The role of bacteria in gallstone pathogenesis

Clinical features, concurrent disorders, and survival time in cats with suppurative cholangitis-cholangiohepatitis syndrome

OBJECTIVE

To characterize clinical features, comorbidities, frequency of bacterial isolation, and survival time in cats with suppurative cholangitis-cholangiohepatitis syndrome (S-CCHS).

ANIMALS

168 client-owned cats with S-CCHS.

PROCEDURES

Data were prospectively (1980 to 2019) collected regarding clinical features, comorbidities, bacterial infection, illness duration, and treatments. Variables were evaluated for associations with survival time.

RESULTS

Median age of cats was 10.0 years, with no breed or sex predilection observed. Common clinical features included hyporexia (82%), hyperbilirubinemia (80%), lethargy (80%), vomiting (80%), jaundice (67%), weight loss (54%), and hypoalbuminemia (50%). Comorbidities included extrahepatic bile duct obstruction (53%), cholelithiasis (42%), cholecystitis (40%), and ductal plate malformation (44%) as well as biopsy-confirmed inflammatory bowel disease (60/68 [88%]) and pancreatitis (41/44 [93%]). Bacterial cultures were commonly positive (69%) despite prebiopsy antimicrobial administration in most cats. Of surgically confirmed choleliths, diagnostic imaging identified only 58%. Among 55 cats with "idiopathic pancreatitis," 28 (51%) were documented to have transiting choleliths, and 20 had pancreatic biopsies confirming pancreatitis. Cholelithiasis (with or without bile duct obstruction) and cholecystectomy were associated with survival advantages. Survival disadvantages were found for leukocytosis, ≥ 2-fold increased alkaline phosphatase, and hyperbilirubinemia. Cholecystoenterostomy had no survival impact. Cats with ductal plate malformations were significantly younger at diagnosis and death than other cats. Chronic treatments with antimicrobials, S-adenosylmethionine, and ursodeoxycholic acid were common postbiopsy.

CLINICAL RELEVANCE

S-CCHS in cats was associated with bacterial infection and various comorbidities and may be confused with pancreatitis. Surgically correctable morbidities (ie, cholecystitis, cholecystocholelithiasis) and cholecystectomy provided a significant survival advantage.

Antiquorum sensing and antibiofilm potential of biosynthesized silver nanoparticles of Myristica fragrans seed extract against MDR Salmonella enterica serovar Typhi isolates from asymptomatic typhoid carriers and typhoid patients

Globally, Salmonella infection poses a major public health problem. Here, we report antibiofilm activity and quorum sensing inhibition of aqueous seeds extract of Myristica fragrans (nutmeg) and biosynthesized silver nanoparticles (AgNPs) against multidrug resistant (MDR) Salmonella enterica serovar Typhi (S. Typhi) isolated from typhoid patients and asymptomatic carriers. S. Typhi isolates revealed higher percentage (46%) of biofilm production identified by tissue culture plate (TCP) than Congo red agar (CRA) and tube adherence (TA) methods. The inhibition of biofilm-producing MDR S. Typhi isolates and pigment production of Chromobacterium violaceum (indicator bacteria) demonstrated the quorum sensing potential of nutmeg. The aqueous seed extract of nutmeg exhibited 87% of antibiofilm activity, while the biosynthesized AgNPs showed 99.1% of antibiofilm activity. Molecular docking studies of bioactive compounds of nutmeg against transcriptional regulatory protein RcsB and sensor kinase protein RcsC revealed interaction with the target proteins. It is proposed that biosynthesized AgNPs could be used as one of the effective candidates in treating asymptomatic typhoid carriers or typhoid patients and to control the subsistence of biofilm-producing S. Typhi strains or other pathogenic bacteria in the environment or industrial settings.

