Biliary sludge is formed by modification of hepatic bile by the gallbladder mucosa

Effects of Biliary Phospholipids on Cholesterol Crystallization and Growth in Gallstone Formation

The prevalence of cholesterol gallstone disease is increasing, primarily due to the global epidemic of obesity associated with insulin resistance, and this trend leads to a considerable healthcare, financial, and social burden worldwide. Although phospholipids play an essential role in maintaining cholesterol solubility in bile through both mixed micelles and vesicles, little attention has been paid to the impact of biliary phospholipids on the pathogenesis of cholesterol gallstone formation. A reduction or deficiency of biliary phospholipids results in a distinctly abnormal metastable physical-chemical state of bile predisposing to supersaturation with cholesterol. Changes in biliary phospholipid concentrations influence cholesterol crystallization by yielding both liquid crystalline and "anhydrous" crystalline metastable intermediates, evolving into classical parallelogram-shaped cholesterol monohydrate crystals in supersaturated bile. As a result, five distinct crystallization pathways, A-E, have been defined, mainly based on the prime habits of liquid and solid crystals in the physiological or pathophysiological cholesterol saturation of gallbladder and hepatic bile. This review concisely summarizes the chemical structures and physical-chemical properties of biliary phospholipids and their physiological functions in bile formation and cholesterol solubility in bile, as well as comprehensively discusses the latest advances in the role of biliary phospholipids in cholesterol crystallization and growth in gallstone formation, largely based on the findings from clinical and animal studies and in vitro experiments. The insights gleaned from uncovering the cholelithogenic mechanisms are expected to form a fundamental framework for investigating the hitherto elusive events in the earliest stage of cholesterol nucleation and crystallization. This may help to identify better measures for early diagnosis and prevention in susceptible subjects and effective treatment of patients with gallstones.

Free fatty acids and triglyceride change in the gallbladder bile of gallstone patients with pancreaticobiliary reflux

Background

Pancreaticobiliary reflux (PBR) causes chronic inflammation of the gallbladder mucosa and changes in the bile components, which are known to promote gallstone formation. This study aimed to investigate the bile biochemistry changes in gallstone patients with PBR and provide new clues for research on the involvement of PBR in gallstone formation.

Methods

Patients undergoing surgery for gallstones between December 2020 and May 2021 were eligible for inclusion. The bile biochemistry (including amylase, lipase, triglyceride, cholesterol, free fatty acids [FFAs], alanine aminotransferase [ALT], aspartate aminotransferase [AST], alkaline phosphatase [ALP], and γ-glutamyl transferase [γ-GT]) of the included gallstone patients was analysed to determine correlations with PBR.

Results

In this study, 144 gallstone patients who underwent surgery were enrolled. Overall, 15.97 % of the patients had an increased bile amylase level, which was associated with older age and significantly higher bile levels of ALP, lipase, triglyceride, and FFAs. Positive correlations were observed between amylase and lipase, triglyceride, FFAs levels in the gallbladder bile. However, the bile levels of triglyceride, FFAs, and lipase were positively correlated with each other only in the PBR group and showed no significant correlation in the control (N) group. In addition, elevated bile FFAs levels were found to be an independent risk factor for gallbladder wall thickening.

Conclusions

In conclusion, PBR-induced increase in FFAs and triglyceride in the gallbladder bile is a cause of gallstone formation, and an increase in bile ALP suggests the presence of cholestasis in PBR.

Biliary adverse events in acromegaly during somatostatin receptor ligands: predictors of onset and response to ursodeoxycholic acid treatment

PURPOSE

Somatostatin receptor ligands (SRL) are the first-line medical treatment for acromegaly. Gallbladder alterations are one of most important SRL side effect, but according to some authors growth hormone hypersecretion itself is a risk factor for gallstones. This single center, longitudinal retrospective study evaluated the incidence and the predictors of biliary adverse events (BAE) in acromegaly during SRL therapy and their response to ursodeoxycholic acid (UDCA).

METHODS

91 acromegaly patients with indication to SRL were enrolled. Evaluations of acromegaly activity (GH, IGF-I, IGF-I/ULN) and metabolic profile were collected before starting treatment, yearly during follow-up and at BAE onset. In patients developing BAE we searched for predictors of UDCA effectiveness.

