Clinical epidemiology of primary biliary cirrhosis: incidence, prevalence, and impact of therapy

Gender and Racial Differences in Hospitalizations for Primary Biliary Cholangitis in the USA

BACKGROUND/AIM

The prevalence, characteristics, burden and trends of primary biliary cholangitis (PBC) hospitalizations in the USA remain unclear.

METHOD

We identified primary PBC hospitalizations from the National Inpatient Sample (NIS) 2007 through 2014 using ICD-9-CM codes. We calculated the rates and trends of hospitalization for PBC per 100,000 US population among each gender (males and females) and racial categories (Whites, Blacks, Hispanics and other racial minorities), and measured the predictors of hospitalization, and of mortality, charges and length of stay (LOS) among PBC hospitalizations.

RESULT

There were 8460 (weighted: 41,191) PBC hospitalizations between 2007 and 2014. The mean national PBC hospitalization rate was 2.2 cases per 100,000 population (2.2/100,000), increasing from 1.7/100,000 (2007) to 2.5/100,000 (2014). From 2007 to 2014, the in-hospital mortality and LOS were unchanged while the charges increased from $65,993 to $73,093 ($225 million to $447 million overall expenses). Compared to Whites, the PBC hospitalization rate was 12% higher among Hispanics (RR: 1.12 [1.09-1.16]), 53% lower in Blacks (RR: 0.47 [0.45-0.49]) and 5% lower among other racial minorities (0.95 [0.91-0.99]). The rate was higher among females (RR:4.02 [3.93-4.12]) compared to males. On multivariate analysis, Blacks and other racial minorities, respectively, had higher odds of mortality (AOR: 1.47 [1.03-2.10] and 1.33 [0.96-1.84]), while other racial minorities had longer LOS (7.0 vs. 5.6 days) and higher hospital charges ($48,984 vs. $41,495) when compared to Whites.

CONCLUSION

The hospitalization rate and burden of PBC in the USA have increased disproportionately among females and Hispanics with higher mortality in Blacks.

Factors Associated With Potential Progressive Course of Primary Biliary Cholangitis: Data From Real-world US Database

BACKGROUND AND AIMS

Although relatively, primary biliary cholangitis (PBC) is an important cause of nonalcoholic chronic liver disease which may lead to liver transplantation. PBC patients with alkaline phosphatase (ALP) ≥1.5× the upper limit of normal (ULN) tend to have a more aggressive course. The study was designed to identify factors associated with ALP≥1.5×ULN or cirrhosis in PBC and to evaluate concomitant health care resource utilization.

METHODS

We used a large real-world database that contained comprehensive and continuous electronic medical recored/claims data from over 500 health care practices or systems from the United States.

RESULTS

Of 195 million patients included in the database, 36,317 were adults with PBC. After applying exclusion criteria, 15,875 patients comprised the final PBC cohort (63.0±13.5 y, 78% female, 71% privately insured, 5% covered by Medicaid, 57% with other autoimmune diseases, 46% with cirrhosis); 6083 (38%) had ALP≥1.5×ULN. Patients with ALP≥1.5×ULN were more frequently female, less covered by Medicaid, had more pruritus, cirrhosis, and other autoimmune diseases (P<0.05). In multivariate analysis, older age, female gender, the presence of other autoimmune diseases, and having compensated or decompensated cirrhosis were independently associated with having ALP≥1.5×ULN in PBC (P<0.05). In contrast, being male was associated with higher risk of cirrhosis in PBC [odds ratio 2.3 (95% confidence interval, 2.1-2.5)]. Patients with ALP≥1.5×ULN and/or with cirrhosis also incurred substantially more health care resource utilization (P<0.05).

CONCLUSIONS

Many clinical, sociodemographic, and economic factors are associated with a potentially more aggressive profile of PBC with elevated ALP. These data may inform clinicians to implement management strategies to optimize care of these patients.

Primary Biliary Cholangitis in Medicare Population: The Impact on Mortality and Resource Use

Primary biliary cholangitis (PBC) is a disease of small bile ducts, which can lead to morbidity and mortality. Our aim was to assess recent trends in mortality and healthcare use of PBC patients in the Medicare program. Data from Medicare beneficiaries between 2005 and 2015 (5% random samples) were used. The diagnosis of PBC was established with International Classification of Diseases-9 code 571.6 used for both primary and secondary diagnoses. Mortality was assessed by Medicare-linked death registry. Healthcare use included episodes of care, length of stay, and total charges/payments. Independent predictors of outcomes were evaluated in multiple generalized linear or logistic regression models. The study cohort included a total of 6,375 inpatient/outpatient Medicare beneficiaries (mean age 69.8 years, 17% male, 88% white, and 18% with disability). Over the study period, 1-year mortality remained stable (9.1% to 14.3%, P = 0.11). Independent predictors of 1-year mortality were older age, male gender, black race, the presence of ascites, encephalopathy, hepatocellular carcinoma, and higher Charlson score. Outpatient total yearly charges and payments per beneficiary with PBC increased from $3,065 and $777 (2005) to $5,773 and $967 (2014), respectively. Similarly, inpatient total yearly charges and payments per beneficiary with PBC increased from $59,765 and $19,406 (2007), to $98,941 and $27,948 (2013), respectively (P < 0.05). The presence of ascites, portal hypertension, and higher Charlson score were independent predictors of higher payments for both inpatient and outpatient resource use, and the presence of hepatic encephalopathy was an additional predictor of higher inpatient resource use (all P < 0.02). Conclusion: The prevalence of PBC among the Medicare beneficiaries has increased. Despite stable mortality rates, resource use for Medicare patients with PBC continues to rise.

Targeted Metabolomics Reveals a Protective Role for Basal PPARα in Cholestasis Induced by α-Naphthylisothiocyanate

α-Naphthylisothiocyanate (ANIT) is an experimental agent used to induce intrahepatic cholestasis. The Ppara-null mouse line is widely employed to explore the physiological and pathological roles of PPARα. However, little is known about how PPARα influences the hepatotoxicity of ANIT. In the present study, wild-type and Ppara-null mice were orally treated with ANIT to induce cholestasis. The serum metabolome of wild-type mice segregated from that of the Ppara-null mice, driven by changes of bile acid (BA) metabolites. Alkaline phosphatase and total BAs were elevated preferentially in Ppara-null mice, which correlated with changes in Cyp7a1, Cyp8b1, Mrp3, Cyp3a11, Cyp2b10, Ugt1a2, and Ugt1a5 genes and showed cross-talk between basal PPARα and potentially adaptive pathways. Il6, Tnfa, and target genes in the STAT3 pathway ( Socs3, Fga, Fgb, and Fgg) were up-regulated in Ppara-null mice but not in wild-type mice. The JNK pathway was activated in both mouse lines, while NF-κB and STAT3 were activated only in Ppara-null mice. These data suggest protection against cholestasis by basal PPARα involves regulation of BA metabolism and inhibition of NF-κB/STAT3 signaling. Considering studies on the protective effects of both basal and activated PPARα, caution should be exercised when one attempts to draw conclusions in which the PPARα is modified by genetic manipulation, fasting, or activation in pharmacological and toxicological studies.

