Palak J. Trivedi

Review article: overlap syndromes and autoimmune liver disease

Autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) all nestle within the family of autoimmune liver diseases, whereby the result of immune‐mediated liver injury gives rise to varied clinical presentations. Some patients demonstrate a phenotype whereby there is evidence of either PBC or PSC together with overlapping features of AIH. Due to an absence of well‐validated diagnostic criteria and a lack of large therapeutic trials, treatment of overlap conditions is empiric and extrapolated from data derived from the primary autoimmune liver diseases.

Stratification of hepatocellular carcinoma risk in primary biliary cirrhosis: a multicentre international study

Objective Hepatocellular carcinoma (HCC) is an infrequent yet critical event in primary biliary cirrhosis (PBC); however, predictive tools remain ill-defined. Our objective was to identify candidate risk factors for HCC development in patients with PBC. Design Risk factor analysis was performed in over 15 centres from North America and Europe spanning >40 years observation period using Cox proportional hazards assumptions, logistic regression, and Kaplan-Meier estimates. Results Of 4565 patients with PBC 123 developed HCC, yielding an incidence rate (IR) of 3.4 cases/1000 patient-years. HCC was significantly more common in men (p<0.0001), and on univariate analysis factors at PBC diagnosis associated with future HCC development were male sex (unadjusted HR 2.91, p<0.0001), elevated serum aspartate transaminase (HR 1.24, p<0.0001), advanced disease (HR 2.72, p=0.022), thrombocytopenia (HR 1.65, p<0.0001), and hepatic decompensation (HR 9.89, p<0.0001). As such, non-treatment with ursodeoxycholic acid itself was not associated with cancer development; however, 12-month stratification by biochemical non-response (Paris-I criteria) associated significantly with future risk of HCC (HR 4.52, p<0.0001; IR 6.6 vs 1.4, p<0.0001). Non-response predicted future risk in patients with early stage disease (IR 4.7 vs 1.2, p=0.005), advanced disease (HR 2.79, p=0.02; IR 11.2 vs 4.4, p=0.033), and when restricting the analysis to only male patients (HR 4.44, p<0.001; IR 18.2 vs 5.4, p<0.001). On multivariable analysis biochemical non-response remained the most significant factor predictive of future HCC risk (adjusted HR 3.44, p<0.0001). Conclusions This uniquely powered, internationally representative cohort robustly demonstrates that 12-month biochemical non-response is associated with increased future risk of developing HCC in PBC. Such risk stratification is relevant to patient care and development of new therapies.

Optimising risk stratification in primary biliary cirrhosis: AST/platelet ratio index predicts outcome independent of ursodeoxycholic acid response

BACKGROUND & AIMS Outcomes in primary biliary cirrhosis (PBC) can be predicted by biochemical response to ursodeoxycholic acid (UDCA). Such stratification inadequately captures cirrhosis/portal hypertension, recognised factors associated with adverse events. METHODS We evaluated a cohort of PBC patients (n=386) attending the Liver Unit in Birmingham (derivation cohort), seeking to identify risk-variables associated with transplant-free survival independent of UDCA-response. A validation cohort was provided through well-characterised patients attending the Toronto Center for Liver Diseases (n=479) and Jena University Hospital (n=150). RESULTS On multivariate analysis, factors at diagnosis associated with liver transplant (LT)/death were patient age (HR:1.06; p<0.001), elevated bilirubin (HR:1.27; p<0.001), early-onset cirrhosis (HR:2.40; p<0.001) and baseline AST/platelet ratio index (APRI) (HR:1.95; p<0.001). At 1-year, UDCA biochemical non-response predicted poorer transplant-free survival, and additional factors (multivariate) associated with adverse outcome were age (HR:1.02; p<0.05) and 1-year APRI (HR:1.15; p<0.001). Obtaining a cut-point from our derivation cohort, APRI >0.54 at baseline was predictive of LT/death (adjusted HR: 2.40; p<0.001), and retained statistical significance when applied at 1-year (APRI-r1, adjusted HR:2.75; p<0.001) despite controlling for UDCA-response. Across both cohorts, transplant-free survival was poorer for biochemical-responders with an APRI-r1 >0.54 vs. biochemical-responders with a lower APRI-r1 (p<0.01 and p<0.001, respectively); non-responders with high APRI-r1 had the poorest outcomes (p<0.001 and p<0.001). CONCLUSION In PBC, elevated APRI is associated with future risk of adverse events, independently and additively of UDCA-response. This cross-centre, robustly validated observation will contribute to ongoing efforts to refine existing risk-stratification tools, as well as direct focus for new therapies in patients with PBC.

Relaxin modulates human and rat hepatic myofibroblast function and ameliorates portal hypertension in vivo.

