Retrospective review of pediatric and adult autoimmune hepatitis in two quaternary care centres in British Columbia: increased prevalence seen in British Columbia's First Nations community

Current practice in the management of paediatric autoimmune liver disease in Europe

OBJECTIVE

Paediatric autoimmune liver disease (pAILD) is a rare condition with serious health implications. Notwithstanding treatment advancements, areas of uncertainty and knowledge gaps still exist. We here investigated the real-life approach to pAILD management in Europe.

METHODS

A survey was distributed to members of the European Rare Liver Disease Reference Network (ERN RARE-LIVER) and the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) Hepatology Interest Group. Information was gathered regarding clinical activity, medications used, and access to paediatric drug formulations at each site.

RESULTS

Thirty-six centres from 22 European countries responded to the survey. The majority are exclusively paediatric units (86%). Among participants, 80% follow <50 children with pAILD, of which 25%-50% are <10 years old in 44% of centres. All centres use predniso(lo)ne as first-line therapy, alone (15/36) or with azathioprine (21/36). Azathioprine and mycophenolate are the preferred second-line options in centres using first-line steroid monotherapy (11/15) or combined steroid-azathioprine (19/21), respectively. Tacrolimus is used as third-line agent in 15/36 centres. Proactive measurement of drug metabolites and target levels vary widely among centres. Paediatric predniso(lo)ne formulations are commercially available in 7/22 European countries, azathioprine in 3, mycophenolate in 14, tacrolimus in 15 and ursodeoxycholic acid in 14. When paediatric formulations are unavailable, children are treated with magisterial preparations or 'solid' formulations (crushed or intact).

CONCLUSIONS

Treatment of pAILD in Europe varies widely in terms of medications used and treatment monitoring. Availability of paediatric drug formulations across Europe is limited. Collaborative initiatives are needed to define evidence-based strategies for management of pAILD and to promote an equal, age-appropriate treatment for affected children.

The Epidemiology of Pediatric Autoimmune Hepatitis in Scotland: A National Cohort Study

Autoimmune hepatitis (AIH) is a rare, but potentially severe, cause of liver disease in children. We aimed to summarize how children with AIH in Scotland presented, were investigated and managed in addition to producing novel epidemiological data and outcomes.

Methods

All prevalent pediatric patients with AIH cared for in pediatric services between January 2013 and September 2018 were included. Individual patient data were obtained from electronic patient records in the 3-main academic pediatric centers in Scotland covering the entire population.

Results

Thirty-eight patients were included (25 female) with median follow-up of 33 months (range, 2-145 mo) and 136 total patient years. The incidence between 2014 and 2017 was 0.49/100 000/y (95% confidence interval, 0.29-0.78) and point prevalence between 2013 and 2018 was 1.75/100 000 (95% confidence interval, 1.42-2.13). Thirty-five (92%) patients were autoantibody positive, most commonly anti-nuclear antibody (63%) and anti-smooth muscle antibody (42%). Thirty-seven (97%) patients had induction therapy with oral corticosteroids, 30 (79%) required maintenance treatment with azathioprine, and 23 (61%) received ursodeoxycholic acid. There were 1.4 disease flares per 10 patient years and 3 patients required liver transplantation with an overall 5-year survival rate without the need for transplantation of 95%.

Conclusions

We calculated a novel incidence and prevalence rate for pediatric AIH in Scotland. Nearly all were invariably treated initially with corticosteroids with most placed-on azathioprine as maintenance therapy. Outcomes were generally favorable with low rates of disease flares and the need for transplantation being rare.

Pediatric Autoimmune Liver Diseases: Autoimmune Hepatitis and Primary Sclerosing Cholangitis

In chronic hepatitis, a broad differential diagnosis should be considered to accurately identify the cause(s) of liver injury. Autoimmune liver diseases (autoimmune hepatitis, primary sclerosing cholangitis, overlap syndrome) can occur in the setting of limited symptoms; therefore, a high index of suspicion and appropriate diagnostic workup should be performed. Most children with autoimmune hepatitis achieve sustained remission with medical therapy; however, there are no equivalent therapies for primary sclerosing cholangitis that impact the progression of disease. Research should include biomarker studies to predict histologic remission in autoimmune hepatitis and mechanistic studies to define future treatment targets for primary sclerosing cholangitis.

