Selection and timing of liver transplantation in primary biliary cirrhosis and primary sclerosing cholangitis.

In summary, we answer the three questions we have previously posed: (a) Can liver transplantation prolong survival? Evolving data from several centers indicate that liver transplantation indeed prolongs survival in patients with PBC and PSC as compared with estimated survival using disease-specific risk scores based on the natural history of PBC and PSC. (b) Can we optimize timing of liver transplantation? Although many factors enter into the timing of liver transplantation, including when the patient is actually referred for liver transplantation and the individual desires of the patient to pursue liver transplantation, evidence is growing that having patients with chronic liver diseases like PBC and PSC undergo transplantation a little earlier in the course of the disease rather than waiting until the patients have experienced life-threatening complications or are on life-support measures can indeed improve early postliver transplant survival. In patients with PBC and PSC, the survival risk score, which reflects disease severity, can serve as an objective measurement to assess and evaluate the effect of liver disease severity on transplant outcome. Indeed, a number of studies have strongly suggested that optimal timing of liver transplantation may indeed be important to improve outcome, decrease morbidity and decrease cost. (c) Does the present allocation system in the United States allow for optimal use of our scarce donor organ resource?(ABSTRACT TRUNCATED AT 250 WORDS)     

Cryptosporidium parvum activates nuclear factor kappaB in biliary epithelia preventing epithelial cell apoptosis

BACKGROUND & AIMS: Our previous studies have shown that Cryptosporidium parvum induces biliary epithelial cell apoptosis in vivo and causes apoptosis in bystander uninfected biliary epithelia in vitro. We analyzed C. parvum-induced nuclear factor kappa B (NF-kappaB) activation in human biliary epithelial cells and assessed its relevance to epithelial cell apoptosis. METHODS: In vitro models of cryptosporidial infection using a human biliary epithelial cell line were used to assay C. parvum- induced NF-kappaB activation and associated apoptosis. RESULTS: Degradation of I(kappa)B and nuclear translocation of the NF-kappaB family of proteins (p65 and p50) were observed in the biliary epithelial cell cultures directly exposed to the parasite. Activation of NF-kappaB was found only in directly infected cells (but not in bystander uninfected cells). A time-dependent secretion of a known NF-kappaB gene product, interleukin 8, from infected cell cultures was detected. C. parvum-induced biliary epithelial cell apoptosis was limited to bystander uninfected cells. In contrast, inhibition of NF-kappaB activation resulted in apoptosis in directly infected cells and significantly enhanced C. parvum-induced apoptosis in bystander uninfected cells. CONCLUSIONS: These observations support the concept that, while C. parvum triggers host cell apoptosis in bystander uninfected biliary epithelial cells, which may limit spread of the infection, it directly activates the NF-kappaB/I(kappa)B system in infected biliary epithelia thus protecting infected cells from death and facilitating parasite survival and propagation.     

Magnetic resonance cholangiography in patients with biliary disease: its role in primary sclerosing cholangitis

BACKGROUND/AIM: Magnetic resonance cholangiography (MRC) is a non-invasive diagnostic procedure whose role in the management of patients with primary sclerosing cholangitis (PSC) is unclear. The aim of this study was to determine the usefulness of MRC in the evaluation of the biliary tree in patients with suspected biliary disease, and in particular, PSC. METHODS: MRC and invasive cholangiography (ERCP or PTC) were both performed in 73 patients, (33 male, 40 female, mean age 56 years) with clinical and/or biochemical evidence of cholestasis. Images were interpreted by two radiologists unaware of the results of other studies. RESULTS: Forty-two patients (58%) had benign biliary disease, including 23 patients (32%) with PSC; 9 patients (12%) had malignant biliary disease; and 22 patients (30%) had a normal biliary tree. Diagnostic quality images were obtained in 73/73 (100%) of MRC, and in 70/73 (96%) of invasive cholangiography (68 ERCP's, 2 PTC's) procedures. Using ERCP/PTC findings as the reference standard, MRC had an accuracy greater than 90% in the diagnosis of normal bile ducts, biliary dilatation, biliary obstruction, bile duct stones, and PSC. Using the final diagnosis, MRC had an overall diagnostic accuracy of 90% in the detection of biliary disease compared to 97% for invasive cholangiography. Additional diagnostic/therapeutic interventions were performed during ERCP in 73% of patients with PSC and in 43% of patients without PSC (p=0.02). CONCLUSIONS: MRC has excellent diagnostic accuracy in the presence of biliary disease. Because of its noninvasive nature, MRC may have advantages over invasive cholangiography when diagnosis is the major goal of the procedure.     