Genome-wide association meta-analysis yields 20 loci associated with gallstone disease

Gallstones are responsible for one of the most common diseases in the Western world and are commonly treated with cholecystectomy. We perform a meta-analysis of two genome-wide association studies of gallstone disease in Iceland and the UK, totaling 27,174 cases and 736,838 controls, uncovering 21 novel gallstone-associated variants at 20 loci. Two distinct low frequency missense variants in SLC10A2, encoding the apical sodium-dependent bile acid transporter (ASBT), associate with an increased risk of gallstone disease (Pro290Ser: OR = 1.36 [1.25-1.49], P = 2.1 × 10-12, MAF = 1%; Val98Ile: OR = 1.15 [1.10-1.20], P = 1.8 × 10-10, MAF = 4%). We demonstrate that lower bile acid transport by ASBT is accompanied by greater risk of gallstone disease and highlight the role of the intestinal compartment of the enterohepatic circulation of bile acids in gallstone disease susceptibility. Additionally, two low frequency missense variants in SERPINA1 and HNF4A and 17 common variants represent novel associations with gallstone disease.

Metagenomics of pigmented and cholesterol gallstones: the putative role of bacteria

There is growing evidence for bacteria playing a role in the pathogenesis and formation of pigmented gallstones from humans. These studies mainly involved cultivation of gallstone-associated bacteria and 16S rRNA profiling, providing an indirect link between processes involved in gallstone formation by the bacteria in-situ. Here, we provide functional metagenomic evidence of a range of genes involved in bile stress response, biofilm formation, and anaerobic energy metabolism by Gram-negative Klebsiella in pigmented gallstones from a 76-year-old male patient. Klebsiella was also present in one cholesterol-type stone in a 30-year-old female patient who had additional cholesterol gallstones characterised by Gram-positive bacteria. Pigmented stones further revealed a predominance of genes involved in carbohydrate metabolism, whilst cholesterol stones indicated a profile dominanted by protein metabolism possibly reflecting known chemical differences between Gram-negative and Gram-positive biofilm matrices. Archaeal genes were not detected. Complementary carbon and hydrogen isotopic analyses of cholesterol within the patients’ stones revealed homogeneity, suggesting a common diet or cholesterol biosynthesis pathway that has little influence on microbial composition. This pilot study provides a framework to study microbial processes that play a potential role in gallstone formation across markedly different types of stones and patient backgrounds.

Colonization, resistance to bile, and virulence properties of Escherichia coli strains: Unusual characteristics associated with biliary tract diseases

Escherichia coli is the species that is most frequently isolated from bile of patients with biliary tract diseases. This study was aimed to investigate any association between resistance and virulence properties of these isolates with occurrence of the diseases. A total of 102 bile samples were obtained from patients subjected to endoscopic retrograde cholangiopancreatography for different biliary diseases. Clinical data were collected and culture of the bile samples was done on selective media. Resistance of characterized Escherichia coli isolates to deoxycholate sodium (0-7%) and nineteen antibiotics was determined and PCR using 16 pairs of primers targeting stx1, stx2, exhA, eae, bfp, agg, pcvd432, lt, st, ipaH, pic, pet, ast, set, sen, and cdtB genes was done. Our results showed a statistically significant association between E. coli colonization and existence of common bile duct and gallbladder stones (p value 0.028). Out of the 22 E. coli strains (22/102) multidrug resistance phenotype was present in 95.45%. None of the strains belonged to common E. coli pathotypes. However, bfp + EhxA-hly, bfp + astA, bfp + EhxA-hly + pic, and EhxA-hly + pic + astA, bfp, and astA genotypes were detected in these strains. bfp (7/22, 31.8%) and astA (5/22, 22.7%) were among most frequent virulence factors in these strains. Results of this study showed significant association between colonization of E. coli and choledocholithiasis. Unusual existence of virulence gene combinations in these strains and their resistance to DOC and multiple classes of antibiotics could be considered as possible causes of their persistence in this harsh microenvironment.

Surgical treatments for patients with recurrent bile duct stones and Oddis sphincter laxity

Recurrent bile duct stones is the most common complication after gallstone surgery and the incidence is about 4-24%. Sphincter of Oddi laxity will lead to duodenal content flow into the bile or pancreatic duct. Patients with recurrent bile duct stones and Oddis sphincter laxity were intractable. Here we sought to present the possible and helpful surgical treatments for such patients. Prospective randomized clinical trial are needed for evaluating the outcome of surgical treatments.