We Are Not Immune: Racial and Ethnic Disparities in Autoimmune Liver Diseases

Autoimmune liver diseases are attributed to a complex interplay of biologic, acquired, and environmental factors. Increased prevalence, later stage at presentation, worse response to standard therapy, and transplant-related disparities have all been reported in racial and ethnic minorities such as Black and Latinx patients with autoimmune liver diseases. While biology and inherited genetic predispositions may partly explain these disparities, definitive and universal genetic variations underlying these differences in outcomes have not been defined. Nonetheless, socioeconomic status, access to health care, environmental and societal factors, and implicit provider bias can all contribute to poor patient outcomes. There remains an unmet need to understand and mitigate the factors contributing to health inequity in autoimmune liver diseases. In this review, we summarize the data on racial and ethnic disparities in presentation, treatment response, and outcomes pertaining to autoimmune liver diseases in minority populations, on the premise that understanding disparities is the first step toward reaching health equity.

End stage liver disease etiology & transplantation referral outcomes of major ethnic groups in British Columbia, Canada: A cohort study

Liver disease etiology and transplantation outcomes may vary by ethnicity. We aimed to determine if disparities exist in our province.We reviewed the provincial database for liver transplant referrals. We stratified cohorts by ethnicity and analyzed disease etiology and outcomes.Four thousand nine hundred sixteen referrals included 220 South Asians, 413 Asians, 235 First Nations (Indigenous), and 2725 Caucasians. Predominant etiologies by ethnicity included alcohol (27.4%) and primary sclerosing cholangitis (PSC) (8.8%) in South Asians, hepatitis B (45.5%) and malignancy (13.9%) in Asians, primary biliary cholangitis (PBC) (33.2%) and autoimmune hepatitis (AIH) (10.8%) in First Nations, and hepatitis C (35.9%) in Caucasians. First Nations had lowest rate of transplantation (30.6%, P = .01) and highest rate of waitlist death (10.6%, P = .03). Median time from referral to transplantation (268 days) did not differ between ethnicities (P = .47). Likelihood of transplantation increased with lower body mass index (BMI) (hazard ratio [HR] 0.99, P = .03), higher model for end stage liver disease (MELD) (HR 1.02, P < .01), or fulminant liver failure (HR 9.47, P < .01). Median time from referral to ineligibility status was 170 days, and shorter time was associated with increased MELD (HR 1.01, P < .01), increased age (HR 1.01, P < .01), fulminant liver failure (HR 2.56, P < .01) or South Asian ethnicity (HR 2.54, P < .01). Competing risks analysis revealed no differences in time to transplant (P = .66) or time to ineligibility (P = .91) but confirmed increased waitlist death for First Nations (P = .04).We have noted emerging trends such as alcohol related liver disease and PSC in South Asians. First Nations have increased autoimmune liver disease, lower transplantation rates and higher waitlist deaths. These data have significance for designing ethnicity specific interventions.

Paediatric autoimmune liver diseases: A descriptive study of patients from Saudi Arabia

BACKGROUND AND STUDY AIMS

Autoimmune liver diseases (ALDs) are a clinico-pathologic spectrum of disorders that share some similarities. They are formally classified as autoimmune hepatitis (AIH), isolated autoimmune sclerosing cholangitis (ASC), and the overlap syndrome of these. We describe the clinical, biochemical, and outcomes data of a cohort of autoimmune ALDs patients in a tertiary care centre.

PATIENTS AND METHODS

This is a cross-sectional study conducted at King Abdulaziz University Hospital, Jeddah, Saudi Arabia. Data were collected in 2007-2018. All cases were 18 years old or younger at the time of diagnosis. The data collection comprised clinical, laboratory, imaging, treatment, and longitudinal follow-up data.