Active myofibroblast (MF) contraction contributes significantly to the increased intrahepatic vascular resistance that is the primary cause of portal hypertension (PHT) in cirrhosis. We sought proof of concept for direct therapeutic targeting of the dynamic component of PHT and markers of MF activation using short‐term administration of the peptide hormone relaxin (RLN). We defined the portal hypotensive effect in rat models of sinusoidal PHT and the expression, activity, and function of the RLN‐receptor signaling axis in human liver MFs. The effects of RLN were studied after 8 and 16 weeks carbon tetrachloride intoxication, following bile duct ligation, and in tissue culture models. Hemodynamic changes were analyzed by direct cannulation, perivascular flowprobe, indocyanine green imaging, and functional magnetic resonance imaging. Serum and hepatic nitric oxide (NO) levels were determined by immunoassay. Hepatic inflammation was assessed by histology and serum markers and fibrosis by collagen proportionate area. Gene expression was analyzed by quantitative reverse‐transcription polymerase chain reaction (qRT‐PCR) and western blotting and hepatic stellate cell (HSC)‐MF contractility by gel contraction assay. Increased expression of RLN receptor (RXFP1) was shown in HSC‐MFs and fibrotic liver diseases in both rats and humans. RLN induced a selective and significant reduction in portal pressure in pathologically distinct PHT models, through augmentation of intrahepatic NO signaling and a dramatic reduction in contractile filament expression in HSC‐MFs. Critical for translation, RLN did not induce systemic hypotension even in advanced cirrhosis models. Portal blood flow and hepatic oxygenation were increased by RLN in early cirrhosis. Treatment of human HSC‐MFs with RLN inhibited contractility and induced an antifibrogenic phenotype in an RXFP1‐dependent manner. Conclusion: We identified RXFP1 as a potential new therapeutic target for PHT and MF activation status. (Hepatology 2014;59:1492‐1504)

PSC, AIH and overlap syndrome in inflammatory bowel disease

Primary sclerosing cholangitis (PSC) is a progressive, cholestatic disorder characterised by chronic inflammation and stricture formation of the biliary tree. Symptoms include pruritus, fatigue and in advanced cases ascending cholangitis, cirrhosis and end-stage hepatic failure. Patients are at an increased risk of malignancy arising from the bile ducts, gallbladder, liver and colon. The majority (>80%) of Northern European patients with PSC also have inflammatory bowel disease (IBD), usually ulcerative colitis (UC). IBD commonly presents before the onset of PSC, although the opposite can occur and the onset of both conditions can be separated by many years. The colitis associated with PSC is characteristically mild although frequently involves the whole colon. Despite the majority of patients having relatively inactive colonic disease, paradoxically the risk of colorectal malignancy is substantially increased. Patients may also develop dominant, stenotic lesions of the biliary tree which may be difficult to differentiate from cholangiocarcinoma and the coexistence of IBD may influence the development of this complication. Ursodeoxycholic acid may offer a chemoprotective effect against colorectal malignancy and improve liver biochemical indices. Evidence of any beneficial effect on histological progression of hepatobiliary disease is less clear. High doses (∼25-30 mg/kg/d) may be harmful and should be avoided. Autoimmune hepatitis (AIH) is less common in patients with IBD than PSC, however, an association has been observed. A small subgroup may have an overlap syndrome between AIH and PSC and management should be individualised dependant on liver histology, serum immunoglobulin levels, autoantibodies, degree of biochemical cholestasis and cholangiography.

The gut-adherent microbiota of PSC-IBD is distinct to that of IBD.

Primary sclerosing cholangitis–IBD (PSC–IBD) is an inflammatory autoimmune hepato–biliary–enteric disease in which it is predicted that gut microbiota have potential pathophysiological effects, relevant to disease initiation and outcome. The recent article by Kummen et al 1 who reported that the gut microbiota in PSC is distinct compared with those from healthy controls and patients with UC without liver disease, is therefore of interest. However, it remains unclear if these alterations in the gut microbiota are a cause or an effect of liver disease, and there remains a challenging task to link dysbiosis with disease pathogenesis, as well as clarify whether faecal microbiota are entirely representative of communities of mucosa-associated bacteria, which might uniquely interact with immune and epithelial cells. Nevertheless Kummen et al notably demonstrated that the Veillonella genus showed a marked increase in PSC–IBD, in comparison with both healthy controls and patients with UC alone. Given interest in the mechanism of lymphocyte tracking between the bowel and liver …

Good Maternal and Fetal Outcomes for Pregnant Women With Primary Biliary Cirrhosis

