Spectrum of liver pathology in immune mediated liver diseases

Abstract   Immune mechanisms are involved in a wide range of parenchymal liver diseases and are of particular importance in conditions where the pathogenesis appears to be related to loss of tolerance to self antigens. In the liver there are two classical 'autoimmune' conditions: primary biliary cirrhosis and autoimmune hepatitis. It is increasingly apparent however that these may represent ends of a spectrum and overlap syndromes are well recognised. Furthermore there is evidence that primary sclerosing cholangitis may be a further example of autoimmune liver disease and overlpa conditions between this and autoimmune hepatitis are described. Histopathological assessment remains an important diagnostic tool in the investigation of autoimmune liver disease, particularly in the context of outlier and overlap conditions.     

Overlap syndromes with autoimmune hepatitis in chronic cholestatic liver diseases

Conditions exhibiting features of two different autoimmune liver diseases are commonly designated overlap syndromes, although there is no current agreement on what constitutes an overlap syndrome or specific diagnostic criteria. As in the classic autoimmune liver diseases, such as autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC), the etiology is unknown but presumed to be related to alterations of immune regulation. Distinction of these clinical entities is important for management as outcomes may differ from outcomes of patients with diagnosis of classic autoimmune liver diseases. Due to their presumed rarity, no large therapeutic trials are available and treatment of overlap conditions is empirical and based upon extrapolation of data from the primary autoimmune liver diseases. PBC–AIH overlap is the most frequently described overlap syndrome and may be associated with a poor prognosis. This may represent an important and unrecognized cause of resistance to ursodeoxycholic acid in patients with PBC. PSC–AIH overlap is less commonly reported. Prognosis may be better than in patients with PSC alone; however, worse than in patients with AIH alone. Further studies are needed for determining diagnosis, natural history and optimal therapeutic strategies of overlap syndromes of autoimmune liver disease.     

2010年自身免疫性肝病临床进展回顾

本文的目的在于回顾2010年原发性硬化性胆管炎、原发性胆汁性肝硬化、自身免疫性肝炎及重叠综合征在诊断、治疗及监测等方面的研究进展     

New insights into autoimmune liver diseases.

Autoinflammatory liver disease represents an important aspect of global hepatological practice. The three principal disease divisions recognized are autoimmune hepatitis, primary sclerosing cholangitis and primary biliary cirrhosis. Largely, but not exclusively, these diseases are considered to be autoimmune in origin. Increased recognition of outlier and overlap syndromes, changes in presentation and natural history, as well as the increased awareness of IgG4-associated sclerosing cholangitis, all highlight the limitations of the classic terminology. New insights continue to improve the care given to patients, and have arisen from carefully conducted clinical studies, therapeutic trials, as well as genetic and laboratory investigations. The challenges remain to treat patients before liver injury becomes permanent and to prevent the development of organ failure.     

A case of coexisting primary biliary cirrhosis and primary sclerosing cholangitis: a new overlap of autoimmune liver diseases

Although the etiology of AIH, PBC, and PSC remains unknown, it is apparent that these autoimmune liver diseases share many common features and can coexist in the same patient. Our patient had features of PBC and later clearly developed a picture of PSC. This case suggests that PBC, PSC, AIH, and autoimmune cholangitis are part of a spectrum of chronic autoimmune liver disease that develop in response to some yet unidentified antigen.     

自身免疫性肝病诊断与治疗进展

自身免疫性肝病是一组由自身免疫介导的慢性肝胆系统损伤性疾病,主要包括自身免疫性肝炎、原发性胆汁性肝硬化及原发性硬化性胆管炎.本文就自身免疫性肝病的诊断与治疗进展进行综述.     