RESULTS

Twenty-five patients were identified; 14 (56%) were females. Twenty-one patients (84%) had AIH-1,1 patient (4%) had AIH-2, and 3 patients (12%) had autoimmune sclerosing cholangitis (ASC). An insidious course was found in 21 (84%) cases. Acute hepatitis and fulminant hepatic failure was found to be very rare. Eight cases (32%) had cirrhosis at diagnosis. A total of 20 cases (80%) had complete remission following therapy. The median follow-up period was 45 months. There was no mortality, and only one patient was referred for transplant. Thus, the transplant-free survival was 96%.

CONCLUSIONS

Our study showed predominance of AIH-1 over AIH-2. Response to treatment in our cohort was found to be similar to the results found in some other key studies. Prognosis and transplant-free survival is better than many published paediatric studies.

Genetic aspects of adult and pediatric autoimmune hepatitis: A concise review

Autoimmune Hepatitis (AIH) is a heterogenous, mostly chronic liver disease that affects people of all age groups, women more often than men. The aim of therapy is to prevent cirrhosis, as it mainly accounts for liver-related mortality in patients with AIH. Rates of remission are high in patients with AIH, but life-long immunosuppressive therapy is required. AIH is hypothesized to originate from immunologic reactivity targeted against mostly unknown self-antigens, potentially triggered by viral infections among other factors. While AIH does not follow a Mendelian inheritance pattern, part of the risk of developing AIH or worse disease course, is attributed to specific genetic risk factors. Major associations for the risk of development of AIH were found for HLA-DRB1*03:01 and HLA-DRB1*04:01 in adult AIH in the only genome-wide association study on AIH. However, other potential risk loci in SH2B3, CARD10 and KIR genes were described. This review covers the current knowledge on genetic risk factors in adult and pediatric AIH.

Primary Biliary Cholangitis in British Columbia First Nations: Clinical features and discovery of novel genetic susceptibility loci

BACKGROUND & AIMS

Primary Biliary Cholangitis (PBC) is a chronic autoimmune liver disease characterized by destruction of intrahepatic bile ducts, portal inflammation and cirrhosis. Although rare in most populations, it is prevalent and often familial in British Columbia First Nations. We hypothesized that major genetic factors increased the risk in First Nations.

METHODS

In all, 44 individuals with Primary Biliary Cholangitis and 61 unaffected relatives from 32 First Nations families participated. Family history and co-morbidities were documented. Medical records were reviewed and available biopsies were re-reviewed by our team pathologist. Genotyping was performed on DNA from 36 affected persons and 27 unaffected relatives using the Affymetrix Human Mapping 500K Array Set. MERLIN software was used to carry out multipoint parametric and nonparametric linkage analysis. Candidate genes were identified and entered into InnateDB and KEGG software to identify potential pathways affecting pathogenesis.

RESULTS

In all, 34% of families were multiplex. Fifty per cent of cases and 33% of unaffected relatives reported other autoimmune disease. Three genomic regions (9q21, 17p13 and 19p13) produced LOD scores of 2.3 or greater suggestive of linkage, but no single linkage peak reached statistical significance. Candidate genes identified in the three regions suggested involvement of IL17, NFκB, IL6, JAK-STAT, IFNγ and TGFβ immune signalling pathways. Specifically, four genes-ACT1, PIN1, DNMT1 and NTN1-emerged as having roles in these pathways that may influence Primary Biliary Cholangitis pathogenesis.

CONCLUSIONS

Our whole genome linkage study results reflect the multifactorial nature of Primary Biliary Cholangitis, support previous studies suggesting signalling pathway involvement and identify new candidate genes for consideration.