New developments in the treatment of primary biliary cholangitis - role of obeticholic acid

Primary biliary cholangitis (PBC) is a chronic autoimmune cholestatic liver disease that predominantly affects women in early to middle age. It is typically associated with autoantibodies to mitochondrial antigens and results in immune-mediated destruction of small and medium-sized intrahepatic bile ducts leading to cholestasis, hepatic fibrosis and may progress to cirrhosis or hepatic failure and, in some cases, hepatocellular carcinoma. The clinical presentation and the natural history of PBC have improved over the years due to recognition of earlier widespread use of ursodeoxycholic acid (UDCA); about one-third of patients show suboptimal biochemical response to UDCA with poor prognosis. Until recently, UDCA was the only US Food and Drug Administration approved agent for this disease for more than two decades; obeticholic acid was approved in 2016 for treatment of patients with PBC with a suboptimal response or intolerance to UDCA. Currently, liver transplantation is the most effective treatment modality for PBC patients with end-stage liver disease. This review will focus on the recent advances in therapy of primary biliary cholangitis, with emphasis on obeticholic acid.

Inhibition of JNK signalling mediates PPARα-dependent protection against intrahepatic cholestasis by fenofibrate

BACKGROUND AND PURPOSE

Fenofibrate, a PPARα agonist, is the most widely prescribed drug for treating hyperlipidaemia. Although fibrate drugs are reported to be beneficial for cholestasis, their underlying mechanism has not been determined.

EXPERIMENTAL APPROACH

Wild-type mice and Pparα-null mice were pretreated orally with fenofibrate for 3 days, following which α-naphthylisothiocyanate (ANIT) was administered to induce cholestasis. The PPARα agonist WY14643 and JNK inhibitor SP600125 were used to determine the role of PPARα and the JNK pathway, respectively, in cholestatic liver injury. The same fenofibrate regimen was applied to investigate its beneficial effects on sclerosing cholangitis in a DDC-induced cholestatic model.

KEY RESULTS

Fenofibrate, 25 mg·kg^-1 twice a day, totally attenuated ANIT-induced cholestasis and liver injury as indicated by biochemical and histological analyses. This protection occurred in wild-type, but not in Pparα-null, mice. Alterations in bile acid synthesis and transport were found to be an adaptive response rather than a direct effect of fenofibrate. WY14643 attenuated ANIT-induced cholestasis and liver injury coincident with inhibition of JNK signalling. Although SP600125 did not affect cholestasis, it inhibited liver injury in the ANIT model when the dose of fenofibrate used was ineffective. Fenofibrate was also revealed to have a beneficial effect in the sclerosing cholangitis model.

CONCLUSIONS AND IMPLICATIONS

These data suggest that the protective effects of fenofibrate against cholestasis-induced hepatic injury are dependent on PPARα and fenofibrate dose, and are mediated through inhibition of JNK signalling. This mechanism of fenofibrate protection against intrahepatic cholestasis may offer additional therapeutic opportunities for cholestatic liver diseases.

Positive antimitochondrial antibody but normal serum alkaline phosphatase levels: Could it be primary biliary cholangitis?

AIM

Primary biliary cholangitis (PBC) is a chronic cholestatic liver disease, typically diagnosed by elevated cholestatic liver enzymes and a positive antimitochondrial antibody (AMA) test. The clinical significance of AMA positivity in patients with normal cholestatic liver enzymes is uncertain.

METHODS

Charts of patients with normal cholestatic liver enzymes and AMA positivity who underwent liver biopsy between 2012 and 2015 were retrospectively analyzed.

RESULTS

Six AMA-positive patients with normal cholestatic liver enzymes who underwent a liver biopsy were identified. Four (67%) showed florid bile duct lesion compatible with early-stage PBC, whereas the other two showed mild and non-specific histological findings. The patients with histological findings compatible with PBC had higher enzyme-linked immunosorbent assay-determined AMA titers and significantly elevated immunoglobulin M (IgM) level. Patients with non-specific histological findings (33%) had low-titer AMA and a borderline elevated IgM level.

CONCLUSIONS

Antimitochondrial antibody-positive patients with normal cholestatic liver enzymes should be meticulously evaluated for PBC including a liver biopsy, mainly in patients with high-titer seropositivity for AMA and a significantly elevated IgM level. More studies are required to clarify the role of liver biopsy in these patients and further follow-up may elucidate the relationship of these patients to those with more classical forms of PBC.

Lessons learned from twins in autoimmune and chronic inflammatory diseases

Autoimmunity and chronic inflammation recognize numerous shared factors and, as a result, the resulting diseases frequently coexist in the same patients or respond to the same treatments. Among the convenient truths of autoimmune and chronic inflammatory diseases, there is now agreement that these are complex conditions in which the individual genetic predisposition provides a rate of heritability. The concordance rates in monozygotic and dizygotic twins allows to estimate the weight of the environment in determining disease susceptibility, despite recent data supporting that only a minority of immune markers depend on hereditary factors. Concordance rates in monozygotic and dizygotic twins should be evaluated over an observation period to minimize the risk of false negatives and this is well represented by type I diabetes mellitus. Further, concordance rates in monozygotic twins should be compared to those in dizygotic twins, which share 50% of their genes, as in regular siblings, but also young-age environmental factors. Twin studies have been extensively performed in several autoimmune conditions and cumulatively suggest that some diseases, i.e. celiac disease and psoriasis, are highly genetically determined, while rheumatoid arthritis or systemic sclerosis have a limited role for genetics. These observations are necessary to interpret data gathered by genome-wide association studies of polymorphisms and DNA methylation in MZ twins. New high-throughput technological platforms are awaited to provide new insights into the mechanisms of disease discordance in twins beyond strong associations such as those with HLA alleles.

Pharmacological interventions for primary biliary cholangitis: an attempted network meta-analysis

BACKGROUND

Primary biliary cholangitis (previously primary biliary cirrhosis) is a chronic liver disease caused by the destruction of small intra-hepatic bile ducts resulting in stasis of bile (cholestasis), liver fibrosis, and liver cirrhosis. The optimal pharmacological treatment of primary biliary cholangitis remains uncertain.

OBJECTIVES

To assess the comparative benefits and harms of different pharmacological interventions in the treatment of primary biliary cholangitis through a network meta-analysis and to generate rankings of the available pharmacological interventions according to their safety and efficacy. However, it was not possible to assess whether the potential effect modifiers were similar across different comparisons. Therefore, we did not perform the network meta-analysis, and instead, assessed the comparative benefits and harms of different interventions using standard Cochrane methodology.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 2), MEDLINE, Embase, Science Citation Index Expanded, World Health Organization International Clinical Trials Registry Platform, and randomised controlled trials registers to February 2017 to identify randomised clinical trials on pharmacological interventions for primary biliary cholangitis.