RESULTS

61.5% of patients developed BAE (58.9% cholelithiasis; 41.1% only sludge). IGF-I and IGF-I/ULN proved to be positive predictor of BAE, which occur about 5 years after SRL starting. None of metabolic markers proved to be associated with BAE. Only five patients (5.5%) underwent cholecystectomy for symptomatic cholelithiasis. 71% of patients started UDCA treatment, achieving regression of BAE in 60% of cases (88% in patients developing only sludge and 30% in patients affected by cholelithiasis, p < 0.001). BMI and obesity were negative predictors of UDCA efficacy. In 50% of the subjects BAE resolved after 36 months of therapy with a lower rate if cholelithiasis was present.

CONCLUSION

Biliary stone disease is a frequent SRL adverse event, although it is often symptomless. Ultrasound follow-up mainly in the first 5 years of therapy, early UDCA starting and proper lifestyle represent a valid strategy in their detection and management.

Common bile duct pressure in patients with and without cholelithiasis: A case-control study

BACKGROUND

The reflux of pancreatic enzymes into the bile duct and the gallbladder is an abnormal phenomenon that plays a role in lithogenesis and carcinogenesis. Because the pressure of the common bile duct depends on the pressures of the sphincter of Oddi, its dysfunction would be reflected in an increase in the pressure of the common bile duct in patients with cholelithiasis. The objective of this study was to measure the pressures of the common bile duct in patients with and without cholelithiasis and to relate them to the presence of pancreatobiliary reflux.

METHODS

A prospective case-control study was designed. The study universe was constituted by all patients undergoing total gastrectomy for gastric cancer stages I and II over 30 months. The primary outcome measure was to establish differences between common bile duct pressures in patients with and without cholelithiasis.

RESULTS

Common bile duct pressures in patients with gallstones showed a significant elevation (16.9 mmHg) compared to patients without gallstones (3.3 mm Hg) (p < 0.0001). These pressures correlated with the levels of amylase and lipase in gallbladder bile; higher levels were found in patients with gallstones compared to patients without gallstones (P < 0.0001).

CONCLUSIONS

Common bile duct pressure in patients with cholelithiasis was significantly higher compared to patients without cholelithiasis leading to pancreatobiliary reflux.

EUS is superior to secretin-enhanced cholangio-MRI to establish the etiology of idiopathic acute pancreatitis

Background and study aims  The etiology of idiopathic acute pancreatitis (IAP) should always be defined. Our aim was to compare the diagnostic value of endoscopic ultrasound (EUS) versus secretin-enhanced magnetic resonance cholangiopancreatography (S-MRCP) in patients with IAP. Patients and Methods  Patients admitted to a single tertiary care University hospital with IAP were invited to participate in the study. Enrolled patients underwent EUS and S-MRCP in a single-blinded comparative study. EUS and S-MRCP were performed no sooner than 4 weeks after discharge. The diagnostic yield of EUS and S-MRCP and demographic variables were included in the analysis. Additional follow-up, results of subsequent serology, radiographic exams, and relevant histological analysis were considered in determination of the final diagnosis. Results  A total of 34 patients were enrolled; EUS was normal in six, cholelithiasis was defined in 15, choledocholithiasis in two, pancreas divisum in three, branch-type intraductal papillary mucinous tumor (IPMT) in three, and chronic pancreatitis in five. S-MRCP identified choledocholithiasis in one, divisum in four, branch-type IPMT in three, chronic pancreatitis in two; 24 subjects diagnosed as normal by S-MRCP. Diagnostic correlation between EUS and S-MRCP was slight (kappa = 0.236, 95 % confidence interval: 0.055-0.416). EUS provided a statistically significantly higher diagnostic yield than S-MRCP: 79.4 % (CI95 %: 65 %-94 %) vs 29.4 % (CI95 %: 13 %-46 %) (P = 0.0002). The sensitivity, specificity, and positive and negative predictive values of EUS and S-MRCP were 90 %, 80 %, 96 %, 57 % and 33 %, 100 %, 100 % and 16 %, respectively. Conclusion  The diagnostic yield of EUS is higher than S-MRCP in patients with IAP.