Global Disparities and Their Implications in the Occurrence and Outcome of Autoimmune Hepatitis

Autoimmune hepatitis has a variable occurrence, clinical phenotype, and outcome, and the factors contributing to this variability are uncertain. The goals of this review are to examine the global disparities in the occurrence and outcome of autoimmune hepatitis, suggest bases for these disparities, and encourage investigations that extend beyond single-center experiences. Disparities in the incidence and prevalence of autoimmune hepatitis in different age groups, genders, ethnicities, and geographical regions suggest that factors other than genetic predisposition are involved. Age- and gender-related antigen exposures from the external (infections, toxins, and medications) and internal (intestinal microbiome) environment may affect the incidence of the disease, and the timeliness and nature of treatment may influence its prevalence. The increasing incidence of autoimmune hepatitis in Spain, Denmark, and the Netherlands suggests that a new etiological trigger has been introduced or that the susceptible population has changed. Variations in mortality between Western and Asian-Pacific countries may result from differences in disease detection or management, and variations in gender predilection, peak age of onset, frequency of concurrent immune diseases, and serological profile may reflect gender-biased and age-related antigen exposures and genetic predispositions. Global collaborations, population-based epidemiological studies that identify case clustering, and controlled interview-based surveys are mechanisms by which to understand these disparities and improve management. In conclusion, autoimmune hepatitis has a rising incidence in some countries and variable occurrence, phenotype, and outcome between countries and subgroups within countries. These disparities suggest that unrecognized population-based environmental, infectious, or socioeconomic factors are affecting its character.

Incidence and Characteristics of Autoimmune Hepatitis

BACKGROUND AND OBJECTIVES

Autoimmune hepatitis (AIH) is a progressive inflammatory liver disease of unknown etiology, with limited population-based estimates of pediatric incidence. We reported the incidence of pediatric AIH in Canada and described its clinical characteristics.

METHODS

We conducted a retrospective cohort study of patients aged <18 years diagnosed with AIH between 2000-2009 at all pediatric centers in Canada.

RESULTS

A total of 159 children with AIH (60.3% female, 13.2% type 2 AIH) were identified. Annual incidence was 0.23 per 100000 children. Median age at presentation for type 1 was 12 years (interquartile range: 11-14) versus 10 years for type 2 (interquartile range: 4.5-13) (P = .03). Fatigue (58%), jaundice (54%), and abdominal pain (49%) were the most common presenting symptoms. Serum albumin (33 vs 38 g/L; P = .03) and platelet count (187 000 vs 249 000; P <.001) were significantly lower and the international normalized ratio (1.4 vs 1.2; P <.001) was higher in cirrhotic versus noncirrhotic patients. Initial treatment included corticosteroids (80%), azathioprine (32%), and/or cyclosporine (13%). Response to treatment at 1 year was complete in 90%, and partial in 3%. 3% of patients had no response, and 3% responded and later relapsed. Nine patients underwent liver transplantation, and 4 patients died at a mean follow-up of 4 years.

CONCLUSIONS

AIH is uncommon in children and adolescents in Canada. Type 1 AIH was diagnosed 5.5 times more frequently than type 2 AIH. Most patients respond well to conventional therapy, diminishing the need for liver transplantation.

Autoimmune hepatitis in the Alaska Native population: autoantibody profile and HLA associations

BACKGROUND & AIMS

The Alaska Native population is one of few populations in the world with a high prevalence of autoimmune hepatitis. The objective of this study was to determine the frequency and HLA and clinical associations of autoantibodies in Alaska Native people with autoimmune hepatitis.

METHODS

Alaska Native individuals with autoimmune hepatitis were recruited in clinics conducted statewide. Sera were tested for the presence of autoantibodies described in either autoimmune hepatitis or rheumatic disease. Associations between autoantibodies and HLA alleles and clinical features were assessed.