SELECTION CRITERIA

We included only randomised clinical trials (irrespective of language, blinding, or publication status) in participants with primary biliary cholangitis. We excluded trials which included participants who had previously undergone liver transplantation. We considered any of the various pharmacological interventions compared with each other or with placebo or no intervention.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. We calculated the odds ratio (OR) and rate ratio with 95% confidence intervals (CI) using both fixed-effect and random-effects models based on available-participant analysis with Review Manager 5. We assessed risk of bias according to Cochrane, controlled risk of random errors with Trial Sequential Analysis, and assessed the quality of the evidence using GRADE.

MAIN RESULTS

We identified 74 trials including 5902 participants that met the inclusion criteria of this review. A total of 46 trials (4274 participants) provided information for one or more outcomes. All the trials were at high risk of bias in one or more domains. Overall, all the evidence was low or very low quality. The proportion of participants with symptoms varied from 19.9% to 100% in the trials that reported this information. The proportion of participants who were antimitochondrial antibody (AMA) positive ranged from 80.8% to 100% in the trials that reported this information. It appeared that most trials included participants who had not received previous treatments or included participants regardless of the previous treatments received. The follow-up in the trials ranged from 1 to 96 months.The proportion of people with mortality (maximal follow-up) was higher in the methotrexate group versus the no intervention group (OR 8.83, 95% CI 1.01 to 76.96; 60 participants; 1 trial; low quality evidence). The proportion of people with mortality (maximal follow-up) was lower in the azathioprine group versus the no intervention group (OR 0.56, 95% CI 0.32 to 0.98; 224 participants; 2 trials; I² = 0%; low quality evidence). However, it has to be noted that a large proportion of participants (25%) was excluded from the trial that contributed most participants to this analysis and the results were not reliable. There was no evidence of a difference in any of the remaining comparisons. The proportion of people with serious adverse events was higher in the D-penicillamine versus no intervention group (OR 28.77, 95% CI 1.57 to 526.67; 52 participants; 1 trial; low quality evidence). The proportion of people with serious adverse events was higher in the obeticholic acid plus ursodeoxycholic acid (UDCA) group versus the UDCA group (OR 3.58, 95% CI 1.02 to 12.51; 216 participants; 1 trial; low quality evidence). There was no evidence of a difference in any of the remaining comparisons for serious adverse events (proportion) or serious adverse events (number of events). None of the trials reported health-related quality of life at any time point.

FUNDING

nine trials had no special funding or were funded by hospital or charities; 31 trials were funded by pharmaceutical companies; and 34 trials provided no information on source of funding.

AUTHORS' CONCLUSIONS

Based on very low quality evidence, there is currently no evidence that any intervention is beneficial for primary biliary cholangitis. However, the follow-up periods in the trials were short and there is significant uncertainty in this issue. Further well-designed randomised clinical trials are necessary. Future randomised clinical trials ought to be adequately powered; performed in people who are generally seen in the clinic rather than in highly selected participants; employ blinding; avoid post-randomisation dropouts or planned cross-overs; should have sufficient follow-up period (e.g. five or 10 years or more); and use clinically important outcomes such as mortality, health-related quality of life, cirrhosis, decompensated cirrhosis, and liver transplantation. Alternatively, very large groups of participants should be randomised to facilitate shorter trial duration.

Novel Therapies on Primary Biliary Cirrhosis

All patients with primary biliary cirrhosis (PBC) and abnormal liver biochemistry should be considered for specific therapy. Ursodeoxycholic acid (UDCA) is the only FDA-approved drug for treating PBC. Approximately 40% of patients with PBC respond incompletely to treatment with UDCA, thus having increased risk of death or need for liver transplantation. No second-line therapies for patients with inadequate response to UDCA therapy have been approved. This review provides a current perspective on potential new approaches to treatment in PBC, and highlights some of the challenges we face in evaluating and effectively implementing those treatments.

Pathophysiology and Diseases of the Proximal Pathways of the Biliary System

CONTEXT

Diseases of the proximal pathways of the biliary system can be divided into those that affect the interlobular bile ducts and those that affect the bile canaliculi. The former include primary biliary cirrhosis, small-duct variant of primary sclerosing cholangitis, graft-versus-host disease, and drug-induced liver injury, whereas the latter include progressive familial intrahepatic cholestasis, benign recurrent intrahepatic cholestasis, intrahepatic cholestasis of pregnancy, and drug-induced liver injury.

OBJECTIVE

To summarize the current state of knowledge of diseases of the proximal pathways of the biliary system, with special emphasis on clinical presentation, pathological features, and differential diagnosis.

DATA SOURCES

Clinicopathological information was extracted from pertinent published literature.

CONCLUSIONS

Care of the patient with cholestasis hinges on identifying the etiology. Diagnostic steps in cholestatic conditions comprise a thorough patient history, abdominal imaging, distinct serological studies, and liver biopsy. Primary biliary cirrhosis is characterized by distinctive serological and histological findings. The small-duct variant of primary sclerosing cholangitis is very rare and difficult to diagnose; imaging of the bile ducts is not helpful. Graft-versus-host disease is characterized by damage and loss of intrahepatic bile ducts. Drugs can cause injury variably at the level of bile canaliculus or the interlobular bile duct. Loss of bile ducts may be seen with primary biliary cirrhosis, primary sclerosing cholangitis, graft-versus-host disease, and drug-induced liver injury. Progressive familial intrahepatic cholestasis and progressive familial intrahepatic cholestasis represent 2 extreme ends of the spectrum of abnormalities in transporters responsible for bile formation. Intrahepatic cholestasis of pregnancy has a variable incidence in different parts of the world and may be due to abnormalities in transporter molecules.

Primary biliary cirrhosis: Clinical and laboratory criteria for its diagnosis

Primary biliary cirrhosis (PBC) is a chronic progressive cholestatic granulomatous, and destructive inflammatory lesion of small intralobular and septal bile ducts, which is likely to be caused by an autoimmune mechanism with a the presence of serum antimitochondrial antibodies and a potential tendency to progress to cirrhosis. Despite the fact that the etiology of this disease has been unknown so far, there has been a considerable body of scientific evidence that can reveal the clinical and laboratory signs of PBC and the individual components of its pathogenesis and elaborate diagnostic criteria for the disease and its symptomatic therapy. Deficiencies in autoimmune tolerance are critical factors for the initiation and perpetuation of the disease. The purpose of this review is to summarize the data available in the literature and the author’s findings on clinical and laboratory criteria for the diagnosis of PBC. This review describes the major clinical manifestations of the disease and the mechanisms of its development. It presents the immunological, biochemical, and morphological signs of PBC and their significance for its diagnosis. A great deal of novel scientific evidence for the problem of PBC has been accumulated. However, the inadequate efficiency of therapy for the disease lends impetus to the quest for its etiological factors and to further investigations of its pathogenetic mechanisms and, on this basis, to searches for new methods for its early diagnosis.