Similarities and differences between biliary sludge and microlithiasis: Their clinical and pathophysiological significances

The terms biliary sludge and cholesterol microlithiasis (hereafter referred to as microlithiasis) were originated from different diagnostic techniques and may represent different stages of cholesterol gallstone disease. Although the pathogenesis of biliary sludge and microlithiasis may be similar, microlithiasis could be preceded by biliary sludge, followed by persistent precipitation and aggregation of solid cholesterol crystals, and eventually, gallstone formation. Many clinical conditions are clearly associated with the formation of biliary sludge and microlithiasis, including total parenteral nutrition, rapid weight loss, pregnancy, organ transplantation, administration of certain medications, and a variety of acute and chronic illnesses. Numerous studies have demonstrated complete resolution of biliary sludge in approximately 40% of patients, a cyclic pattern of disappearing and reappearing in about 40%, and progression to gallstones in nearly 20%. Although only a minority of patients with ultrasonographic demonstration of biliary sludge develop gallstones, it is still a matter of controversy whether microlithiasis could eventually evolve to cholesterol gallstones. Biliary sludge and microlithiasis are asymptomatic in the vast majority of patients; however, they can cause biliary colic, acute cholecystitis, and acute pancreatitis. Biliary sludge and microlithiasis are most often diagnosed ultrasonographically and bile microscopy is considered the gold standard for their diagnosis. Specific measures to prevent the development of biliary sludge are not practical or cost-effective in the general population. Laparoscopic cholecystectomy offers the most definitive therapy on biliary sludge. Endoscopic sphincterotomy or surgical intervention is effective for microlithiasis-induced pancreatitis. Ursodeoxycholic acid can effectively prevent the recurrence of solid cholesterol crystals and significantly reduce the risk of recurrent pancreatitis.

Complication Follow-up With Ultrasonographic Analyses of 91 Cases With Donor Gallbladder Preservation in Living Donor Liver Transplantation of Left Lateral Sectionectomies

BACKGROUND

Preserving the donor's gallbladder during living donor liver transplantation (LDLT) is a better method for liver transplantation surgery, but not enough is known about gallbladder complications after the operation.

METHODS

We retrospectively investigated postsurgical donor gallbladder complications in clinical LDLT with gallbladder preservation. The feasibility of retaining the gallbladder during liver graft procurement is discussed. Ninety-one donors with retained gallbladder after LDLT with the hepatic left lateral sectionectomy (from June 2013 to October 2015) were retrospectively analyzed. Donors were followed for 12.6 to 40.7 months after surgery (median 26.1 months). Sonography was used to evaluate gallbladder characteristics before and after surgery.

RESULTS

Gallbladder function had recovered to almost normal 1 month after transplantation. Four donors (4.40%) experienced gallbladder enlargement that resolved after 3 days. Thickening of the gallbladder wall in 31 donors (34.07%) was restored within 2 to 75 days. Biliary sludge appeared in 9 donors (9.89%); 6 of them recovered within 3 to 34 days. Three (3.30%) and 1 donor (1.10%) suffered gallstone and gallbladder polyps, respectively, which persisted until the last follow-up.

CONCLUSION

The rate of postoperative complications of the gallbladder in donors was relative low. Preserving the gallbladder in liver transplantation donors during liver graft procurement is feasible and safe.

Endoscopic Sphincterotomy for Gallbladder Muddy Stones or Sludge in Patients With Papillary Disease: A Retrospective Study

BACKGROUND

The formation of gallbladder stones is associated with dysfunctional contraction and duodenal papilla diseases. However, endoscopic sphincterotomy can improve the contraction of the gallbladder and resolve duodenal papilla disease.

AIM

The aim of the study was to assess the feasibility and effectiveness of endoscopic sphincterotomy in the treatment of muddy stones or sludge in the gallbladder during papillary disease.

METHODS

The clinical data of 53 patients with gallbladder muddy stones or sludge undergoing endoscopic sphincterotomy were retrospectively analyzed.

RESULTS

A total of 53 patients received successful endoscopic sphincterotomy with no serious complications. Sphincterotomy did not significantly lower resting gallbladder volume from 63.2±10.8 to 50.1±5.9 mL (P>0.05), but significantly increased gallbladder ejection fraction from 0.41±0.13 to 0.63±0.16 (P<0.01), as measured by the lipoid food test. The static liver and gallbladder imaging examination also showed an increase in gallbladder ejection fraction from 0.45±0.08 to 0.68±0.11 (P<0.01). In addition, the choledochus pressure reduced from 21.9±4.0 to 15.6±2.5 mm Hg, and the gallbladder muddy stones or sludge disappeared after endoscopic sphincterotomy. At the end of the follow-up period, there was no relapse of sludge or muddy stones in the gallbladder.