A case of gallstones in an African green monkey (Chlorocebus aethiops)

Spontaneous cholelithiasis was found in a male African green monkey (Chlorocebus aethiops) at necropsy. Choleliths varied in size, shape and colour. Gallstones were analysed using accepted analytical methods. Results showed that the gallstones were composed of cholesterol and protein in varying proportions. Histologically, the gallbladder showed diffuse mild to moderate lymphocytic infiltration. The etiology of the cholelithiasis in the examined individual remains unknown.

MICROBIOLOGICAL ANALYSIS OF BILE IN PATIENTS WITH BENIGN AND MALIGNANT BILIOPANCREATIC DISEASES AND ITS CONSEQUENCES

BACKGROUND

Bactibilia has several consequences to human health.

OBJETIVE

Assessing the bile microbiology of patients with biliopancreatic diseases in order to identify bacteria and their possible infectious complications.

METHODS

Retrospective study of 30 bile culture samples from patients with benign and malignant biliopancreatic diseases. The samples were assessed to set the bile microbiological flora and to search for its possible link with comorbidity, carcinogenesis and postoperative infectious complications.

RESULTS

Thirty bile samples from patients at mean age ≈57.7 years, mostly female (n=18), were assessed. Bactibilia was found in 12 cases, mostly in patients with benign diseases (n=8), older than 50 years (n=23) and female (n=10). Adenocarcinoma of the duodenal papilla (n=9) and cholelithiasis (n=8) were the most common diseases. Escherichia coli (n=5) and Klebsiella sp (n=3) were predominantly found in patients with benign diseases; and Klebsiella sp (n=2) and Streptococcus sp (n=2) were prevalent in cancer patients. There were postoperative infectious complications in seven cases, five of them in bactibilia-associated patients (P=0.084).

CONCLUSION

Bactibilia was found in 12 samples and Escherichia coli and Klebsiella sp were most often identified in patients with benign diseases, as well as Streptococcus sp and Klebsiella sp in cancer patients. There was a trend of higher postoperative infectious complication incidence in patients with bactibilia.

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.

Metagenomic sequencing of bile from gallstone patients to identify different microbial community patterns and novel biliary bacteria

Despite the high worldwide prevalence of gallstone disease, the role of the biliary microbiota in gallstone pathogenesis remains obscure. Next-generation sequencing offers advantages for systematically understanding the human microbiota; however, there have been few such investigations of the biliary microbiome. Here, we performed whole-metagenome shotgun (WMS) sequencing and 16S rRNA sequencing on bile samples from 15 Chinese patients with gallstone disease. Microbial communities of most individuals were clustered into two types, according to the relative enrichment of different intestinal bacterial species. In the bile samples, oral cavity/respiratory tract inhabitants were more prevalent than intestinal inhabitants and existed in both community types. Unexpectedly, the two types were not associated with fever status or surgical history, and many bacteria were patient-specific. We identified 13 novel biliary bacteria based on WMS sequencing, as well as genes encoding putative proteins related to gallstone formation and bile resistance (e.g., β-glucuronidase and multidrug efflux pumps). Bile samples from gallstone patients had reduced microbial diversity compared to healthy faecal samples. Patient samples were enriched in pathways related to oxidative stress and flagellar assembly, whereas carbohydrate metabolic pathways showed varying behaviours. As the first biliary WMS survey, our study reveals the complexity and specificity of biliary microecology.

Acute cholecystitis associated with infection of Enterobacteriaceae from gut microbiota

Acute cholecystitis (AC) is one of the most common surgical diseases. Bacterial infection accounts for 50% to 85% of the disease's onset. Since there is a close relationship between the biliary system and the gut, the aims of this study were to characterize and determine the influence of gut microbiota on AC, to detect the pathogenic microorganism in the biliary system, and to explore the relationship between the gut and bile microbiota of patients with AC. A total of 185 713 high-quality sequence reads were generated from the faecal samples of 15 patients and 13 healthy controls by 16S rRNA gene pyrosequencing. Patients' samples were significantly enriched in Akkermansia, Enterobacter and Escherichia/Shigella group. The healthy controls, however, showed significant enrichment of Clostridiales, Coprococcus, Coprobacillaceae, Paraprevotella, Turicibacter and TM7-3 in their faecal samples. Escherichia coli was the main biliary pathogenic microorganism, among others such as Klebsiella spp., Clostridium perfringens, Citrobacter freundii and Enterobacter cloacae in the bile of the patients. Additionally, the amount of bile endotoxin significantly correlated with the number of Enterobacteriaceae, especially E. coli. Our data indicate that Enterobacteriaceae might play essential role in the pathogenesis and/or progress of AC. This was verified in an in vivo model using a pathogenic E. coli isolated from one of the patients in guinea pigs and observed marked gallbladder inflammation and morphologic changes. This study thus provides insight which could be useful for the prevention, diagnosis and treatment of AC and related diseases by controlling the growth of Enterobacteriaceae to alleviate the infection.