Progress in treatment of primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is a chronic autoimmune cholestatic liver disease characterized by cholestasis, and it often eventually develops into cirrhosis, portal hypertension and liver failure. Asymptomatic patients typically are diagnosed by the elevation of alkaline phosphatase (ALP) and the presence of anti-mitochondrial antibody (AMA) titers of 1:40 or greater. Ursodeoxycholic acid (UDCA) is the only Food and Drug Administration approved treatment for PBC, but it is not universally effective. In patients with UDCA-refractory PBC, additional therapies should be considered, including budesonide, fibrates, obeticholic acid, immunosuppressants and liver transplantation.

Fibrate treatment for primary biliary cirrhosis

PURPOSE OF REVIEW

Primary biliary cirrhosis (PBC) can lead to end-stage liver disease and death. Ursodeoxycholic acid (UDCA) treatment can normalize serum liver enzymes in PBC, and such UDCA-responsive patients have a similar life expectancy as age and sex-matched controls. Nearly up to 50% of the patients with PBC, depending on sex and age at diagnosis, show an incomplete biochemical response to UDCA and require additional/alternative treatment. The purpose of this review is to critically evaluate the molecular mechanisms and clinical benefit of fibrate treatment in these patients.

RECENT FINDINGS

Fibrates have anticholestatic, anti-inflammatory, and antifibrotic effects in animal and in-vitro studies. The mechanisms that underlie these effects are complementary, and largely mediated through activation of peroxisome proliferator activated receptors. Fibrate treatment ameliorated liver biochemical tests in UDCA unresponsive patients, either as mono-therapy or in combination with UDCA. These results, however, were obtained in case series and small pilot studies. The results of phase III studies, such as the Bezafibrate in Combination With Ursodeoxycholic Acid in Primary Biliary Cirrhosis (BEZURSO) trial, are currently awaited.

SUMMARY

A considerable body of observational evidence supports the safety and efficacy of fibrate treatment in PBC patients with an incomplete response to UDCA. These results encourage the evaluation of its effects on liver-related morbidity and mortality in larger clinical trials.

Diagnostic and clinical significance of anti-centromere antibodies in primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is an autoimmune disease of the liver characterised by biochemical evidence of cholestasis, elevated alkaline phosphatase levels and the presence of the highly disease specific anti-mitochondrial autoantibodies. Extra-hepatic autoimmune manifestations are common, including rheumatic disorders, such as systemic sclerosis (SSc). Notably, PBC is the most frequent autoimmune liver disease in SSc patients. Based on skin lesion extension, two major SSc disease subgroups are recognised: limited cutaneous SSc (lSSc) and diffuse cutaneous SSc. Anti-centromere antibody (ACA) positivity is highly characteristic of SSc, with up to 90% prevalence in lSSc patients. ACA has also been found in up to 30% of PBC patients and 80% of patients with a PBC/SSc overlap syndrome. The diagnostic and clinical significance of ACA positivity in patients with PBC without SSc has recently been under investigation, with several studies highlighting links to severe bile duct injury and portal hypertension. This review discusses the diagnostic and clinical relevance of ACA in patients with PBC, with or without SSc.

Questionnaire based assessment of risk factors for primary biliary cirrhosis

BACKGROUND

Primary biliary cirrhosis is a cholestatic liver disease characterized by immune-mediated destruction of bile ducts. Its pathogenesis is largely unknown, although complex interactions between environment and genetic predisposition are proposed.

AIMS

Identify disease risk factors using a detailed patient questionnaire and compare study findings to 3 published reports.

METHODS

Questionnaire data were prospectively collected from 522 cases and 616 controls of the Mayo Clinic Primary Biliary Cirrhosis Genetic Epidemiology Registry. Case and control responses were compared using logistic regression, adjusting for recruitment age, sex, and education level.

RESULTS

Cases reported ever regularly smoking cigarettes more frequently than controls (P < 0.001). History of urinary tract infection was similar between groups; however, cases reported multiple urinary tract infections more commonly than controls (P < 0.001). Frequency of other autoimmune disease was higher in cases than controls (P < 0.001). As well, prevalence of primary biliary cirrhosis among first-degree relatives was higher in case families than control families (P < 0.001).

CONCLUSIONS

Our study confirms prior reported risk factors associated with disease risk. Given the potential importance of gene and environment interactions, further examination of environmental risk factors considering genetic background may provide new insight into primary biliary cirrhosis pathogenesis.

Primary biliary cirrhosis: therapeutic advances

Primary biliary cirrhosis (PBC) is a chronic and slowly progressive cholestatic liver disease characterized by destruction of the interlobular bile ducts, which, if untreated, leads to fibrosis, biliary cirrhosis, and liver failure. Because liver transplantation remains the only curative option for PBC, the goals of treatment are to slow the rate of progression, to alleviate related symptoms, and to prevent complications. Ursodeoxycholic acid is the only US Food and Drug Administration-approved medical treatment of PBC. Several agents are undergoing evaluation as monotherapy or as an adjuvant to ursodeoxycholic acid. This review summarizes current therapeutic advances in the care of patients with PBC.

Risk factors for hepatic decompensation in patients with primary biliary cirrhosis

AIM: To examine the clinical features and analyze prognostic factors in a prospective study of primary biliary cirrhosis (PBC) patients.

METHODS: From 1995 to 2010, PBC patients without hepatic decompensation seen at the Peking Union Medical College Hospital were enrolled. Clinical signs and manifestations (pruritus, persistent fatigue, jaundice and pain in the right hypochondrium), laboratory parameters (auto-antibodies for autoimmune hepatic disease, biliary and hepatic enzymes, immunoglobulin, bilirubin, and albumin) and imaging findings were recorded at entry and at specific time points during follow-up. Cox regression and Kaplan-Meier analyses, respectively, assessed the risk factors for hepatic decompensation and survival.

RESULTS: Two hundred and sixty-two PBC patients were enrolled with a median follow-up of 75.2 mo (range, 21-201 mo). The 240 patients were aged 51.5 ± 10.2 years at diagnosis and 91.6% were female. Two hundred and forty-five (93.5%) were seropositive for anti-mitochondrial antibodies. At presentation, 170 patients (64.9%) were symptomatic, while 96 patients (36.6%) had extra-hepatic autoimmune disease. During the follow-up period, 62 (23.7%) patients developed hepatic decompensation of whom four underwent liver transplantation and 17 died. The cumulative survival rate and median survival time were 83.9% and 181.7 mo, respectively. Cox regression analysis revealed that an incomplete ursodeoxycholic acid (UDCA) response or inconsistent treatment [P < 0.001; hazard risk (HR) 95%CI = 2.423-7.541], anti-centromere antibodies (ACA) positivity (P < 0.001; HR 95%CI = 2.516-7.137), alanine aminotransferase ratio (AAR) elevations (P < 0.001; HR 95%CI = 1.357-2.678), and histological advanced liver disease (P = 0.006; HR 95%CI = 1.481-10.847) were predictors of hepatic decompensation. The clinical features and survival of PBC in China are consistent with those described in Western countries.