CONCLUSIONS

The formation of gallbladder muddy stones or sludge is associated with papilla disease. Endoscopic sphincterotomy can resolve papilla disease, decrease gallbladder bile stasis, improve gallbladder evacuation, and prevent the formation of gallbladder stones.

[Nonalcoholic steatohepatitis and biliary sludge in people with metabolic syndrome]

AIM

To determine the incidence of biliary sludge (BS) and to evaluate the clinical efficacy of Chophytol in patients with nonalcoholic steatohepatitis (NASH) and BS in the presence of metabolic syndrome (MS).

SUBJECTS AND METHODS

Clinical laboratory examination was made in 72 patients with NASH in the presence of MS. BS was identified in 52 (72.2%) examinees who were divided in two (study and control) groups. The efficacy of Chophytol of plant origin, prepared from the purified extract of fresh artichoke (Cynara scolymus) leaf juice, which was used at a dose of 3 tablets thrice daily for a month, was evaluated.

RESULTS

The use of Chophytol was established to promote BS elimination in 87% of the patients. This ceased pain syndrome in 87% and dyspeptic manifestations in 65.2% and normalized the levels of lipids and the biochemical indicators of liver process activity. No adverse drug reactions were seen.

CONCLUSION

Chophytol used in patients with HASH and BS may soon be possible to make general condition better, to alleviate the symptoms of diseases of the liver and biliary system, and to appreciably improve the biochemical indicators of blood and bile.

Spectral and morphological classification of different chronic and acute Taiwanese gallstones via FTIR, SEM and ESEM-EDX microanalyses

BACKGROUND

Gallstone disease is one of the leading upper gastrointestinal surgical problems in different countries.

AIMS

To analyze the chronic gallstones and acute gallbladder sludge retrieved from 36 Taiwanese patients.

METHODS

FTIR microspectroscopy was used to classify the types of gallstones, and an ESEM-EDX microanalysis was first applied to determine the microstructural features and elemental compositions of the various gallstones. Bacteria presented on the surface of gallstones were also detected by SEM.

RESULTS

Four types of gallstones were obtained from these 36 Taiwanese patients: calcium bilirubinate (CaBR) stones (30.6%), cholesterol stones (19.4%), mixed stones including 6 subtypes (47.2%), and acute gallbladder sludge (2.8%) made of CaBR and protein/insoluble biomaterials. Bacteria imprints and bacterial discharges or bacterial biofilms were also found on the surface of gallstones and acute sludge under a SEM observation. ESEM-EDX results revealed that calcium was found to be the main constituent of all of the types of stones except cholesterol stones, and aluminum was also presented in most of the stones and sludge samples. Chloride was only detected in the acute gallbladder sludge.

CONCLUSION

FTIR spectra, morphological features, and elemental compositions of the acute gallbladder sludge were different from those of the chronic gallstones.

Clinical Importance and Natural History of Biliary Sludge in Outpatients

OBJECTIVES

Gallbladder sludge is a common diagnosis on routine abdominal sonography, yet its clinical importance is uncertain, especially in outpatients. To determine its natural history and potential future complications in this setting, we reviewed the imaging and clinical histories of nonhospitalized patients with a diagnosis of sludge on sonography.

METHODS

We conducted a retrospective search of our institutional radiology information system for all sonographic reports using the key words "biliary sludge without gallstones" over a 3-year period. For each of the 104 patients with isolated biliary sludge on initial sonography, we reviewed the electronic medical records and all imaging for the development of pancreaticobiliary complications.

RESULTS

We found an overall prevalence of biliary sludge in outpatients of 1.8%. Of the 104 patients reviewed with a mean follow up of 630 days (21 months), 25 developed a pancreaticobiliary complication, including cholelithiasis, cholecystitis, choledocholithiasis, and pancreatitis. The most frequent complication was cholecystitis, with a total of 14 diagnoses (12 chronic acalculous and 2 acute with gallstones). An additional 6 patients developed gallstones without cholecystitis features; 4 patients developed pancreatitis; and 1 developed choledocholithiasis. Biliary sludge remained quiescent or resolved in 76% of patients.