RESULTS

Seventy-one patients were included. At the study visit, 34 patients (47.9%) had antibodies to double-stranded DNA by immunofluorescence; 27 (38.0%) had anti-neutrophil cytoplasmic antibodies; and 11 (15.5%) had anti-Ro antibodies. Only one person had antibodies against soluble liver antigen, and in that person, anti-Ro was absent. Associations were found between autoantibodies and HLA alleles, including positive associations between HLA DR3 and anti-double-stranded DNA antibodies and between HLA DR14 and antineutrophil cytoplasmic antibodies. There was no association between autoantibodies and clinical outcomes.

CONCLUSIONS

As in other populations, the prevalence of anti-double-stranded DNA antibodies and antineutrophil cytoplasmic antibodies is high in Alaska Native people with autoimmune hepatitis. In contrast to data from other populations, there is a lower prevalence of anti-soluble liver antigen and a lack of association between anti-Ro and anti-soluble liver antigen. In addition, the HLA profile and associations with autoantibodies are unique. No clear prognostic implications of autoantibodies have emerged in this population.

Primary sclerosing cholangitis, autoimmune hepatitis, and overlap in Utah children: epidemiology and natural history

The epidemiology and natural history of pediatric primary sclerosing cholangitis (PSC), autoimmune sclerosing cholangitis (ASC), and autoimmune hepatitis (AIH) are not well characterized. Using multiple, overlapping search strategies followed by a detailed records review, we identified all cases of pediatric PSC, ASC, AIH, and inflammatory bowel disease (IBD) in a geographically isolated region of the United States. We identified 607 cases of IBD, 29 cases of PSC, 12 cases of ASC, and 44 cases of AIH. The mean age at diagnosis was 13.0 years for PSC, 11.3 years for ASC, and 9.8 years for AIH. The incidence and prevalence of PSC, ASC, and AIH were 0.2 and 1.5 cases, 0.1 and 0.6 cases, and 0.4 and 3.0 cases per 100,000 children, respectively. The mean duration of follow-up was 5.9 years. The probability of developing complicated liver disease within 5 years of the diagnosis of liver disease was 37% [95% confidence interval (CI) = 21%-58%] for PSC, 25% (95% CI = 7%-70%) for ASC, and 15% (95% CI = 7%-33%) for AIH. The 5-year survival rates with the native liver were 78% (95% CI = 54%-91%) for PSC, 90% (95% CI = 47%-99%) for ASC, and 87% (95% CI = 71%-95%) for AIH. Cholangiocarcinoma developed in 2 of the 29 PSC patients (6.9%). PSC occurred in 9.9% of patients with ulcerative colitis (UC) and in 0.6% of patients with Crohn's disease (CD). ASC occurred in 2.3% of UC patients and 0.9% of CD patients. AIH occurred in 0.4% of UC patients and in 0.3% of CD patients. Liver disease occurred in 39 of 607 IBD patients (6.4%) overall.

CONCLUSION

Immune-mediated liver diseases are important sources of morbidity in children. Using a population-based design, this study quantifies the burden and natural history of immune-mediated liver disease in children.

Liver transplant outcomes in a Canadian First Nations population

BACKGROUND

A higher incidence of autoimmune disorders may predispose First Nations (FN) individuals to higher rates and more severe episodes of rejection, graft loss and mortality following liver transplantation for advanced liver disease.

METHODS

A retrospective review of patient outcomes in a single centre providing long-term follow-up care for FN and non-FN patients transplanted for advanced liver disease was conducted.

RESULTS

A total of 20 FN and 129 non-FN charts were available for review. FN subjects were younger at transplantation (mean [± SD] age 32.4±4.1 years versus 46.3±1.4 years; P=0.00005), less often male (35% versus 58%; P=0.05), more commonly transplanted for autoimmune hepatitis (30% versus 4.7%; P=0.006), less often from urban residences (25% versus 74%; P=0.0001) and less compliant with medical care (20% versus 80%; P=0.007). After a mean follow-up period of 11.0±1.5 years and 8.4±0.5 years in FN and non-FN subjects, respectively, the incidence and severity of rejection, graft and patient survival were similar between cohorts.