CONCLUSION: Incomplete UDCA response or inconsistent treatment, ACA positivity, AAR elevations, and advanced histological stage are predictors of decompensation.

Role of autoimmunity in primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is an autoimmune liver disease characterized by the presence of serum autoantibodies and chronic nonsuppurative destructive cholangitis. The pathogenesis of PBC involves environmental factors, genetic predisposition and loss of immune tolerance. In recent years, it has become univocally accepted that an inappropriately activated immune response is one of the most important factors in PBC. In this study, the role of autoimmunity in PBC is summarized and a feasible research orientation is recommended.

Primary biliary cirrhosis in Southern Israel: a 20 year follow up study

BACKGROUND

The epidemiology of primary biliary cirrhosis (PBC) in Israel is unknown. We aimed to determine the epidemiology, long-term survival and outcomes of PBC in Southern Israel from 1990 to 2010.

METHODS

Case-finding methods and population-based administrative data were used to estimate and evaluate the incidence, prevalence and prognostic factors of outcome in our PBC cohort.

RESULTS

138 cases of PBC were identified. The average annual prevalence of PBC was 255 cases per million. The overall age/sex-adjusted annual incidence of PBC was 10 cases per million from 1990 through 1999 and 20 cases per million from 2000 to 2010. Among 138 incident cases with a total follow-up of 960 persons-years from diagnosis, 30 patients (21.7%) died. Survival in PBC patients was significantly lower than that of the age/sex-matched Israeli population. Mortality was significantly increased in patients with an initial MELD score greater than 8 (P<0.001), with portal hypertension (P<0.001), and in non-responders to ursodeoxycholic acid (UDCA) therapy according to Barcelona criteria (P=0.005). Out of 138 patients, 95 patients (68.0%) responded to UDCA therapy according to Barcelona and Paris criteria. None of the responders died during the follow-up period as opposed to 30 out of 43 (69.8%) of non-responders. In multivariate analysis the factors associated with response to UDCA were: albumin levels above 3.5 g/dL (P<0.001) and lower degree of fibrosis per liver biopsy (P=0.003).

CONCLUSIONS

This study addresses the increasing burden of PBC in Israel and confirms the importance of some clinical and therapeutic factors as predictors of long-term prognosis.

Primary biliary cirrhosis: a multi-faced interactive disease involving genetics, environment and the immune response

Primary biliary cirrhosis (PBC) is considered a model autoimmune disease based on several features, including the presence of a highly directed and very specific immune response to mitochondrial autoantigens, a female predominance, a targeted destruction of the biliary epithelium, and homogeneity between patients. It is essentially a chronic progressive cholestatic liver disease characterized by immune-mediated destruction of small- and medium-sized intrahepatic bile ducts. There is considerable variation in the incidence and prevalence of the disease between regions of the world, although such differences likely reflect not only a true disparity in disease but also differences in awareness; for example, in the United States, PBC is often detected in an asymptomatic stage based on multi-phasic clinical testing. There has been considerable progress at defining the immune response in this disease, including quantitation of autoreactive T cells against PDC-E2, the major mitochondrial autoantigen. The overwhelming data suggests that patients develop PBC based on a genetic predisposition and loss of tolerance to one or more environmental agents. In this review, we will present an updated overview of PBC and place it in the context of autoimmunity.

Primary biliary cirrhosis and liver transplantation

Primary biliary cirrhosis (PBC) is an immune-mediated chronic progressive inflammatory liver disease, predominantly affecting middle-aged women, characterized by the presence of antimitochondrial antibodies (AMAs), which can lead to liver failure. Genetic contributions, environmental factors including chemical and infectious xenobiotics, autoimmunity and loss of tolerance have been aggressively investigated in the pathogenesis of PBC, however, the actual impact of these factors is still controversial. Survival of PBC patients has been largely improved with the widespread use of ursodeoxycholic acid (UDCA), however, one third of patients still do not respond to the treatment and proceed to liver cirrhosis, requiring liver transplantation as a last resort for cure. The outcome of liver transplantation is excellent with 5- and 10-year survival rates around 80% and 70%, respectively, while along with long survival, the recurrence of the disease has become an important outcome after liver transplantation. Prevalence rates of recurrent PBC rage widely between 1% and 35%, and seem to increase with longer follow-up. Center-specific issues, especially the use of protocol biopsy, affect the variety of incidence, yet, recurrence itself does not affect patient and graft survival at present, and retransplantation due to recurrent disease is extremely rare. With a longer follow-up, recurrent disease could have an impact on patient and graft survival.

Deletion of clock gene Per2 exacerbates cholestatic liver injury and fibrosis in mice

The Period 2 (Per2) gene is an important component of the circadian system and is thought to modulate many physiological and pathological processes in mammals. In the previous study, we have disclosed the protective role of Per2 against carbon tetrachloride induced liver injury and fibrosis. Here we further assess the effect of Per2 deficiency on cholestatic hepatic injury and fibrosis. Cholestasis was induced by bile duct ligation (BDL) for 10 days in wild-type (WT) and Per2(-/-) mice. Masson trichrome staining and analysis of α-SMA immunohistochemistry were performed to show the collagen accumulation and the HSC activation, respectively. The mRNA levels of fibrosis-related genes were monitored by quantitative real-time PCR. Following BDL, livers from Per2(-/-) mice exhibited markedly increased extent of bile infarct and extracellular matrix (ECM) deposition compared with WT mice. Furthermore, the expressions of fibrosis-related genes like TNF-α, TGF-β1, Col1α1 and TIMP-1 were dramatically elevated in Per2(-/-) cholestatic liver. Our observations indicated that clock gene Per2 plays a protective role in mediating liver injury and fibrosis during cholestasis.

Mitochondrial biogenesis fails in secondary biliary cirrhosis in rats leading to mitochondrial DNA depletion and deletions

Chronic cholestasis is characterized by mitochondrial dysfunction, associated with loss of mitochondrial membrane potential, decreased activities of respiratory chain complexes, and ATP production. Our aim was to determine the molecular mechanisms that link long-term cholestasis to mitochondrial dysfunction. We studied a model of chronic cholestasis induced by bile duct ligation in rats. Key sensors and regulators of the energetic state and mitochondrial biogenesis, mitochondrial DNA (mtDNA)-to-nuclear DNA (nDNA) ratio (mtDNA/nDNA) relative copy number, mtDNA deletions, and indexes of apoptosis (BAX, BCL-2, and cleaved caspase 3) and cell proliferation (PCNA) were evaluated. Our results show that long-term cholestasis is associated with absence of activation of key sensors of the energetic state, evidenced by decreased SIRT1 and pyruvate dehydrogenase kinase levels and lack of AMPK activation. Key mitochondrial biogenesis regulators (PGC-1α and GABP-α) decreased and NRF-1 was not transcriptionally active. Mitochondrial transcription factor A (TFAM) protein levels increased transiently in liver mitochondria at 2 wk after bile duct ligation, but they dramatically decreased at 4 wk. Reduced TFAM levels at this stage were mirrored by a marked decrease (65%) in mtDNA/nDNA relative copy number. The blockade of mitochondrial biogenesis should not be ascribed to activation of apoptosis or inhibition of cell proliferation. Impaired mitochondrial turnover and loss of the DNA stabilizing effect of TFAM are likely the causative event involved in the genetic instability evidenced by accumulation of mtDNA deletions. In conclusion, the lack of stimulation of mitochondrial biogenesis leads to mtDNA severe depletion and deletions in long-term cholestasis. Hence, long-term cholestasis should be considered a secondary mitochondrial hepatopathy.