Celiac disease autoantibodies in severe autoimmune liver disease and the effect of liver transplantation

Background/aims: Celiac disease (CD) is associated with primary biliary cirrhosis, primary sclerosing cholangitis and autoimmune hepatitis. We investigated the following: (i) the prevalence of tissue transglutaminase antibodies (tTGAs) and endomysial antibodies (EMAs) in end‐stage autoimmune liver disease (ESALD), (ii) the correlation among auto‐antibodies and the human leucocyte antigen (HLA) haplotype, and (iii) the effect of liver transplantation on antibody kinetics. Methods: Pretransplantation sera from 488 patients (310 with ESALD, and 178 with non‐autoimmune disease) were tested for tTGAs. Positive samples were also tested for EMAs, and retested 6–12 and ≥24 months post‐transplantation. Results were correlated with the HLA type of the recipient. Results: Serological evidence of CD was found in 3% (ESALD) vs. 0.6% (non‐autoimmune) of the patients (five‐fold increased risk in ESALD). The prevalence of tTGAs (14.2 vs. 5.4%, P=0.0001) and EMAs (4.3 vs. 0.78%, P=0.01) was significantly higher in patients with the HLA‐DQ2 or HLA‐DQ8 haplotypes. tTGAs and EMAs normalized in 94 and 100%, respectively, without gluten exclusion post‐transplantation. Post‐transplantation, of the five patients with symptoms of ‘classical’ CD, three improved. Intestinal lymphoma was diagnosed in another two cases with clinically ‘silent’ CD. Conclusions: Patients with ESALD, especially those who are HLA‐DQ2 or HLA‐DQ8 positive had a high prevalence of CD‐associated antibodies. Both tTGAs and EMAs decreased post‐transplantation without gluten withdrawal. Immunosuppression may improve symptoms of CD, but might not prevent progression to intestinal lymphoma.     

Epidemiology of autoimmune liver disease

Primary biliary cirrhosis (PBC), autoimmune hepatitis (AIH) and primary sclerosing cholangitis (PSC) are chronic liver diseases that likely have an autoimmune basis to their pathogenesis. Although significant strides have been made in the clinical management of these conditions, their pathogenesis remains obscure. Understanding of various epidemiological factors may shed light on predisposing or causative factors for these diseases. Most is known about the epidemiology of PBC, with only minimal information on that of PSC and AIH. In this review, the current data on the epidemiology of PBC, AIH and PSC are summarized and suggestions are made for future work in this important area.     

Autoimmune liver diseases and diabetes: A propensity score matched analysis and a proportional meta-analysis

Background and Aims

Patients with some chronic liver diseases have increased risk of diabetes. Whether this is also the case for patients with autoimmune liver diseases is unknown. The study aimed to calculate risk and worldwide prevalence of diabetes in patients with autoimmune hepatitis (AIH), primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC).

Methods

We performed a case–control study using data from the United Kingdom Biobank (UKB) and compared frequency of type 1 diabetes (T1D) and type 2 diabetes (T2D) in AIH and PBC with age-, sex-, BMI- and ethnicity-matched controls. Next, we performed a systematic review and proportional meta-analysis searching PubMed, Embase, Cochrane Library and Web of Science (inception to 1 May 2022 [AIH]; 20 August 2022 [PBC]; 11 November 2022 [PSC]). The pooled prevalence of diabetes was calculated using an inverse method random effects model.

Results

Three hundred twenty-eight AIH patients and 345 PBC patients were identified in UKB and risk of T1D and T2D significantly increased compared with matched controls. Our systematic search identified 6914 records including the UKB study. Of these, 77 studies were eligible for inclusion comprising 36 467, 39 924 and 4877 individuals with AIH, PBC and PSC, respectively. The pooled prevalence of T1D was 3.8% (2.6%–5.7%), 1.7% (0.9%–3.1%), 3.1% (1.9%–4.8%) and of T2D 14.8% (11.1%–19.5%), 18.1% (14.6%–22.2%), 6.3% (2.8%–13.3%) in patients with AIH, PBC and PSC, respectively.

Conclusions

Patients with autoimmune liver diseases have increased risk of diabetes. Increased awareness of diabetes risk in patients with autoimmune liver diseases is warranted.     