Macrophages contribute to the pathogenesis of sclerosing cholangitis in mice

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Effect of primary bile acid ingestion on bile acid metabolism and biliary lipid secretion in gallstone patients.

Bile acid kinetics were measured by isotope dilution, and hourly outputs of bile acid, cholesterol, and phospholipid were quantified by duodenal perfusion over 24 hr including three liquid meals and an overnight fast in 6 gallstone patients during a pretreatment period and two randomized treatment periods with chenodeoxycholic (chenic) acid or cholic acid. During chenic acid ingestion, bile contained predominantly chenyl conjugates. During cholic acid ingestion, bile was composed of about equal amounts of cholyl and deoxycholyl conjugates; chenyl conjugates decreased markedly due in part to a 50% decrease in chenic acid synthesis. Total bile acid pool size doubled in half the patients receiving either bile acid and was not different during treatment with chenic or cholic acid. Compared to cholic acid, chenic acid caused decreased cholesterol output with no difference in bile acid or phospholipid output. Therefore, bile unsaturated with cholesterol entered the duodenum for more hours per day during chenic acid ingestion than during the cholic or pretreatment periods. There was no relationship among bile acid pool size, bile acid output, and hours per day of supersaturated bile; there was an inverse relationship between total pool size and recycling frequency such that bile acid output remained stable over a wide range of pool sizes. Fasting-state gallbladder bile was supersaturated during the cholic and pretreatment periods, but became unsaturated during chenic acid ingestion. However, hours per day of supersaturated bile could not be reliably predicted from the degree of saturation of fasting-state gallbladder bile (r = 0.62). The efficacy of chenic acid and the lack of efficacy of cholic acid for gallstone dissolution appear related to their different specific effects on biliary cholesterol secretion and not to any effect on bile acid and phospholipid secretion or bile acid pool size.     

Biological characteristics of primary cultures of human gallbladder epithelial cells.

Epithelial cells of the gallbladder have potential to represent an important model for studies of ductal epithelial in normal and pathological states. We therefore initiated studies to establish human gallbladder epithelial cells (GBEC) in culture. GBEC were isolated by trypsinization of small tissue fragments from human gallbladders obtained at cholecystectomy; cells were plated on tissue culture dishes and grown in defined MCDB 153 medium containing added growth factors. In this medium, GBEC showed a plating efficiency of approximately 1%; those GBEC that attached formed colonies and proliferated, as demonstrated by autoradiographic analysis of [3H]thymidine incorporation into DNA. Cultured GBEC expressed two markers found on GBEC in situ, i.e., gamma-glutamyl transpeptidase and cytokeratin 19. By using various attachment substrates, with and without added serum, increased plating efficiency and better growth were achieved. When type IV collagen was used as substrate and 10% fetal bovine serum was added to MCDB 153, passage of GBEC was possible, and cells proliferated through five to six population doublings. GBEC in culture under all conditions eventually enlarged, showed vacuolization, and demonstrated irreversible growth arrest. Nonetheless, the culture conditions described here allow for preparation of large quantities of highly enriched human GBEC.     

Gallbladder ablation through radiologic intervention: an experimental alternative to cholecystectomy

Twenty pigs underwent (a) cystic duct occlusion by means of fluoroscopically guided transcatheter endoluminal bipolar radio-frequency (RF) electrocoagulation and (b) gallbladder sclerotherapy with one of two different regimens of ethanol and sodium tetradecyl-sulfate (STS). Serum ethanol levels and hepatic enzyme tests showed no acute toxicity. Postmortem histologic studies showed that the bile ducts beyond the occlusion site remained entirely unaffected in all animals. In three of four animals followed up for 2 weeks, the sclerosants induced necrosis of the gallbladder mucosa, but the adjacent liver, serosa, and blood vessels remained intact. In 13 of 16 animals followed up for 8 weeks, the gallbladder lumen was obliterated by fibrous scar tissue. In the animals treated with 95% ethanol and 3% STS, the gallbladder mucosa was necrotic in all areas after 2 weeks (two of two animals) and eradicated completely after 8 weeks (six of eight animals); the other regimen (70% ethanol plus 1% STS) was somewhat less effective. In this study, the combination of RF-mediated cystic duct occlusion and gallbladder sclerotherapy with ethanol and STS permitted gallbladder ablation in swine without toxic side effects.