Autoimmune liver disease

The role of the NLRP3 inflammasome and the activation of IL-1β in the pathogenesis of chronic viral hepatic inflammation

BACKGROUND AND AIMS

Chronic viral hepatitis is a prevalent disease with major health implications. Its underlying pathophysiological mechanisms are not fully understood. IL-1β and the NLRP3 inflammasome involvement has been suggested in recent years, from in vitro data and data from peripheral blood samples. Therefore, we investigated IL-1β and the NLRP3 inflammasome in liver tissues in an effort to clarify their role in the pathophysiology of chronic viral hepatitis.

METHODS

We studied liver biopsies from patients with a new diagnosis of either chronic hepatitis B (CHB) and chronic hepatitis C (CHC) or patients with chronic hepatitis B in remission (CHB-rem). The biopsies were separated in two parts. The first part was sent to histology to determine the grade of inflammation and fibrosis. From the second part, RNA was extracted and converted to cDNA used in semi-quantitative Real-Time PCR to measure the levels of IL1B, CASP1, NLRP3, ASC and IL1RA. The cell lines used in the in vitro experiments were Huh7.5, LX2 and THP-1 in variety of combinations of monocultures, co-cultures and triple cultures with one of the cell lines infected with the JFH-1 HCV clone. From the cell cultures RNA was extracted and converted to cDNA. For cell lines, we focused in the expression of IL1B and NLRP3.

RESULTS

The expression of IL1B, CASP1 and NLRP3 were found significantly different between our groups (p = 0.001, p = 0.001 and p = 0.038, respectively). CHB patients displayed significantly higher IL1B and CASP1 mRNA levels compared to both CHB-rem and CHC patients. IL1B expression significantly correlates with liver biochemical data in CHB patients (AST: p = 0.006, r = 0.457; ALT p = 0.002, r = 0.497). Finally, mRNA levels of IL1B in CHB patients significantly correlate with the degree of inflammation (p = 0.016) but not the stage of fibrosis (p = 0.362). Interestingly, the relative expression of IL1B in triple culture experiments in vitro was below of 1.5-fold, suggesting no activation of IL1B. Moreover, no activation of NLRP3 was demonstrated in all investigated in vitro conditions.

CONCLUSION

IL-1β might play an important role in the pathogenesis of chronic hepatic inflammation from HBV, but not from HCV.

Adult idiopathic cholestasis: a condition more common in the Canadian Inuit?

Despite extensive investigations, some patients have no identifiable cause for their cholestatic liver enzyme abnormalities. The aim of this study was to document the clinical, laboratory, radiologic and histologic features of adult patients with idiopathic cholestasis (AIC). A computerised database of referred patients to a tertiary care hospital outpatient department for assessment of hepatobiliary disorders between 2005 and 2015 was employed to identify and describe features associated with AIC. Of 6,560 patient referrals, sufficient documentation to warrant a diagnosis of AIC was present in 17 (0.26%) cases. Of the 17, a disproportionate number were Canadian Inuit (7/60, 12% Inuit referrals vs. 10/6,500, 0.16% non-Inuit referrals, p<0.0001). The median age of the 17 subjects was 57 years and nine (53%) were female. Clinical and/or laboratory evidence of autoimmune disorders was present in six (35%) cases. Clinical features of hepatic decompensation, radiologic findings in keeping with cirrhosis and histologic confirmation of cirrhosis were present in 47%, 31% and 42% of individuals, respectively. There were no significant improvements in cholestatic liver enzymes and function tests in those treated with ursodiol and/or immunomodulants (n=7) compared to those left untreated (n=10). In conclusion, AIC is a rare condition diagnosed by exclusion. It appears to be more common in the Canadian Inuit population and those with autoimmune disorders. Advanced liver disease is a frequent finding at presentation. Intervention with ursodiol and/or immunomodulants does not appear to be of therapeutic value.

Centrilobular necrosis in acute presentation of Japanese patients with type 1 autoimmune hepatitis

AIM

To compare clinicopathological features of acute presentation of type 1 autoimmune hepatitis (AIH) with or without centrilobular necrosis (CN).