A scoring system for primary biliary cirrhosis and its application for variant forms of autoimmune liver disease

Background: Although primary biliary cirrhosis (PBC) and autoimmune hepatitis (AIH) are two independent autoimmune liver diseases, it is sometimes difficult to characterize the variant forms of autoimmune liver disease. A PBC scoring system, in combination with the AIH scoring system may be helpful to characterize such patients. Methods: A PBC scoring system was introduced that selected 14 categories characteristic of PBC. One hundred and thirty-four patients with PBC, 31 patients with autoimmune cholangitis (AIC), 22 patients with overlap syndrome, and 48 patients with AIH were included in the study. The AIC patients fulfilled the PBC criteria but were negative for anti-mitochondrial antibody and positive for anti-nuclear antibody. Overlap syndrome patients fulfilled both the PBC and AIH criteria. Results: The total scores (means ± SD) for the PBC, AIC, overlap syndrome, and AIH patients were 23.3 ± 4.7, 9.3 ± 4.4, 18.0 ± 5.9, and 3.6 ± 3.3, respectively. When definite and probable PBC patients were defined as those with a total score of over 17 and 9–17, respectively, all except for 1 patient could be classified as definite or probable PBC. Four of the 48 AIH patients were classified as probable PBC. PBC scores for the variant autoimmune liver diseases showed a wide deviation. Plotting both PBC and AIH scores in a rectangular coordinate enabled us to locate each patient with variant forms according to the deviation from classical PBC or AIH. Conclusions: The PBC scoring system might be useful in characterizing the features of variant forms of autoimmune liver disease. Received: March 6, 2002 / Accepted: June 14, 2002 Reprint requests to: K. Yamamoto Editorial on page 106     

Overlap syndromes from pediatrics to adulthood

Abstract   Overlap syndromes are autoimmune conditions with mixed immunological, clinical and histological features. The most frequent overlaps are between primary biliary cirrhosis (PBC) and autoimmune hepatitis (AIH), and between AIH and sclerosing cholangitis (SC). True AIH/PBC overlap syndrome is rare and characterized by elevation of transaminases and immunoglobulin G (IgG), positive anti-smooth muscle antibodies and a liver biopsy showing interface hepatitis as well as changes typical of PBC. These patients respond to immunosuppressive treatment that must be given promptly, to avoid progression to liver failure. The so-called 'autoimmune cholangitis' defines a small group of patients with cholestatic and histological features of PBC but negative for anti-mitochondrial antibody (AMA) and positive for PBC-specific anti-nuclear antibody (ANA). The positivity for ANA in these patients is a consequence of the AMA negativity, since AMA masks ANA on immunofluorescence. These patients' clinical course and response to treatment resemble that of classical PBC. AIH/ASC overlap syndrome is characterised by elevated levels of IgG and circulating autoantibodies, including ANA, SMA and atypical perinuclear anti-neutrophil cytoplasmic antibody, in association with cholangiographic changes typical of SC. This condition affects in particular children and young adults and may represent the early stage of adult primary SC. The parenchymal liver inflammation responds satisfactorily to immunosuppression, while the bile duct damage may progress despite treatment.     

Occult hepatitis B virus infection in patients with autoimmune liver diseases

Background: Occult hepatitis B virus (HBV) infection is characterized by undetectable serum HBV surface antigen (HBsAg) but detectable HBV‐DNA in serum or liver. Aims: To determine the prevalence and clinical impact of occult HBV in autoimmune liver diseases as similar data are missing. Methods: One hundred and ninety‐six sera samples from HBsAg‐negative patients, including 66 autoimmune hepatitis (AIH), 93 primary biliary cirrhosis (PBC) and 37 primary sclerosing cholangitis (PSC), were investigated for HBV‐DNA using the polymerase chain reaction (PCR) before treatment initiation. One hundred and three serial samples from 38 AIH patients under immunosuppression and 282 selected blood donors (HBsAg negative; antibodies to HBV‐core antigen positive) were also investigated. Fourteen available paraffin‐embedded AIH liver samples were also investigated for HBV‐DNA by nested‐PCR. Results: Hepatitis B virus DNA was detected in the serum of 24/196 patients (12.2%) and 0/282 donors (P=0.0000). Nine patients had AIH (13.6%), eight had PBC (8.6%) and seven had PSC (18.9%) (P=0.0000 vs healthy). HBV‐DNA detection in AIH livers was higher than in serum. HBV‐DNA was associated neither with HBV markers nor with epidemiological, laboratory and clinical data. Serial testing of AIH patients revealed two HBV‐DNA‐negative patients before treatment becoming positive during treatment, while all HBV‐DNA‐positive patients before immunosuppression became negative. Conclusion: Based mainly on serum HBV‐DNA, we found a significant proportion of autoimmune liver disease patients with occult HBV compared with donors. However, taking into account our results in a small number of liver tissues, it should be emphasized that occult HBV could be even higher when both serum and liver specimens are investigated. Occult HBV does not seem to affect the clinical and laboratory features of the diseases, while AIH patients with occult HBV under immunosuppression do not deteriorate during follow‐up.     