CONCLUSIONS

Biliary sludge always represents a pathologic process, but its clinical implications among outpatients have not been previously investigated. Our ambulatory population developed pancreaticobiliary complications at similar rates as prior mixed-patient setting studies. Regardless of the patient setting, biliary sludge is likely of more clinical importance than previously regarded.

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.

The gallbladder of the electric ray Torpedo marmorata Risso displays excrescent cholecystocytes with merocrine and apocrine-like secretions

The gallbladder of Torpedo marmorata exhibits a mucosal surface layer of simple columnar epithelium with very tall cholecystocytes. The apical domain of each cell has few microvilli, but many mucous vesicles that are secreted by exocytosis at the cell apices. The apical regions may also elongate and undergo self-excision while shedding mucus and cell debris into the gallbladder lumen in a manner similar to that described in mammals as a result of sex steroid treatment to induce gallstones and to that found in the cholecystitis associated with cholelithiasis. Numerous small mitochondria, spherical to elongated, are distributed throughout the cells, while the nuclei are often located in the lower third of each cell. In the lower part of the cholecystocytes, large and very densely contrasted lysosomes can be found. All cells are tightly joined by junctional complexes, including long, highly contrasted desmosomes. The fibromuscular layer is made of a loose stroma with a limited muscular component and a poor blood supply. Large diameter blood vessels can only be found in the subserosal layer. It is hypothesized that the obligatorily carnivorous diet of this ureotelic fish has resulted in the evolution of a gallbladder ultrastructure resembling that found in cholecystitis but without the associated cholelithiasis.

Many faces of pancreaticobiliary reflux

Pancreaticobiliary reflux may occur either as a result of an anatomically abnormal pancreaticobiliary junction or because of a functionally impaired sphincter despite a normal radiological appearance. It is associated with a wide spectrum of biliary diseases, including gall bladder and bile duct carcinoma. Pancreaticobiliary maljunction and related biliary reflux have been studied extensively in Southeast Asian populations and associations with choledochal cyst and biliary malignancy defined. However, reflux in the absence of ductal malunion has only been described relatively recently and its significance with respect to biliary malignancy requires clarification. We present four cases of pancreaticobiliary reflux to demonstrate the varied associations of this under-recognized disorder and review the related management issues.

Tiny cystine stones in the gallbladder of a patient with cholecystolithiasis complicating acute cholecystitis: a case report

Cystine stones, the main component of which is cystine, are very common urinary calculi, but are rare in the gall bladder. In animals, there has been only one report of cystine gallstones in tree shrews, and to our knowledge, this is the first report of cystine gallstones in humans.

Current knowledge on pancreaticobiliary reflux in normal pancreaticobiliary junction

Knowledge on pancreaticobiliary reflux in normal pancreaticobiliary junction and their pathologic implications has experienced tremendous progress during the last few years. This article reviews the current knowledge on this condition and its pathological implications on gallbladder diseases. Many publications with different levels of evidence were found supporting biliary carcinogenesis associated with pancreaticobiliary reflux in normal and abnormal pancreaticobiliary junction. Also, there are many publications supporting the common occurrence of pancreaticobiliary reflux in normal pancreaticobiliary junction, and sphincter of Oddi dysfunction as the most plausible cause of this condition. Although an important body of research has been published regarding pancreaticobiliary reflux in normal pancreaticobiliary junction and their clinical significance, the current evidence does not fully support what has been suggested. The reflux of pancreatic enzymes into the bile tract and gallbladder is a fascinating subject of study which is open to active research. The final demonstration of the pathophysiology and consequences of PBR in NPBL and support by evidence level type I would constitute a major breakthrough in the understanding and eventually in the treatment of gallbladder diseases.

Endoscopically obtained bile aspirate is an accurate adjunct in the diagnosis of symptomatic gallbladder disease

Endoscopically obtained bile aspirate was found to be an effective technique to identify patients with symptomatic gallbladder disease and negative diagnostic studies.

Objectives:

The experience of a single surgeon in a rural hospital over a 10-year period was analyzed with respect to the utilization of endoscopically obtained bile aspirates as an adjunct in the diagnosis of symptomatic gallbladder disease.