CONCLUSION

Although demographic profiles, nature of the underlying disease and compliance differed, the rates and severity of rejection, graft and patient survival were similar in FN and non-FN patients who underwent liver transplantation for advanced liver disease.

Non-classical phenotypes of autoimmune hepatitis and advances in diagnosis and treatment

Non-classical manifestations of autoimmune hepatitis can delay diagnosis and treatment. Our aims were to describe the clinical phenotypes that can confound the diagnosis, detail scoring systems that can ensure their recognition, and outline advances in treatment that can improve their outcome. Prime source and review articles in English were selected through Medline from 1970-2008 and assimilated into personal libraries spanning 32 years. Acute severe or asymptomatic presentations and atypical histological findings, including centrilobular zone 3 necrosis and concurrent bile duct changes, are compatible with the diagnosis. Cholangiographic abnormalities may be present in children and adults with the disease, and autoimmune hepatitis must be considered in patients without autoantibodies or with antimitochondrial antibodies and no other cholestatic features. Asymptomatic patients frequently become symptomatic; mild disease can progress; and there are no confident indices that justify withholding treatment. Two diagnostic scoring systems with complementary virtues have been developed to evaluate patients with confusing features. Normal liver tests and tissue constitute the optimal end point of treatment, and the first relapse is an indication for long-term azathioprine therapy. Cyclosporine, tacrolimus and mycophenolate mofetil are promising salvage therapies, and budesonide with azathioprine may be a superior frontline treatment. We conclude that the non-classical phenotypes of autoimmune hepatitis can be recognized promptly, diagnosed accurately, and treated effectively.

Autoimmune hepatitis in a North American Aboriginal/First Nations population

North American Aboriginal populations are at increased risk for developing immune-mediated disorders, including autoimmune hepatitis. In the present study, the demographic, clinical, biochemical, serological, radiological and histological features of autoimmune hepatitis were compared in 33 First Nations (FN) and 150 predominantly Caucasian, non-FN patients referred to an urban tertiary care centre. FN patients were more often female (91% versus 71%; P=0.04), and more likely to have low serum albumin (69% versus 36%; P=0.0006) and elevated bilirubin (57% versus 35%; P=0.01) levels on presentation compared with non-FN patients. They also had lower hemoglobin, and complement levels, more cholestasis and higher serum immunoglobulin A levels than non-FN patients (P=0.05 respectively). Higher histological grades of inflammation and stages of fibrosis, and more clinical and radiological evidence of advanced liver disease were observed in FN patients, but the differences failed to reach statistical significance. The results of the present study suggest that in addition to being more common, autoimmune hepatitis may be more severe in FN populations, compared with predominantly Caucasian, non-FN populations.

Autoimmune liver disease

PURPOSE OF REVIEW

To review studies that improve the diagnosis and treatment of autoimmune hepatitis and extend understanding of its pathogenic mechanisms.

RECENT FINDINGS

Black patients have more advanced disease and poorer outcomes than white patients. Genome-wide DNA microsatellite techniques have identified multiple regions that may confer susceptibility or resistance to the disease. Preferential inactivation of one parentally-derived X chromosome may favor autoreactivity in women. Acute and chronic hepatitis of undetermined cause can respond to corticosteroid therapy and represent autoantibody-negative autoimmune hepatitis. Outcomes can be improved by continuing therapies until resolution of all features and by early identification of problematic patients with the Model for End Stage Liver Disease. Serum levels of B-cell activating factor correlate with laboratory indices of liver injury. Tacrolimus and mycophenolate mofetil are promising therapies for problematic patients, and the antigenic targets of atypical antibodies to liver/kidney microsome may lead to diagnostic tests for de-novo autoimmune hepatitis after liver transplantation.

SUMMARY

Ethnic background and genetic predisposition affect the occurrence and outcome of autoimmune hepatitis. Susceptibility and resistance factors across the human genome underscore the genetic complexity of the disease. Outcomes can be improved by better use of current regimens and further evaluation of action-specific immunosuppressive agents.