Detection of Helicobacter pylori infection in Egyptian patients with chronic calcular cholecystitis

Reports of Helicobacter pylori in biliary tract diseases in humans are very fragmentary, and therefore there is a need for further investigations. This study aims to detect H. pylori in the bile and gall bladder (GB) of patients with chronic calcular cholecystitis (CCC), and to determine the association of H. pylori infection with gallstone type. Thirty patients with CCC admitted for laparoscopic cholecystectomy were investigated, including upper gastro-endoscopy before cholecystectomy. Rapid urease test and histopathological examination were performed on gastric biopsies. The GB specimens were investigated for the presence of H. pylori by immunohistochemistry (IHC). H. pylori antigen in bile was detected by enzyme immunoassay. Chemical analysis of gallstones was performed to determine type. Immunohistochemistry testing showed 73.3% and 66.7% positivity among GB neck and body biopsies, respectively, demonstrating high sensitivity and specificity. A significant association was found between gastric and GB H. pylori positivity (P < 0.01). H. pylori antigen was detected in bile from three CCC cases. The greatest number of stones were of the calcium bilirubinate type. Gall bladder positivity for H. pylori was accompanied by chronic quiescent gastritis (40.9%). In conclusion, H. pylori infection may be an aetiological factor leading to cholecystitis. Gastric colonisation with H. pylori could be a source for GB infection, and the organism may act as a lithogenic component, especially in the context of pure pigmented gallstones.

Chronic and acute infection of the gall bladder by Salmonella Typhi: understanding the carrier state

Despite major treatment and prevention efforts, millions of new typhoid infections occur worldwide each year. For a subset of infected individuals, Salmonella enterica subsp. enterica serovar Typhi colonizes the gall bladder and remains there long after symptoms subside, serving as a reservoir for the further spread of the disease. In this Progress article, we explore recent advances in our understanding of the mechanisms by which Salmonella spp.--predominantly S. Typhi--colonize and persist in the human gall bladder.

Spontaneous gallbladder pathology in baboons

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Diagnosis and management of acute cholangitis

Bacterial infection that occurs in the setting of biliary obstruction can lead to acute cholangitis, a condition characterized by fever, abdominal pain and jaundice. Choledocholithiasis is the most common cause of acute cholangitis and is often associated with bacterial infection and colonization in addition to biliary obstruction. Iatrogenic introduction of bacteria into the biliary system most commonly occurs during endoscopic retrograde cholangiopancreatography in patients with biliary obstruction. The majority of patients with acute cholangitis respond to antibiotic therapy, but endoscopic biliary drainage is ultimately required to treat the underlying obstruction. Acute cholangitis is often diagnosed using the clinical Charcot triad criteria; however, recommendations from an international consensus meeting in Tokyo produced the most comprehensive recommendations for the diagnosis and management of acute cholangitis. These guidelines enable a more accurate diagnosis of acute cholangitis than do earlier methods, and they facilitate the classification of disease as mild, moderate or severe. Although these guidelines represent a notable advance toward defining a universally accepted consensus for the definition of acute cholangitis, they have several limitations. This Review discusses current recommendations for the diagnosis of acute cholangitis and addresses the advantages and disadvantages of different modalities for the treatment of this disease.