METHODS

Our study comprised 41 patients with biopsy-proven acute presentation (acute exacerbation phase 36, acute hepatitis phase 5) of type 1 AIH at our hospital from 1975 to 2009. Elevated serum alanine aminotransferase (ALT) (> 5x upper limit of normal) identified acute presentation of the disease. We compared clinicopathological features of these AIH patients with or without CN. The data used for analysis included patient background (age, sex, type of disease, presence of complications with other autoimmune diseases, human leukocyte antigen, and International Autoimmune Hepatitis Group score), clinical parameters at presentation (ALT, alkaline phosphatase, IgG, anti-nuclear antibodies, and anti-smooth muscle antibodies), histology and therapy.

RESULTS

CN was found in 13 (31.7%) patients with acute presentation (acute exacerbation phase 10, acute hepatitis phase 3) of AIH. Serum IgG levels of patients with CN were significantly lower than those of patients without CN (mean: 2307 mg/dL vs 3126 mg/dL, P < 0.05), while antinuclear antibody-negative rates were significantly higher (30.7% vs 3.5%, P < 0.05). However, other clinical features were similar between the two groups. The frequency of advanced fibrosis in patients with CN was significantly lower than in patients without CN (F0-2: 84.6% vs 35.7%, F3-4: 15.4% vs 64.3%, P < 0.05). Other histological features were similar between the two groups. Although there was no significant difference between groups when evaluated using the revised original score (12 vs 14), the simplified AIH score of patients with CN was significantly lower (6 vs 7, P < 0.05). Frequency of DR4 was similar between patients with and without CN.

CONCLUSION

CN is observed in both Japanese patients with acute hepatitis phase and acute exacerbation phase of type 1 AIH, although AIH with CN often shows clinical features of the genuine acute form.

Mycophenolate mofetil for the treatment of autoimmune hepatitis in patients refractory or intolerant to conventional therapy

BACKGROUND

Autoimmune hepatitis is characterized by hepatocellular inflammation often progressing to cirrhosis. Standard treatment consists of corticosteroids and azathioprine. For the 20% of patients with refractory disease or those who are intolerant to medication, there is no standardized treatment.

OBJECTIVE

To evaluate mycophenolate mofetil (MMF) as an alternative therapy for autoimmune hepatitis.&nbsp;

METHODS

The present retrospective study identified all patients with autoimmune hepatitis who were treated with MMF over a 10-year period at the Henry Ford Hospital (Michigan, USA). These patients were evaluated for tolerance and response.

RESULTS

Of the 90 patients participating in the study, 48% had a complete response, 32% experienced relapses and 21% were refractory. MMF was initiated in 21 patients - 12 (57%) for refractory disease and nine (43%) for medication intolerance. Of the 12 patients converted for refractory disease, all showed biochemical improvement but none had a complete response. Of the patients converted due to intolerance, 88% maintained complete remission. For all patients converted to MMF, there was a mean decrease in steroid dose from 18.9 mg⁄day to 7.8 mg⁄day (P=0.01).

CONCLUSIONS

In patients with autoimmune hepatitis who were intolerant to conventional therapy, MMF was well tolerated, with 88% of patients maintained in remission. MMF did not induce remission in those refractory to conventional therapy; however, it resulted in a significant decrease in steroid use. Prospective studies are needed to better assess the role of MMF as an alternative therapy.

Outcomes in pediatric autoimmune hepatitis

Autoimmune hepatitis (AIH) is a common cause of acute and chronic hepatitis in childhood. Once the diagnosis is established, treatment with cortico-steroid or corticosteroid and azathioprine is indicated. Most children with AIH respond to such therapy and experience remission from active disease. Eliminating drug therapy while maintaining remission is the ultimate goal of therapy. The optimal duration of therapy before drug elimination is unclear. Relapse rate is inversely related to therapy duration before drug withdrawal; thus, discontinuing immunosuppressive treatment is considered only after at least 1 to 2 years of complete remission. When applying a slow and systematic approach, many children with AIH can successfully be weaned off immunosuppression completely. Even patients presenting in acute liver failure may avoid liver transplantation with early medical therapy. In about 10% of patients, treatment fails, requiring alternative therapies and/or liver transplantation as liver disease progresses. Less than 10% of children with autoimmune hepatitis die during 10 years of follow-up.