Methods:

A retrospective study of the author's entire cholecystectomy experience over a 10-year period with 641 patients was conducted to evaluate the utility of the bile aspirate in the preoperative selection of operative candidates and with respect to the ultimate pathologic diagnostic accuracy of the test.

Results:

Derivation of preoperative diagnosis via traditional standard means was possible in 479 patients. An endoscopically obtained positive bile aspirate was found in 162 additional patients who failed to have positive traditional diagnostic studies (acalculous gallbladder disease). Micro-pathology was determined to be present in 603 patients (94.07%). In 27 of the 38 negatives, there had been positive radiological studies (71%). In 11 of the 38, a positive preoperative bile aspirate had been obtained (28.9%). Of the 162 patients with a positive bile aspirate, 151 (93.21%) of the gallbladder specimens had confirmatory histologic analysis (92.1% confidence interval ± 3.95%).

Conclusion:

In patients with symptoms suggestive of clinical gallbladder disease and negative traditional diagnostic studies, the endoscopically obtained bile aspirate has been shown to be a highly reliable tool in establishing the diagnosis and is recommended as an aid in the appropriate selection of candidates who may benefit from cholecystectomy.

Pancreaticobiliary reflux in patients with a normal pancreaticobiliary junction: Pathologic implications

Knowledge on pancreaticobiliary reflux in normal pancreaticobiliary junction and its pathologic implications has experienced tremendous progress during the last few years. This editorial reviews the current knowledge on this condition and its pathological implications on gallbladder diseases. The following aspects were defined appropriate for discussion: (1) Evidence of carcinogenesis associated with pancreaticobiliary reflux; (2) Evidence of pancreaticobiliary reflux in normal pancreaticobiliary junction; and (3) Evidence of sphincter of Oddi (SO) dysfunction as a cause of pancreaticobiliary reflux in normal pancreaticobiliary junction. The articles reviewed were selected and classified according to five levels of evidence: LevelI, meta-analysis double-blind randomized clinical trials, Level II, cohort non-blinded studies and non-randomized clinical trials, Level III, good quality case-control studies and non-randomized cohort studies, Level IV, case series and poor quality case-control studies, and Level V, case report articles and experts’ opinion. Evidence levels II, III, IV and V were found to support biliary carcinogenesis associated with pancreaticobiliary reflux in normal and abnormal pancreaticobiliary junction. The same levels of evidence were found to support the common occurrence of pancreaticobiliary reflux in normal pancreaticobiliary junction, and SO dysfunction as the most plausible cause of this condition. Although an important body of research has been published regarding pancreaticobiliary reflux in normal pancreaticobiliary junction and its clinical significance, the current evidence does not fully support what has been suggested. Studies with evidence level I have not been undertaken. This is a fascinating subject of study, and if finally supported by evidence level I, the importance of this condition will constitute a major breakthrough in biliary pathology.

Effect of gallbladder hypomotility on cholesterol crystallization and growth in CCK-deficient mice

We investigated the effect of gallbladder hypomotility on cholesterol crystallization and growth during the early stage of gallstone formation in CCK knockout mice. Contrary to wild-type mice, fasting gallbladder volumes were enlarged and the response of gallbladder emptying to a high-fat meal was impaired in knockout mice on chow or the lithogenic diet. In the lithogenic state, large amounts of mucin gel and liquid crystals as well as arc-like and tubular crystals formed first, followed by rapid formation of classic parallelogram-shaped cholesterol monohydrate crystals in knockout mice. Furthermore, three patterns of crystal growth habits were observed: proportional enlargement, spiral dislocation growth, and twin crystal growth, all enlarging solid cholesterol crystals. At day 15 on the lithogenic diet, 75% of knockout mice formed gallstones. However, wild-type mice formed very little mucin gel, liquid, and solid crystals, and gallstones were not observed. We conclude that lack of CCK induces gallbladder hypomotility that prolongs the residence time of excess cholesterol in the gallbladder, leading to rapid crystallization and precipitation of solid cholesterol crystals. Moreover, during the early stage of gallstone formation, there are two pathways of liquid and polymorph anhydrous crystals evolving to monohydrate crystals and three modes for cholesterol crystal growth.