The future of autoimmune liver diseases – Understanding pathogenesis and improving morbidity and mortality

Autoimmune liver diseases (AILD), namely autoimmune hepatitis (AIH), primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC), are rare diseases. These days, patients with PBC almost never require liver transplantation. When treated early with ursodeoxycholic acid patients have a normal life expectancy if the disease is diagnosed at an early stage and the patients respond to treatment. Patients with AIH often go into remission with first‐line therapy including corticosteroids alone or in combination with azathioprine. Nevertheless, about one quarter of patients already developed cirrhosis at diagnosis. Those who do not respond to first line standard of care (SOC) have significant liver‐related morbidity and mortality. No approved second‐ or third‐line treatments are available and the drugs are selected based on limited case series and personal experience. Larger trials are needed to develop efficient therapies for difficult‐to‐treat AIH patients. No treatment has been found to alter the natural course of disease in patients with PSC except for liver transplantation. Identifying PSC patients at risk of developing cholangiocarcinoma (CCA) is another unmet need. Current research in all AILD including AIH, PBC and PSC, focuses on improving our understanding of the underlying disease process and identifying new therapeutic targets to decrease morbidity and mortality.     

Pathology of autoimmune liver diseases in children

Liver disorders are more diverse in children than in adults, and autoimmune liver diseases also develop in childhood, although rarely. The autoimmune diseases in children comprise autoimmune hepatitis (AIH) and primary sclerosing cholangitis (PSC). The pathology of AIH and PSC is described. Although AIH in children is rare, it occurs in early childhood, and some elementary school students have been reported to develop cirrhosis. The histology of AIH in children is essentially the same as that in adults. We analyzed eight patients with childhood AIH. Four of these patients had a high AIH score, with typical histological features of AIH, that is, interface hepatitis with infiltration of lymphocytes and plasma cells, a severe necroinflammatory reaction and rosette formation of hepatocytes. Multinucleated hepatocytes were observed in three patients. This finding seems characteristic of childhood AIH, although rarely observed in adult AIH. Clinically, the distinction between AIH and PSC is often difficult in childhood, and the overlapping of both has also been reported. PSC-like histological features may be observed in some pediatric patients with AIH. In patients with acute onset of AIH, they show a pronounced necroinflammatory reaction in zone 3 (central area). Because an autoimmune phenomenon may occur in the early stage of childhood PSC, it is difficult to differentiate it from AIH in some patients. Some patients are diagnosed with AIH in the early stage, but with PSC during long-term follow up. The histopathological findings of childhood PSC are the same as those of adult PSC, and are characterized by biliary-type portal fibrosis and onion-like periductal fibrosis in medium-sized portal tracts.     