HLA and autoimmune digestive disease: a clinically oriented review for gastroenterologists

OBJECTIVES

The human leukocyte antigen (HLA) system includes genes involved in graft-vs-host rejection and in immune response. The discovery that HLAs are associated with several diseases led to appealing developments both in basic biomedical research and in clinical medicine, and offered the opportunity to improve the understanding of pathogenesis and classification of diseases, as well as to provide diagnostic and prognostic indicators. The aim of this article is to review the association between HLA alleles and autoimmune digestive disease and its current relationship with modern HLA nomenclature and clinical practice.

METHODS

Articles dealing with the association between HLAs and autoimmune digestive disease (including celiac disease, inflammatory bowel disease, autoimmune hepatitis, sclerosing cholangitis and primary biliary cirrhosis) were searched for using Pubmed and SCOPUS databases from earliest records to January 2008.

RESULTS

The review has provided two sections. In the first, we explain the basic principles of HLA structure, function, and nomenclature, as an introduction to the second section, which describes current associations between HLA alleles and digestive diseases. The clinical implications of each HLA association are critically discussed. Actually, a clinical role for HLA typing is suggested for only a few conditions, e.g., celiac disease.

CONCLUSIONS

The knowledge of current HLA nomenclature and of its association with some digestive diseases such as celiac disease can be useful in clinical practice for diagnostic and prognostic purposes. This can avoid improper HLA typing as well as stressing the need for further studies on other possible clinical applications.

Clinicopathological features of autoimmune hepatic diseases: an analysis of 28 cases

AIM: To investigate and compare the clinical, biological, imaging and histological features of patients with autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC) or AIH-PBC overlap syndrome (AIH-PBC OS).

METHODS: The clinical data and liver biopsy specimens from 13 patients with type I AIH, 6 patients with PBC and 9 patients with AIH-PBC OS in General Hospital of Tianjin Medical University were retrospectively analyzed.

RESULTS: Patients with AIH-PBC OS had markedly higher serum aspartate aminotransferase (AST) and γ globulin (GLO) levels than patients with AIH or PBC (132.67 ± 35.05 vs 81.15 ± 39.26, 55.17 ± 24.38; 44.33 ± 8.92 vs 34.23 ± 9.89, 33.17 ± 6.79, all P < 0.05); serum alkalinephosphatase (ALP) and gamma-glutamyl-transpeptidase (GGT) levels were significantly higher in patients with AIH-PBC OS than with AIH (218.11 ± 107.79 vs 106.85 ± 91.57; 280.33 ± 133.51 vs 82.07 ± 36.67, both P < 0.05), but lower than that in patients with PBC (245.83 ± 88.60, 315.67 ± 160.01, both P < 0.05). IgM levels in patients with PBC or AIH-PBC OS were significantly higher than in patients with AIH (793.00 ± 528.57 vs 127.33 ± 30.14; 538.50 ± 349.43vs 127.33 ± 30.14, both P < 0.05) while patients with AIH-PBC OS had significantly higher IgG levels than patients with PBC (2036.00 ± 457.03 vs 1121.25 ± 313.8, P < 0.05). Histological analysis showed interface hepatitis in 88.9% and destructive cholangitis in 66.7% of AIH-PBC OS patients. Abdominal ultrasound showed that they were all often associated with hypersplenotrophy and celiac lymphadenectasis.

CONCLUSION: AIH and PBC are representative autoimmune liver diseases in which hepatocytes and intrahepatic bile ducts, respectively, are selectively damaged by autoimmune mechanisms. AIH-PBC OS with clinicopathological features of both AIH and PBC shows closer clinically and histologically features to AIH than to PBC.

A single center review of the use of mycophenolate mofetil in the treatment of autoimmune hepatitis

BACKGROUND & AIMS

Standard treatment for autoimmune hepatitis (AIH) involves immune suppression by using prednisone alone or in combination with azathioprine (AZA). Although this regimen achieves remission in approximately 80%, some patients are intolerant or do not respond. Mycophenolate mofetil (MMF) is a potent immunosuppressant. However, its utility in AIH is not well-defined.