Gallstones and the risk of biliary tract cancer: a population-based study in China

We conducted a population-based study of 627 patients with biliary tract cancers (368 of gallbladder, 191 bile duct, and 68 ampulla of Vater), 1037 with biliary stones, and 959 healthy controls randomly selected from the Shanghai population, all personally interviewed. Gallstone status was based on information from self-reports, imaging procedures, surgical notes, and medical records. Among controls, a transabdominal ultrasound was performed to detect asymptomatic gallstones. Gallstones removed from cancer cases and gallstone patients were classified by size, weight, colour, pattern, and content of cholesterol, bilirubin, and bile acids. Of the cancer patients, 69% had gallstones compared with 23% of the population controls. Compared with subjects without gallstones, odds ratios associated with gallstones were 23.8 (95% confidence interval (CI), 17.0–33.4), 8.0 (95% CI 5.6–11.4), and 4.2 (95% CI 2.5–7.0) for cancers of the gallbladder, extrahepatic bile ducts, and ampulla of Vater, respectively, persisting when restricted to those with gallstones at least 10 years prior to cancer. Biliary cancer risks were higher among subjects with both gallstones and self-reported cholecystitis, particularly for gallbladder cancer (OR=34.3, 95% CI 19.9–59.2). Subjects with bile duct cancer were more likely to have pigment stones, and with gallbladder cancer to have cholesterol stones (P<0.001). Gallstone weight in gallbladder cancer was significantly higher than in gallstone patients (4.9 vs 2.8 grams; P=0.001). We estimate that in Shanghai 80% (95% CI 75–84%), 59% (56–61%), and 41% (29–59%) of gallbladder, bile duct, and ampulla of Vater cancers, respectively, could be attributed to gallstones.

Influence of duodenal-biliary reflux on formation of bile duct pigment gallstone

AIM: To investigate the possible action and mechanism of duodenal-biliary reflux in the pathogenesis of bile duct pigment gallstone.

METHODS: Forty-eight patients were divided into three groups: polyp of gallbladder (PG, n = 10), cholecystolithiasis (CH, n = 27) and calculus of bile duct (CBD, n = 11). Bile samples were collected during operation for bacterial culture and endotoxin examination. Forty-one patients received T tube drainage after cholecystectomy and choledochotomy were divided into reflux (n = 16) and non-reflux group (n = 25) according to radionuclide examination. The activity of biliary amylase, lipase and β-glucuronidase were detected in 26 of the 41 patients.

RESULTS: The positive rate of bacterial culture was 0% in PG group, 0% in CH group and 81.8% in CBD group, and the level of endotoxin in bile was (0.003 ± 0.004) × 10^-6, (0.01 ± 0.02) × 10^-6, and (10.12 ± 4.49) × 10^-6 EU/L the above corresponding group, respectively. Compared with those in the former two groups, the positive rate and endotoxin level were higher in the latter CBD group (P < 0.01). Sixteen patients showed duodenal-biliary reflux (39.02%) among 41 patients. The activities of biliary amylase, lipase and exogenous β-glucuronidase in reflux group was significantly higher than those in non-reflux group (amylase: 79 891 ± 91 152 nkat/L vs 582 ± 928 nkat/L, P < 0.01; lipase: 86 110 ± 58 255 nkat/L vs 6 124 ± 7 500 nkat/L, P < 0.01; β-glucuronidase: 27 789 ± 13 849 nkat/L vs 15 369 ± 7 533 nkat/L, P < 0.01).

CONCLUSION: Duodenal-biliary reflux can promote the formation of pigment gallstone through bacteria, endotoxin, amylase, lipase and exogenous β-glucuronidase.

Influence of intestinal barrier function on pigment gallstone formation in guinea pig model

AIM: To investigate the possible action and mechanism of the intestinal barrier function in the pathogenesis of pigment gallstone.

METHODS: Eighty guinea pigs were randomly divided into three groups: normal group (CON), pigment gallstone group (PS) and intestinal mucosa protection group (GLN). Normal forage, pigment gallstone-forming forage and pigment gallstone-forming forage with supplemental intestinal mucosa protector (glutamine) were given to the animals of corresponding groups, respectively. The gallstone-forming rate, morphological changes of intestinal mucosa, intestinal permeability, serum endotoxin and biliary β-glucuronidase were detected after 8 wk.