不同类型自身免疫性肝病患者肝组织炎症因子表达的变化

目的 探讨不同类型自身免疫性肝病(AILD)患者肝组织炎症因子表达的变化。方法 2016年12月～2018年12月我院肝病科收治的AILD患者74例,其中自身免疫性肝炎(AIH)患者19例,原发性胆汁性肝硬化(PBC)患者42例,自身免疫性肝炎/原发性胆汁性肝硬化重叠综合症(AIH/PBC OS)患者13例。采用免疫组化法检测肝穿组织白介素-12(IL-12)、IL-17和干扰素-γ(IFN-γ)表达情况。结果 AIH、PBC和AIH-PBC OS患者血清ALT水平分别为(132.5±12.5)U/L、(40.1±8.4)U/L和(166.2±16.3)U/L,AST水平分别为(120.3±11.7)U/L、(52.8±5.6)U/L和(194.7±18.3)U/L,差异显著(P<0.05);血清ALP水平分别为(98.0±9.2)U/L、(323.5±30.9)U/L和(257.1±24.1)U/L,血清GGT水平分别为(49.1±4.7)U/L、(236.8±22.6)U/L和(376.7±35.5)U/L,差异显著(P<0.05);AIH、PBC和AIH-PBC OS组患者肝组织IL-12表达阳性率无统计学差异(分别为15.8%、7.1%和15.4%,P>0.05),肝组织IL-17阳性表达率无统计学差异(分别为73.7%、76.2%和76.9%,P<0.05),肝组织IFN-γ阳性表达率无统计学差异(分别为68.4%、85.7%和76.9%,P<0.05);AIH患者血清抗肝肾微粒体I型抗体(LKM-1)、抗可溶性肝抗原/肝胰抗原抗体(SLA/LP)阳性率分别为21.1%和10.8%,均显著高于PBC组或AIH-PBC OS患者(分别为0.0%和0.0%,和0.0%和0.0%,P<0.05);PBC患者血清抗sp100抗体阳性率为19.0%,显著高于AIH组(0.0%)或AIH-PBC OS患者(7.7%,P<0.05);AIH-PBC OS组血清抗gp210抗体阳性率为38.5%,显著高于AIH组(0.0%,P<0.05),AIH-PBC OS组患者血清抗线粒体M2抗体(AMA-M2)阳性率为100.0%,显著高于AIH组(0.0%)或PBC组(73.8%,P<0.05);AIH患者血清ANA和SMA阳性率分别为94.7%和78.9%,显著高于PBC患者(分别为19.0%和19.0%,P<0.05)。结论 不同类型AILD患者血清自身抗体呈交叉阳性现象,肝组织炎性因子检测对鉴别诊断没有意义,常规肝功能指标仍对诊断起关键作用。     

自身免疫性肝病的病理学新进展

自身免疫性肝病是指由于机体免疫系统攻击自体肝组织引起的肝组织损伤和肝功能异常的一组免疫性疾病,包括有自身免疫性肝炎(AIH)、原发性胆汁性肝硬化(PBC)和原发性硬化性胆管炎(PSC).通常情况下这三种肝脏疾病独立存在,约有6％～9％的患者可以在同一时段或病程中出现两种疾病的临床表现、血清学和组织学特征,称为重叠综合征.近年来随着对自身免疫性肝病认识水平的提高以及自身抗体检测方法的不断改进,一些学者在自身免疫性肝病的经典肝组织学病变特点的基础上,提出了一些见解,介绍如下.     

Recurrence of autoimmune liver diseases after liver transplantation

Liver transplantation(LT) is the most effective treatment modality for end stage liver disease caused by many etiologies including autoimmune processes. That said, the need for transplantation for autoimmune hepatitis(AIH) and primary biliary cirrhosis(PBC), but not for primary sclerosing cholangitis(PSC), has decreased over the years due to the availability of effective medical treatment. Autoimmune liver diseases have superior transplant outcomes than those of other etiologies. While AIH and PBC can recur after LT, recurrence is of limited clinical significance in most, but not all cases. Recurrent PSC, however, often progresses over years to a stage requiring re-transplantation. The exact incidence and the predisposing factors of disease recurrence remain debated. Better understanding of the pathogenesis and the risk factors of recurrent autoimmune liver diseases is required to develop preventive measures. In this review, we discuss the current knowledge of incidence, diagnosis, risk factors, clinical course, and treatment of recurrent autoimmune liver disease(AIH, PBC, PSC) following LT.     

The management of autoimmunity in patients with cholestatic liver diseases

Cholestatic liver diseases are rare diseases that often lead to cirrhosis and its consequent complications. In addition to liver-related morbidity, patients with cholestatic liver diseases often suffer from autoimmune diseases that affect several organs and tissues. The robust and efficient data collection and collaboration between hepatologists and rheumatologists have led to significant advancements in understanding the relationship between the cholestatic liver diseases and associated autoimmune diseases. In this paper, we discuss the cholestatic liver diseases (primary biliary cirrhosis, primary sclerosing cholangitis and immunoglobulin G4 associated cholangitis) and associated autoimmune diseases.