METHODS

We performed a retrospective longitudinal analysis of patients with AIH.

RESULTS

We identified 128 patients with AIH: mean age, 42.8 years; 83% female; 69% white. At presentation, median AST and ALT were 227 and 261 U/L, respectively, and bridging fibrosis and cirrhosis were present in 38% and 22%, respectively. Overall, 29 patients received MMF; 12 were switched to MMF after intolerance or nonresponse to prednisone +/- AZA, whereas 17 received MMF +/- prednisone as initial therapy. The main reasons for switching to MMF were nausea/vomiting (n = 4) and failure to normalize liver enzymes (n = 3). Ten of the 29 patients who received MMF therapy (34%) discontinued MMF as a result of side effects. Sixteen (84%) of the remaining 19 patients on MMF achieved remission, which closely matched the remission rate of those who remained on prednisone +/- AZA (82%). The only independent clinical factor that predicted the eventual need for the use of MMF was absence of cirrhosis (P = .0067).

CONCLUSIONS

(1) MMF was associated with a high rate of intolerance (34%). (2) In those who could tolerate it, it was associated with a high rate of remission (84%). (3) Absence of cirrhosis on presentation was the only independent factor associated with eventual need for MMF.

Hepatic centrilobular zonal necrosis with positive antinuclear antibody: a unique subtype or early disease of autoimmune hepatitis?

Centrilobular zonal necrosis (CZN) is not a pattern typically associated with autoimmune hepatitis (AIH). However, it has occasionally been reported that CZN occurs without the classic histologic features of AIH in patients with autoimmune abnormalities. In this study, we examined the clinicopathological features of 5 cases of CZN with autoimmune features not associated with classic AIH. The patients were 1 man and 4 women (24-82 years). Three patients had subjective symptoms (general malaise, arthralgia, and fever). All had antinuclear antibodies (1:40 to 1:1280). Liver biopsy showed CZN without any histologic features of classic AIH. Liver injury was sustained without medication in 4 cases, whereas it was spontaneously improved in 1 case. However, 2 months later, this patient was found to have recurrent liver dysfunction. Liver biopsy at the time of recurrence again showed CZN without the features of classic AIH. All patients were effectively treated with prednisone. Based on a review of a total of 17 cases of CZN with autoimmune features, including previously reported cases, the patients could be classified into 3 groups: cases without recurrence, cases with recurrent CZN, and cases with progression to classic AIH. Patients of the 2 former groups did not develop classic AIH during follow-up. Factors predictive of recurrence were younger age, being male, and high serum bilirubin or transaminase concentrations at first presentation (P < .05). This study suggested that CZN with autoimmune features corresponds to the early stage of classic AIH in some cases and might be a distinct type of autoimmune liver disease in others.

The revised international autoimmune hepatitis score in chronic liver diseases including autoimmune hepatitis/overlap syndromes and autoimmune hepatitis with concurrent other liver disorders

BACKGROUND

We conducted a study in order to determine the usefulness and diagnostic value of International Autoimmune Hepatitis Group (IAHG) score in non-autoimmune hepatitis (AIH) hepatic disorders as well as in AIH/overlap syndromes and in cases with coexistence of AIH and other liver diseases.

METHODS

We applied the IAHG score in 423 patients with liver diseases excluding patients with AIH, AIH/overlap syndromes and AIH with concurrent other liver disease namely, patients with chronic hepatitis B (n = 109), chronic hepatitis C (n = 95), chronic hepatitis D (n = 4), alchoholic liver disease (n = 28), non-alcoholic fatty liver disease (n = 55), autoimmune cholestatic liver diseases (n = 77), liver disorders of undefined origin (n = 32) and with miscellaneous hepatic disorders (n = 23). 24 patients with AIH associated with any kind of liver disorder including 10 patients with AIH/overlap syndromes and 14 AIH with concurrent other liver disease were also investigated. 43 patients with AIH consisted the control group.

RESULTS

The specificity of the score was 98.1% while the sensitivity in unmasking AIH in patients with either AIH/overlap syndromes or AIH with concurrent other liver diseases was only 50% and 78.6%. In the binary logistic regression model, the presence of other autoimmune diseases (p < 0.001), the total histological score (p < 0.001) and positivity for autoantibodies (p < 0.05) were identified as independent predictors for the presnce of AIH/ovea syndromes o AI with concurren other liver diseass.

