We examined the amount of these vesicles in 33 human gallbladder biles in relation to biliary lipid composition and to the presence of cholesterol crystals. Biliary microscopy detected cholesterol crystals in all 19 biles from patients with cholesterol gallstones but in none of 14 biles from patients with pigment stones. Gel chromatography was used to separate vesicles and micelles in the native bile with an eluting buffer containing 10 mM sodium cholate to prevent disruption of micellar lipids. Cholesterol, phospholipid and bile salt concentrations were measured in every fraction collected. Bile acid, phospholipid, cholesterol and total lipid concentrations were not significantly different in samples with and without cholesterol crystals. The cholesterol saturation index (1.4 +/- 0.11 vs. 1.0 +/- 0.08) was significantly (p less than 0.01) higher in biles with crystals than without crystals. Gel filtration revealed a vesicular peak in addition to micellar fraction in 18 (23.1 +/- 3.2% of total cholesterol) of the 19 biles with crystals but only in three (15.7 +/- 2.4% of total cholesterol) of 14 biles without crystals. There was no relation between biliary lipid concentration or the cholesterol saturation index and the percentage of vesicular cholesterol in biles with or without crystals. The close association of vesicles and crystals in human gallbladder bile supports the contention that vesicles are important in the initial nucleation of cholesterol monohydrate crystals.     

Sensitivity and specificity of microscopic examination of gallbladder bile for gallstone recognition and identification

During cholecystectomy, gallbladder bile and gallstones were obtained from 77 patients and gallbladder bile was obtained from 39 patients free of stones (11 patients had biliary stenosis). According to their chemical composition, gallstones were classified as cholesterol (n = 46) or pigment (n = 31) stones. In patients with gallstones (a) cholesterol crystals better helped to identify cholesterol gallstones (sensitivity, 87%; specificity, 97%; positive predictive value, 97%) than did an abnormal cholesterol saturation index of bile (sensitivity, 93%; specificity, 48%; positive predictive value, 73%); (b) the presence of cholesterol crystals was significantly related to the cholesterol content of gallstones and the bile cholesterol saturation index; and (c) bilirubinate crystals, when present alone (without cholesterol crystals), were good predictors of pigment gallstones (sensitivity, 71%; specificity, 93%; positive predictive value, 88%). In the absence of stones, bilirubinate crystals were present in 9 of 28 patients without biliary stenosis (4 with alcoholic cirrhosis and 2 with alcoholic pancreatitis) and 8 of 11 patients with biliary stenosis. In the absence of stones, cholesterol crystals were present in 2 of 28 patients without biliary stenosis and in 4 of 11 patients with biliary stenosis, suggesting that bile stasis can induce cholesterol crystal formation.     

Decreased protein concentration and improved metastability of bile induced by ursodeoxycholate

Previous studies demonstrated that higher biliary protein is associated with reduced metastability of bile. This study attempted to examine the induced effect of ursodeoxycholate on metastability of bile by measuring the nucleation time and biliary protein in cholesterol gallstone patients. Thirty-seven patients with functioning gallbladders were studied 10 control patients without gallstones and 27 with cholesterol gallstones. Ten of 27 cholesterol gallstone patients were treated with ursodeoxycholate (600 mg/ day) prior to surgery. Twelve of 17 untreated gallstone patients had cholesterol crystals in gallbladder bile while cholesterol crystals were absent in the ursodeoxycholate-treated gallstone patients and in the controls. Total protein concentration and cholesterol saturation index were significantly greater in the untreated gallstone patients with crystals than in those without crystals in bile. The treatment with ursodeoxycholate significantly decreased biliary protein concentration and cholesterol saturation index associated with the prolonged nucleation time. Cholesterol nucleation time correlated with biliary total protein concentration and cholesterol saturation index but not with total lipid concentration. It is concluded from the present study that ursodeoxycholate decreases biliary protein thereby partly increasing metastability of gallbladder bile.     

Stimulation of Gallbladder by Intravenous Infusion of Amino Acid: A New Method to Obtain Duodenal Bile for Bile Analyses

Bile analysis is performed on duodenal bile obtained after stimulation of the gallbladder (GB) with cholecystokinin or its analog. Rapid amino acids (AA) infusion contracts the GB. Our objective was to assess qualitatively the adequacy of duodenal bile obtained following AA infusion. We prospectively studied 15 patients each with non ulcer dyspepsia (NUD) and gallstones (GS), and 17 patients with acute idiopathic pancreatitis (AIP). Duodenal bile was obtained after duodenal intubation and stimulation of GB by rapid AA infusion. The GB contractile response to AA infusion was assessed by functional ultrasonography. Bile was analyzed for lipids, nucleation time, cholesterol saturation index (CSI), and biliary crystals. Adequate duodenal bile could be collected in all but one patient with AIP and one with GS. The mean ± sd percent ejection fraction of GB following AA infusion in patients with NUD, GS and AIP was 53.41 ± 16.23, 52.06 ± 16.07, and 43.37 ± 14.16, respectively. Biliary microscopy showed the presence of cholesterol monohydrate crystals (CMC) in 7 of 16 patients with AIP, 12 of 14 patients with GS, and 1 of 15 patients with NUD. Mean CSIs in patients with NUD, GS, CMC-positive AIP, and CMC-negative AIP were 0.78, 1.97, 1.85, and 1.00, respectively. Nucleation time in patients with NUD and gallstones was 21.1 and 8.42 days, respectively. In conclusion, qualitatively adequate bile can be obtained for chemical and microscopic examination following rapid intravenous infusion of AA to stimulate the GB.     

Effect of gallbladder mucin on the crystallization of cholesterol in bile

OBJECTIVES: Mucin is supposed to accelerate the crystallization of cholesterol in model bile while studies in native human gallbladder bile revealed conflicting results. METHODS: Therefore, we determined the relation of mucin concentration and cholesterol crystal observation time in gallbladder bile of 73 patients with cholesterol and mixed and 21 patients with pigment stones. In addition, bile samples of 20 patients with cholesterol gallstones were supplemented with either 0 (control) or 0.5-4.0 mg/ml purified bovine mucin or human mucin isolated from gallbladder bile, to study the effect of variable mucin concentrations on the crystallization of cholesterol. RESULTS: Rapid nucleating biles ( 4 days, n = 35) cholesterol crystal observation times (P < 0.05), but no correlation between mucin concentration and cholesterol crystal observation time was observed. Supplementation experiments with bovine purified mucin (up to 4.0 mg/ml) showed no significant effect on the total amount of newly formed cholesterol crystals within 21 days. However, higher amounts of newly formed cholesterol crystals were seen in bile samples supplemented with human mucin in comparison to negative controls. CONCLUSIONS: Our results demonstrate a dose-dependent effect of human but not of bovine gallbladder mucin on the formation of cholesterol monohydrate crystals in gallbladder bile of patients with cholesterol stones. Therefore, studies of cholesterol crystallization in model bile systems may be valuable but should always be confirmed in native gallbladder bile as the more physiological effector system.