Trends in liver transplantation for primary biliary cirrhosis in the Netherlands 1988-2008

Background

A decrease in the need for liver transplantations (LTX) in Primary Biliary Cirrhosis (PBC), possibly related to treatment with ursodeoxycholic acid (UDCA), has been reported in the USA and UK. The aim of this study was to assess LTX requirements in PBC over the past 20 years in the Netherlands.

Methods

Analysis of PBC transplant data of the Dutch Organ Transplant Registry during the period 1988-2008, including both absolute and proportional numbers. The indication for LTX was categorized as liver failure, hepatocellular carcinoma or poor quality of life (severe fatigue or pruritus). Data were analysed for two decades: 1.1.1988-31.12.1997 (1^st) and 1.1.1998-31.12.2007 (2^nd). The severity of disease was quantified using MELD scores. To fit lines which show trends over time we applied a linear regression model.

Results

A total of 110 patients (87% women) was placed on the waiting list. 105 patients were transplanted (1^st: 61, 2^nd: 44), 5 (5%) died while listed. The absolute annual number of LTX for PBC slightly decreased during the 20 year period, the proportional number decreased significantly. At the time of LTX the mean age was 53.6 yrs. (1^st: 53.4, 2^nd: 53.8), the mean MELD score 13.9 (1^st:14.5, 2^nd:13.0). The median interval from diagnosis to LTX was 90.5 months (1^st:86.5, 2^nd: 93.5). 69% of patients was treated with UDCA (1^st 38%, 2^nd 82%).

Conclusions

Over the past 20 years the absolute number of LTX for PBC in the Netherlands showed a tendency to decrease whereas the proportional decrease was significant. There was a trend over time toward earlier transplantation.

Primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is an idiopathic chronic autoimmune liver disease that primarily affects women. It is believed that the aetiology for PBC is a combination between environmental triggers in genetically vulnerable persons. The diagnosis for PBC is made when two of the three criteria are fulfilled and they are: (1) biochemical evidence of cholestatic liver disease for at least 6 month's duration; (2) anti-mitochondrial antibody (AMA) positivity; and (3) histologic features of PBC on liver biopsy. Ursodeoxycholic acid (UDCA) is the only FDA-approved medical treatment for PBC and should be administered at a recommended dose of 13-15 mg/kg/day. Unfortunately despite adequate dosing of UDCA, approximately one-third of patients does not respond adequately and may require liver transplantation. Future studies are necessary to elucidate the role of environmental exposures and overall genetic impact not only in the development of PBC, but on disease progression and variable clinical response to therapy.

Update on primary biliary cirrhosis

Primary biliary cirrhosis is an autoimmune chronic liver disease characterized by progressive bile duct destruction eventually leading to cirrhosis, liver failure, and death. The autoimmune pathogenesis is supported by a plethora of experimental and clinical data, such as the presence of autoreactive T cells and serum autoantibodies. The aetiology remains unknown, although evidence suggests a role for both genetic susceptibility and environmental factors that remain to be determined. In fact, a number of chemicals and infectious agents have been proposed to induce the disease in predisposed individuals. The recent availability of several murine models will significantly help in understanding pathophysiology mechanisms. In this review, we critically summarize the most recent data on the aetiopathogenesis of primary biliary cirrhosis, discuss the latest theories and developments, and suggest directions for future research.

Bezafibrate treatment of primary biliary cirrhosis following incomplete response to ursodeoxycholic acid

BACKGROUND AND GOALS

Ursodeoxycholic acid (UDCA) is the only current pharmacologic treatment for primary biliary cirrhosis (PBC). However, some patients show persistent liver biochemical abnormalities even after 6 to 12 months treatment. Bezafibrate retard is a commonly used medication for hyperlipidemia. In Japanese studies, it was found to lower liver enzyme levels, apparently through its action on multiple drug resistance gene 3, a transport element of the ATP-dependent bile secretion system, and on peroxisome proliferator-activated receptor-alpha. The aim of this study was to evaluate the effect of adding bezafibrate to the treatment regimen in patients with PBC and a partial response to UDCA.

STUDY

The study group included 8 White patients, 7 women and 1 man, aged 52 to 76 years with PBC who had been treated at our Liver Institute with UDCA (900 mg/d to 1500 mg/d) for 2 to 11 years (mean, 5.7 y) with only a partial response (19% to 56% reduction in alkaline phosphatase level). Bezafibrate (400 mg/d) was added to UDCA and the patients were followed for 4 to 12 months.

RESULTS

Alkaline phosphatase levels (normal range, 35 to 104 U/L) decreased in all patients, from 140 to 360 U/L (mean, 201.2) to 68 to 158 U/L (mean, 98.4), and normalized in 6 patients. In addition, levels of gamma-glutamyl transferase (normal range, 6 to 42 U/L) decreased from 70 to 192 U/L (mean, 130) to 41 to 122 U/L (mean, 71.8). These findings were maintained throughout follow-up.

CONCLUSIONS

Combination therapy with bezafibrate and UDCA improves the biochemical profile of patients with PBC who respond only partially to UDCA. A larger controlled study is needed to evaluate the clinical implications of these findings.

Genomic variants associated with primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is an autoimmune hepatobiliary disease characterized by immune-mediated injury of small and medium-sized bile ducts, eventually leading to liver cirrhosis. Several studies have addressed PBC immunopathology, and the data support an immune activation leading to autoantibodies and autoreactive T cells acting against the lipoylated 2-oxoacid dehydrogenase complexes. The causes of the disease remain unknown, but environmental factors and genetic susceptibility both contribute to its onset. Over the past two decades several association studies have addressed the role of genetic polymorphisms in PBC pathogenesis and have reported multiple associations. However, only a few studies had sufficient statistical power, and in most cases results were not independently validated. A genome-wide association study has recently been reported, but this too awaits independent confirmation. The aim of this present work is to critically review the numerous studies dedicated to revealing genetic associations in PBC, and to predict the potential for future studies based on these data.

Assessment of liver fibrosis and steatosis in PBC with FibroScan, MRI, MR-spectroscopy, and serum markers

BACKGROUND

In recent years noninvasive methods have been evaluated for the assessment of liver fibrosis predominantly in patients with viral hepatitis. In this study, transient elastography (FibroScan), magnetic resonance imaging (MRI), magnetic resonance (MR)-spectroscopy, and serum markers were compared in patients with primary biliary cirrhosis (PBC) for the assessment of liver fibrosis and steatosis.