CONCLUSION

The IAHG scoring system has very good specificity for excluding AIH in patients with chronic liver diseases but not that sensitivity in order to unmask AIH/overlap syndromes or AIH with concurrent other liver diseases. The presence of other autoimmune diseases or autoantibody markers in the absence of hepatitis viral markers should alarm physicians for the possible presence of AIH either as "pure" AIH or in association with other liver disorders (AIH/overlap syndromes or AIH with concurrent other liver diseases). Under these conditions, liver histology seems essential and it must always be included in the work up of hepatic patients.

Recipient and donor factors influence the incidence of graft-vs.-host disease in liver transplant patients

Acute cellular graft-vs.-host disease (GVHD) following liver transplantation has an incidence of 1 to 2% and a mortality rate of 85%. Our aim was to identify a patient population at high risk for developing GVHD using a large clinical database to study both recipient and donor factors. We compared our liver transplant patients who developed GVHD to those that did not for recipient and donor factors and combinations of factors. For 2003-2004 we had 205 first-time liver transplant patients surviving >30 days. From this group, 4 (1.9%) developed GVHD. Compared to the control group, there were no significant differences in recipient age, recipient gender, donor age, donor gender, total ischemia time, donor-recipient human leukocyte antigen (HLA) mismatch, or donor-recipient age difference. Percentages of liver disease etiologies among the patients who developed GVHD were as follows: 16% (1/6) autoimmune hepatitis (AIH) (P = 0.003), 5.6% (3/54) alcoholic liver disease (ALD) (P = 0.057), and 7.1% (3/42) hepatocellular carcinoma (HCC) (P = 0.026). The incidence of GVHD in patients with glucose intolerance (either Type I or Type II diabetes mellitus [DM]) was significant (P = 0.022). Focusing on patients only with high-risk factors for GVHD during the years 2003-2005, we had 19 such patients. Four of these high-risk patients developed GVHD. Three of these 4 patients had received a donor liver with steatosis of degree >or=mild compared to only 2 of the 15 high-risk patients who did not develop GVHD (P = 0.037). In conclusion, we have identified liver transplant patients with AIH or the combination of ALD, HCC, and glucose intolerance who receive a steatotic donor liver as being at high risk for developing GVHD.

Prospective analysis of nonadherence in autoimmune hepatitis: a common problem

OBJECTIVES

To prospectively assess nonadherence to medications, the relationship between nonadherence and medical outcome and the relationship between a psychiatric risk factor (posttraumatic stress) and nonadherence in patients with a diagnosis of autoimmune hepatitis.

PATIENTS AND METHODS

Data were obtained in children with autoimmune hepatitis, who had consented to prospective monitoring of adherence, during 1 year of follow-up in our pediatric liver program. An electronic monitoring device as well as posttransplant trough blood levels of tacrolimus was used to evaluate adherence. A validated self-report questionnaire was used to assess posttraumatic stress. The medical outcome measure was the maximal alanine transaminase (ALT) for each monitored patient.

RESULTS

Of 37 pediatric patients, 34 (15 posttransplant) enrolled. Fourteen (41%) used the monitoring device as directed. Monitor readings ranged between 28% and 94% of optimal adherence (100%). No patient took the medications exactly as prescribed. Electronic monitoring device readings correlated inversely with maximal ALT (P = 0.03, r = -0.59), and were also correlated with the tacrolimus level variability as a measure of adherence (P = 0.04, r = -0.72). Posttraumatic stress disorder questionnaire scores were correlated with both measures of adherence (for electronic monitoring, P = 0.02, r = -0.70, for tacrolimus levels, P = 0.03, r = 0.62).

CONCLUSIONS

Nonadherence to immunosuppressants was common in this cohort, and it correlated with higher maximal ALT. Nonadherence is therefore an important risk factor for poor outcome in patients with autoimmune hepatitis. Posttraumatic stress symptoms, which were correlated with nonadherence, may serve as a focus for adherence-improving interventions.