Mucin gene expression in bile of patients with and without gallstone disease, collected by endoscopic retrograde cholangiography

AIM: To investigate the pattern of mucin expression and concentration in bile obtained during endoscopic retrograde cholangiography (ERC) in relation to gallstone disease.

METHODS: Bile samples obtained at ERC from 29 consecutive patients, 17 with and 12 without gallstone disease were evaluated for mucin content by gel filtration on a Sepharose CL-4B column. Dot blot analysis for bile mucin apoproteins was performed with antibodies to Mucin 1 (MUC1), MUC2, MUC3, MUC5AC, MUC5B and MUC6. Staining intensity score (0-3) was used as a measure of antigen expression.

RESULTS: MUC1, MUC2, MUC3, MUC5AC, MUC5B and MUC6 were demonstrated in 34.4%, 34.4%, 51.7%, 51.7%, 55.1% and 27.5% of bile samples, respectively. The staining intensity scores were 0.62 ± 0.94, 0.58 ± 0.90, 0.79 ± 0.97, 1.06 ± 1.22, 1.20 ± 1.26 and 0.41 ± 0.73, respectively. Mean mucin concentration measured in bile by the Sepharose CL-4B method was 22.8 ± 24.0 mg/mL (range 3.4-89.0 mg/mL). Mean protein concentration was 8.1 ± 4.8 mg/mL (range 1.7-23.2 mg/mL).

CONCLUSION: High levels of MUC3, MUC5AC and MUC5B are expressed in bile aspirated during ERC examination. A specific pattern of mucin gene expression or change in mucin concentration was not found in gallstone disease.

Physical chemistry of intestinal absorption of biliary cholesterol in mice

Although many putative sterol transporters influencing cholesterol absorption and physical-chemical factors affecting dietary cholesterol absorption have been extensively investigated, it is still unclear how biliary cholesterol contributes to the regulation of intestinal cholesterol absorption. We studied whether the gallbladder can modulate the microaggregates of cholesterol carriers, which may in turn influence the intestinal absorption of biliary cholesterol. Supersaturated, crystallized, or micellar model biles were delivered via a duodenal catheter to conscious, freely moving C57L mice daily for 2 days. Intestinal uptake and absorption of biliary cholesterol and its fecal excretion, as well as expression levels of intestinal sterol transporters, were analyzed. Cholesterol uptake and absorption by the enterocyte were dramatically reduced in mice treated with crystallized biles compared with supersaturated biles. This correlated with the higher cumulative radioactivity of cholesterol recovered in the feces at 24 hours. Such findings were absent with the added reference compound sitostanol. After removing cholesterol crystals from crystallized biles, micellar biles showed essentially identical effects on intestinal absorption but with lower fecal cholesterol excretion compared with the original samples containing crystals. Expression levels of the jejunal Abcg5 (ATP-binding cassette transporter G5) and Abcg8, but not Npc1l1 (Niemann-Pick C1 like 1), were significantly increased by supersaturated biles compared with crystallized biles.

CONCLUSION

Different physical forms of biliary cholesterol dramatically determine intestinal uptake and absorption of cholesterol. Solid plate-like cholesterol monohydrate crystals in bile are probably not absorbed and are totally excreted in feces from the body. The gallbladder may have a role in regulating cholesterol homeostasis by modulating the physical forms of biliary cholesterol.

A comparative study of microstructural development in paired human hepatic and gallbladder biles

Cholesterol gallstones usually develop in the gallbladder and rarely form in bile ducts even in patients with highly lithogenic bile. Bile concentration and proteins (e.g. mucin) may affect crystallization, but the exact nature of this effect, especially in relation to crystallization pathways and microstructural evolution remains unclear. We examined lipid microstructures in paired hepatic and gallbladder biles to reveal ones that are essential for crystallization. Combining digital light microscopy with cryogenic-temperature transmission electron microscopy we are able to directly visualize and compare the time evolution of lipid microstructures in paired hepatic, gallbladder and diluted gallbladder biles of gallstone patients and controls, without drying or separating. Gallbladder bile exhibited several multilamellar vesicles and spheroidal micelles preceding and throughout crystallization. Vesicle morphology changed before crystallization was observed. In contrast, hepatic bile revealed almost no crystallization and while a variety of unilamellar vesicles and spheroidal micelles existed throughout the examination, multilamellar vesicles were rare. Diluted gallbladder bile was different from native gallbladder bile, as well as the paired hepatic bile, yielding occasional crystallization. Our findings suggest that maturing multilamellar vesicles precede (and at least partially initiate) crystallization in gallbladder bile. Although microstructural development seems to be concentration dependent, dilution of gallbladder bile to hepatic bile concentrations neither makes it identical to hepatic bile, nor prevents crystallization.