METHODS

Forty-five patients with PBC and histologic assessment of liver fibrosis received transient elastography and examinations for serum markers of fibrosis and steatosis. In addition, 41 out of 45 patients received contrast-enhanced MRI and 38 out of 45 patients received proton MR-spectroscopy.

RESULTS

The adjusted accuracy (area under the receiver operating characteristic) for the diagnosis of histologic-stage > or = II for FibroScan, MRI-contrast enhancement and Forns index was 80%, 83%, and 69%, and for the diagnosis of liver cirrhosis 95%, 91%, and 94%, respectively. No correlation of histologic-stage was observed for FibroTest and AST to platelet ratio index. Histologic steatosis significantly correlated with body mass index (r=0.46), the SteatoTest (r=0.39), homeostasis model assessment of insulin resistance (r=0.46), and MR-spectroscopy (r=-0.76). The accuracy for the diagnosis of histologic steatosis was best with MR-spectroscopy (88%).

CONCLUSIONS

Contrast-enhanced MRI and FibroScan can be used with comparable results for the assessment of liver fibrosis in patients with PBC and seem to supplement each other. MR-spectroscopy represents the best method for highly accurate noninvasive measurement of liver steatosis.

Experimental evidence on the immunopathogenesis of primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is a chronic cholestatic liver disease for which an autoimmune pathogenesis is supported by clinical and experimental data, including the presence of autoantibodies and autoreactive T cells. The etiology remains to be determined, yet data suggest that both a susceptible genetic background and unknown environmental factors determine disease onset. Multiple infectious and chemical candidates have been proposed to trigger the disease in a genetically susceptible host, mostly by molecular mimicry. Most recently, several murine models have been reported, including genetically determined models as well as models induced by immunization with xenobiotics and bacteria.

Predictive value of aspartate aminotransferase to alanine aminotransferase ratio for hepatic fibrosis and clinical adverse outcomes in patients with primary biliary cirrhosis

BACKGROUND

The aspartate aminotransferase to alanine aminotransferase ratio (AAR) was seldom applied for fibrosis assessment in primary biliary cirrhosis (PBC) patients.

GOALS

To validate the AAR for evaluating hepatic fibrosis, disease severity, and prognosis in patients with PBC.

STUDY

Ninety-two consecutive PBC patients were retrospectively evaluated to validate the AAR for assessing the severity of liver function, the degrees of hepatic fibrosis, and predicting outcomes.

RESULTS

AAR showed modest correlations to Mayo score, model for end-stage liver disease score, and Child-Pugh score (r2=0.156,P<0.001; r2=0.084, P=0.005; r2=0.142, P<0.001, respectively)in evaluating the severity of liver function. For 46 patients who underwent liver biopsy, 35 were in early stage fibrosis and the other 11 were in advanced fibrosis. AAR was significantly higher in patients with advanced fibrosis than those with early fibrosis (mean+/-standard deviation; 1.40+/-0.44 vs. 0.98+/-0.65,P=0.001). The AAR yielded the highest area under the receiver operating curve of 0.847 than Mayo score, model for end-stage liver disease score, and Child-Pugh score in predicting advanced fibrosis. During a median follow-up of 44.5 months, 24 patients expired and 68 patients were alive. Patients with an AAR of 1 or less had significantly better prognosis than their counterparts(P=0.043).

CONCLUSIONS

AAR is a simple and reliable marker to assess liver function and hepatic fibrosis as well as to predict outcomes in PBC patients.

Primary Biliary Cirrhosis-Related Autoimmune Hemolytic Anemia: Three Case Reports and Review of the Literature

The association between primary biliary cirrhosis (PBC) and autoimmune hemolytic anemia (AIHA) is uncommon; only fourteen such case reports have been described. In this report, three patients who developed AIHA on the basis of PBC underwent successful therapy with corticosteroids and ursodeoxycholic acid (UDCA). Patient 3 was more complicated, suffering from PBC, Evans syndrome, Sjögren syndrome and Klinefelter syndrome simultaneously. This has not previously been reported in the world literature. Review of all fifteen cases showed that there is a prominent occurrence sequence that AIHA might take place on the basis of PBC. With sufficient doses of corticosteroids or immunosuppressant therapy, besides hemolysis under effective control, liver function also improved. According to the criteria of secondary AIHA, we may call them PBC-related AIHA. Thus, patients with PBC with serum bilirubin levels rising suddenly should undergo screening for associated hemolysis. Recommended treatment for PBC-related AIHA includes sufficient doses of corticosteroids to control the hemolysis in the acute phase, and immunosuppressant or adequate dose of UDCA to maintain therapy. These case reports have been increasing in recent years, so further reserch is needed to illustrate the incidence and natural courses of these two organ-specific autoimmune diseases.

Keratin variants are overrepresented in primary biliary cirrhosis and associate with disease severity

Keratins (K) 8 and 18 variants predispose carriers to the development of end-stage liver disease and patients with chronic hepatitis C to disease progression. Hepatocytes express K8/K18, whereas biliary epithelia express K8/K18/K19. K8-null mice, which are predisposed to liver injury, spontaneously develop anti-mitochondrial antibodies (AMA) and have altered hepatocyte mitochondrial size and function. There is no known association of K19 with human disease and no known association of K8/K18/K19 with human autoimmune liver disease. We tested the hypothesis that K8/K18/K19 variants associate with primary biliary cirrhosis (PBC), an autoimmune cholestatic liver disease characterized by the presence of serum AMA. In doing so, we analyzed the entire exonic regions of K8/K18/K19 in 201 Italian patients and 200 control blood bank donors. Five disease-associated keratin heterozygous variants were identified in patients versus controls (K8 G62C/R341H/V380I, K18 R411H, and K19 G17S). Four variants were novel and included K19 G17S/V229M/N184N and K18 R411H. Overall, heterozygous disease-associated keratin variants were found in 17 of 201 (8.5%) PBC patients and 4 of 200 (2%) blood bank donors (P < 0.004, odds ratio = 4.53, 95% confidence interval = 1.5-13.7). Of the K19 variants, K19 G17S was found in three patients but not in controls and all K8 R341H (eight patients and three controls) associated with concurrent presence of the previously described intronic K8 IVS7+10delC deletion. Notably, keratin variants associated with disease severity (12.4% variants in Ludwig stage III/IV versus 4.2% in stages I/II; P < 0.04, odds ratio = 3.25, 95% confidence interval = 1.02-10.40), but not with the presence of AMA.

CONCLUSION

K8/K18/K19 variants are overrepresented in Italian PBC patients and associate with liver disease progression. Therefore, we hypothesize that K8/K18/K19 variants may serve as genetic modifiers in PBC.

Primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is an immune-mediated chronic cholestatic liver disease with a slowly progressive course. Without treatment, most patients eventually develop fibrosis and cirrhosis of the liver and may need liver transplantation in the late stage of disease. PBC primarily affects women (female preponderance 9–10:1) with a prevalence of up to 1 in 1,000 women over 40 years of age. Common symptoms of the disease are fatigue and pruritus, but most patients are asymptomatic at first presentation. The diagnosis is based on sustained elevation of serum markers of cholestasis, i.e., alkaline phosphatase and gamma-glutamyl transferase, and the presence of serum antimitochondrial antibodies directed against the E2 subunit of the pyruvate dehydrogenase complex. Histologically, PBC is characterized by florid bile duct lesions with damage to biliary epithelial cells, an often dense portal inflammatory infiltrate and progressive loss of small intrahepatic bile ducts. Although the insight into pathogenetic aspects of PBC has grown enormously during the recent decade and numerous genetic, environmental, and infectious factors have been disclosed which may contribute to the development of PBC, the precise pathogenesis remains enigmatic. Ursodeoxycholic acid (UDCA) is currently the only FDA-approved medical treatment for PBC. When administered at adequate doses of 13–15 mg/kg/day, up to two out of three patients with PBC may have a normal life expectancy without additional therapeutic measures. The mode of action of UDCA is still under discussion, but stimulation of impaired hepatocellular and cholangiocellular secretion, detoxification of bile, and antiapoptotic effects may represent key mechanisms. One out of three patients does not adequately respond to UDCA therapy and may need additional medical therapy and/or liver transplantation. This review summarizes current knowledge on the clinical, diagnostic, pathogenetic, and therapeutic aspects of PBC.

Clinical features and management of primary biliary cirrhosis

Primary biliary cirrhosis (PBC), which is characterized by progressive destruction of intrahepatic bile ducts, is not a rare disease since both prevalence and incidence are increasing during the last years mainly due to the improvement of case finding strategies. The prognosis of the disease has improved due to both the recognition of earlier and indolent cases, and to the wide use of ursodeoxycholic acid (UDCA). New indicators of prognosis are available that will be useful especially for the growing number of patients with less severe disease. Most patients are asymptomatic at presentation. Pruritus may represent the most distressing symptom and, when UDCA is ineffective, cholestyramine represents the mainstay of treatment. Complications of long-standing cholestasis may be clinically relevant only in very advanced stages. Available data on the effects of UDCA on clinically relevant end points clearly indicate that the drug is able to slow but not to halt the progression of the disease while, in advanced stages, the only therapeutic option remains liver transplantation.

Treatment of primary biliary cirrhosis: therapy with choleretic and immunosuppressive agents

Primary biliary cirrhosis (PBC) is a chronic cholestatic liver disease of presumed autoimmune etiology affecting predominantly middle-aged women; it is a slowly progressive disease causing loss of intrahepatic bile ducts, resulting in advanced fibrosis, cirrhosis, and liver failure. Many drugs have been studied for treatment, including agents with choleretic and immunosuppressive properties. Ursodeoxycholic acid (UDCA) has been evaluated most widely. After liver failure, the only effective treatment is liver transplantation. Effective therapy reduces the need for transplantation and improves life expectancy. For advanced liver disease or incomplete response to UDCA, new therapies to cure or retard the progression of disease in PBC are needed.

Recent advances in the epidemiology of primary biliary cirrhosis

Since initial reports in the mid-1970s provided epidemiology data on primary biliary cirrhosis (PBC), many studies have characterized the variable frequency of this disease in diverse populations worldwide and sought to identify associated risk factors. Recent research confirms earlier work suggesting that the incidence and prevalence of PBC are on the rise, although geographic variation persists. Analysis of familial and geographic clustering supports the hypothesis that development and progression of the disease hinge on a complex interplay between genetic and environmental risk factors. International clinical data systems are needed to advance PBC epidemiologic research. Given this complexity, international clinical data systems are needed to advance PBC epidemiologic research.

TRAIL mediates liver injury by the innate immune system in the bile duct-ligated mouse

The contribution of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), a death ligand expressed by cells of the innate immune system, to cholestatic liver injury has not been explored. Our aim was to ascertain if TRAIL contributes to liver injury in the bile duct-ligated (BDL) mouse. C57/BL6 wild-type (wt), TRAIL heterozygote (TRAIL(+/-)), and TRAIL knockout (TRAIL(-/-)) mice were used for these studies. Liver injury and fibrosis were examined 7 and 14 days after BDL, respectively. Hepatic TRAIL messenger RNA (mRNA) was 6-fold greater in BDL animals versus sham-operated wt animals (P < 0.01). The increased hepatic TRAIL expression was accompanied by an increase in liver accumulation of natural killer 1.1 (NK 1.1)-positive NK and natural killer T (NKT) cells, the predominant cell types expressing TRAIL. Depletion of NK 1.1-positive cells reduced hepatic TRAIL mRNA expression and serum alanine aminotransferase (ALT) values. Consistent with a role for NK/NKT cells in this model of liver injury, stress ligands necessary for their recognition of target cells were also up-regulated in hepatocytes following BDL. Compared to sham-operated wt mice, BDL mice displayed a 13-fold increase in terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) and an 11-fold increase in caspase 3/7-positive hepatocytes (P < 0.01). The number of TUNEL and caspase 3/7-positive cells was reduced by >80% in BDL TRAIL knockout animals (P < 0.05). Likewise, liver histology, number of bile infarcts, serum ALT values, hepatic fibrosis, and animal survival were also improved in BDL TRAIL(-/-) animals as compared to wt animals.

CONCLUSION

These observations support a pivotal role for TRAIL in cholestatic liver injury mediated by NK 1.1-positive NK/NKT cells.

Medical treatment of cholestatic liver disease

In most cholestatic liver diseases the cause of the disease is not known and therapy can only be directed toward suppression of the pathogenetic processes and amelioration of the consequences of cholestasis. The recognition of adaptive-compensatory responses to cholestasis has become of major importance. They tend to minimize retention of bile acids and other potentially toxic solutes in the hepatocyte by limiting hepatocellular uptake, reducing bile acid synthesis, stimulating detoxification, and up-regulating alternative pathways for excretion. Some of the drugs used for the treatment of cholestatic liver diseases in an empiric way turned out to be modulators of nuclear receptors, which regulate these adaptive-compensatory responses. New drugs are being designed and tested along these lines and may be regarded as treatment opportunities of the future.

Quantification of antineural antibodies in autoimmune neurological disorders

More than 50 different neurological pathologies have a confirmed or suspected autoimmune etiology affecting an estimated number of 75 million people worldwide. Autoantibodies are a useful diagnostic marker for most autoimmune diseases even though their pathological role is not evident, and several tests for their detection are commercially available. However, for autoimmune diseases involving the nervous system, lack of clear information on the identity of antineural antibody targets and the presence of many rare diseases have hampered the development of specific diagnostic assays. This review focuses on the actual knowledge on confirmed and suspected autoimmune diseases that target the CNS and the diagnostic relevance of corresponding antineural autoantibodies.