BACKGROUND & AIMS Up to 25% of patients diagnosed with primary biliary cirrhosis (PBC) are of childbearing age. However, little is known about disease course during pregnancy. METHODS We performed a retrospective analysis of women with PBC during pregnancy using a representative large cohort of patients attending the Liver Center at Toronto Western hospital from January 1979 through June 2009 (n = 306). Statistical analysis was performed by using R statistical software. RESULTS We identified 32 women (50 pregnancies) who either became pregnant after a diagnosis of PBC or in whom pregnancy led to diagnosis. Liver biochemistry remained stable in most patients (70%) throughout pregnancy. However, 23 of 32 patients (72%) had a flare in biochemical disease activity post partum, which was unrelated to biochemical disease activity before conception (P = .53), or during the gestational period (P = .14). No adverse maternal events were observed during pregnancy or post partum, and only 2 of 32 of women (6%) developed progressive disease after delivery. De novo pruritus developed during pregnancy in 17 of 32 women (53%), whereas itch that existed before conception worsened for 4 patients. Fifteen of 21 women (71%) with pregnancy-related pruritus required symptom-specific therapy. Twenty-nine of 32 women (91%) had at least 1 successful live birth; adverse fetal outcome was not influenced by biochemical disease activity before conception (P = .24) or during pregnancy (P = 1.00). CONCLUSION Pregnancy in women with PBC is frequently symptomatic but mostly uneventful. The majority of women maintain stable liver biochemistry during pregnancy, although postpartum biochemical exacerbations are common.

Risk stratification in autoimmune cholestatic liver diseases: Opportunities for clinicians and trialists

Primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) are infrequent autoimmune cholestatic liver diseases, that disproportionate to their incidence and prevalence, remain very important causes of morbidity and mortality for patients with liver disease. Mechanistic insights spanning genetic risks and biological pathways to liver injury and fibrosis have led to a renewed interest in developing therapies beyond ursodeoxycholic acid that are aimed at both slowing disease course and improving quality of life. International cohort studies have facilitated a much greater understanding of disease heterogeneity, and in so doing highlight the opportunity to provide patients with a more individualized assessment of their risk of progressive liver disease, based on clinical, laboratory, or imaging findings. This has led to a new approach to patient care that focuses on risk stratification (both high and low risk); and furthermore allows such stratification tools to help identify patient subgroups at greatest potential benefit from inclusion in clinical trials. In this article, we review the applicability and validity of risk stratification in autoimmune cholestatic liver disease, highlighting strengths and weaknesses of current and emergent approaches. (Hepatology 2016;63:644–659)

Treatment of autoimmune liver disease: current and future therapeutic options.

Autoimmune liver disease spans three predominant processes, from the interface hepatitis of autoimmune hepatitis to the lymphocytic cholangitis of primary biliary cirrhosis, and finally the obstructive fibrosing sclerotic cholangiopathy of primary sclerosing cholangitis. Although all autoimmune in origin, they differ in their epidemiology, presentation and response to immunosuppressive therapy and bile acid based treatments. With an ongoing better appreciation of disease aetiology and pathogenesis, treatment is set ultimately to become more rational. We provide an overview of current and future therapies for patients with autoimmune liver disease, with an emphasis placed on some of the evidence that drives current practice.

norUrsodeoxycholic acid improves cholestasis in primary sclerosing cholangitis

BACKGROUND & AIM Primary sclerosing cholangitis (PSC) represents a devastating bile duct disease, currently lacking effective medical therapy. 24-norursodeoxycholic acid (norUDCA) is a side chain-shortened C23 homologue of UDCA and has shown potent anti-cholestatic, anti-inflammatory and anti-fibrotic properties in a preclinical PSC mouse model. A randomized controlled trial, including 38 centers from 12 European countries, evaluated the safety and efficacy of three doses of oral norUDCA (500mg/d, 1,000mg/d or 1,500mg/d) compared with placebo in patients with PSC. METHODS One hundred sixty-one PSC patients without concomitant UDCA therapy and with elevated serum alkaline phosphatase (ALP) levels were randomized for a 12-week treatment followed by a 4-week follow-up. The primary efficacy endpoint was the mean relative change in ALP levels between baseline and end of treatment visit. RESULTS norUDCA reduced ALP levels by -12.3%, -17.3%, and -26.0% in the 500, 1,000, and 1,500mg/d groups (p=0.029, p=0.003, and p<0.0001 when compared to placebo), respectively, while a +1.2% increase was observed in the placebo group. Similar dose-dependent results were found for secondary endpoints, such as ALT, AST, γ-GT, or the rate of patients achieving ALP levels <1.5× ULN. Serious adverse events occurred in seven patients in the 500mg/d, five patients in the 1,000mg/d, two patients in the 1500mg/d group, and three in the placebo group. There was no difference in reported pruritus between treatment and placebo groups. CONCLUSIONS norUDCA significantly reduced ALP values dose-dependently in all treatment arms. The safety profile of norUDCA was excellent and comparable to placebo. Consequently, these results justify a phase III trial of norUDCA in PSC patients. Lay summary: Effective medical therapy for primary sclerosing cholangitis (PSC) is urgently needed. In this phase II clinical study in PSC patients, a side chain-shortened derivative of ursodeoxycholic acid, norursodeoxycholic acid (norUDCA), significantly reduced serum alkaline phosphatase levels in a dose-dependent manner during a 12-week treatment. Importantly, norUDCA showed a favorable safety profile, which was similar to placebo. The use of norUDCA in PSC patients is promising and will be further evaluated in a phase III clinical study. ClinicalTrials.gov number: NCT01755507.