RESULTS: The gallstone-forming rate was 73.9% in PS. In comparison with those in CON, the intestinal mucosa damage, serum endotoxin level [(1367±525)×10^-6 EU/L vs (77±43) ×10^-6 EU/L, P < 0.01] and activity of biliary β-glucuronidase (endogenous: from 209.8±47.5 vs 122.1±39.5 Fishman Unit, P < 0.01; exogenous: from 2206.6±983.9 vs 573.5±476.9 Fishman Unit, P < 0.01) were significantly increased in PS. In GLN, the gallstone-forming rate was decreased to 44.4%, which was markedly higher than that in PS (P < 0.05). The morphological changes of intestinal mucosa, intestinal permeability and serum endotoxin [(156±97)×10^-6 EU/L vs (1367±525)×10^-6 EU/L, P < 0.05] were notably decreased in GLN as compared with those in PS, and there was no significant difference in β-glucuronidase activity.

CONCLUSION: Intestinal barrier function is correlated with pigment gallstone formation. Intestinal barrier function disorder may promote pigment gallstone formation through bacteria translocation, endotoxemia and change of biliary β-glucuronidase activity.

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Origin of oxysterols in hepatic bile of patients with biliary infection

OBJECTIVES

Oxysterols are ubiquitous in the body and are potential cytotoxic agents in addition to being metabolic regulators. Although bile contains high concentrations of cholesterol, oxysterol concentrations in bile and the effect of infection on oxysterol levels have not been measured, nor has their origin been studied. The purpose of this study was to determine if infection of the biliary tract was associated with increased concentrations of oxysterols in the bile and, if so, which oxysterols showed a significant change.

METHODS

Hepatic bile was obtained from eight patients with biliary tract disease by means of a naso-biliary catheter. Oxysterols were extracted and purified by solid-phase extraction, derivatized and measured by gas chromatography-mass spectrometry.

RESULTS

The following were quantified in hepatic bile: 7-alpha-hydroxycholesterol, 7-beta-hydroxycholesterol, cholestan-3-beta,5-alpha,6-beta-triol, 25-hydroxycholesterol, 26-hydroxycholesterol, 7-ketocholesterol, and 7-alpha-hydroxy-4-cholesten-3-one. Total oxysterols in hepatic bile ranged from 0.133 mumol/L to 7.748 mumol/L (1.47 +/- 2.55 mumol/L). Levels of 7-alpha-hydroxycholesterol and 7-beta-hydroxycholesterol were increased in infected bile (14.2 +/- 15.1 x 10(-3)% of cholesterol vs 1.9 +/- 0.5 x 10(-3)% of cholesterol, p < 0.05, and 22.0 +/- 25.0 x 10(-3)% of cholesterol vs 1.6 +/- 1.2 x 10(-3)% of cholesterol, p < 0.05, respectively). Serum C-reactive protein levels correlated positively with biliary levels of 7-alpha-hydroxycholesterol (R = 0.948), 7-beta-hydroxycholesterol (R = 0.976), cholestan-3-beta,5-alpha,6-beta-triol (R = 0.823), 7-alpha-hydroxy-4-cholesten-3-one (R = 0.846,) and 7-ketocholesterol (R = 0.973). Different oxysterols were found in gallstones, chiefly 3-keto-cholest-4-ene (624 +/- 316 parts per million [ppm] of dry weight), 3-keto-cholesta-4,6-diene (240 +/- 329 ppm) and 7-keto-cholesterol (77 +/- 81 ppm). Incubation of human leukocytes with model bile in the presence of bacterial lipopolysaccharide resulted in changes in sterol composition, including increases in oxysterols. We have identified and quantified oxysterols from uninfected and infected human hepatic bile and from gallstones and gallbladder bile. Biliary infection may be involved in the biogenesis of oxysterols in bile through the production of reactive oxygen species from activated leukocytes.

Review article: Helicobacter species and hepatobiliary diseases

Helicobacter species, which may colonize the biliary tract, have been implicated as a possible cause of hepatobiliary diseases ranging from chronic cholecystitis and primary sclerosing cholangitis to gall-bladder carcinoma and primary hepatic carcinomas. Research in this area has been limited by the lack of a gold standard in the diagnosis of these organisms in bile. Most published data to date have been based on molecular techniques that detect the DNA of Helicobacter species in bile, rather than evidence of viable organisms in bile. Helicobacter species have not been shown to induce histological injury to the biliary epithelium or liver parenchyma. The strongest association of the presence of these organisms in bile is with cholestatic conditions. This article reviews the literature on this newly developing field as it has evolved historically, taking pertinent methodological issues into account.