Gallbladder disease in Shetland Sheepdogs: 38 cases (1995-2005)

OBJECTIVE

To determine risk, clinical features, and treatment responses for gallbladder disorders in Shetland Sheepdogs.

DESIGN

Retrospective case-control study.

ANIMALS

38 Shetland Sheepdogs with gallbladder disease.

PROCEDURES

Medical records were reviewed for signalment, history, physical findings, laboratory results, imaging features, coexistent illnesses, histologic findings, treatments, and survival rates.

RESULTS

Mature dogs with gastrointestinal signs were predisposed (odds ratio, 7.2) to gallbladder disorders. Gallbladder mucocele was confirmed in 25 dogs. Concurrent problems included pancreatitis, hyperlipidemia, corticosteroid excess, hypothyroidism, protein-losing nephropathy, diabetes mellitus, cholelithiasis, and gallbladder dysmotility. Mortality rate was 68% with and 32% without bile peritonitis. Nonsurvivors had high WBC and neutrophil count and low potassium concentration. Although preprandial hypercholesterolemia, hypertriglyceridemia, and high serum liver enzyme activities were common, gallbladder disease was serendipitously discovered in 11 of 38 dogs. Histologic examination (n=20 dogs) revealed gallbladder cystic mucosal hyperplasia in 20 dogs, cholecystitis in 16, periportal hepatitis in 9, and vacuolar hepatopathy in 7. Surgery included cholecystectomy (n=17) and cholecystoenterostomy (4). In 1 hyperlipidemic dog without clinical signs, gallbladder mucocele resolved 6 months after beginning use of a fat-restricted diet and ursodeoxycholic acid.

CONCLUSIONS AND CLINICAL RELEVANCE

Shetland Sheepdogs are predisposed to gallbladder disorders, with mucoceles and concurrent dyslipidemia or dysmotility in many affected dogs. Most dogs were without clinical signs during mucocele development. Low survival rate after cholecystectomy in clinically affected dogs suggested that preemptive surgical interventions may be a more appropriate treatment strategy.

Occult pancreaticobiliary reflux in gallbladder cancer and benign gallbladder diseases

BACKGROUND AND OBJECTIVES

It was proposed that occult pancreaticobiliary reflux (OPBR) was associated with precancerous mucosal changes in the gallbladder, hence the importance of this disorder. There are no published reports investigating the incidence of OPBR in patients operated on for the entire spectrum of benign gallbladder diseases and gallbladder cancer. Our aim was to determine the incidence of OPBR and measure the levels of active pancreatic enzymes (amylase and lipase) in gallbladder bile of patients undergoing cholecystectomy for benign and malignant gallbladder diseases.

METHODS

One hundred eight patients with normal pancreaticobiliary junction evidenced by operative cholangiography were included in the study.

RESULTS

According to gallbladder bile amylase and lipase levels, 84.2% and 89% patients respectively had OPBR. OPBR was present in all gallbladder cancer patients; in these patients the biliary levels of amylase and lipase were significantly higher than the levels found in patients with benign gallbladder pathology (P < 0.0001).

CONCLUSIONS

OPBR could lead to inflammatory changes of the biliary epithelium and progress towards the development of precancerous mucosal changes and gallbladder cancer. The reason why such high levels of pancreatic enzymes are regurgitated into the biliary tree of patients with gallbladder cancer should be clarified.

Gallstone disease

Gallstone disease is one of the most prevalent gastrointestinal diseases with a substantial burden to health care systems that is supposed to increase in ageing populations at risk. Aetiology and pathogenesis of cholesterol gallstones still are not well defined, and strategies for prevention and efficient nonsurgical therapies are missing. This review summarizes current concepts on the pathogenesis of cholesterol gallstones with focus on the uptake and secretion of biliary lipids and special emphasis on recent studies into the genetic background.

Gallstone disease: Epidemiology of gallbladder stone disease

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