Overlap syndromes of cholestatic liver diseases and auto-immune hepatitis

Effects of adenovirus-induced hepatocyte damage on chronic bile duct inflammation in a sclerosing cholangitis mouse model

BACKGROUND & AIMS

Four major autoimmune diseases target the liver. They develop because of bile duct destruction, leading to chronic cholestasis or result from hepatocyte damage like autoimmune hepatitis (AIH). Interestingly, some patients simultaneously show features of both cholangitis and AIH. Our goal was to mimic such concurrent characteristics in a mouse model that would help deciphering mechanisms possibly involved in an inflammatory crosstalk between cholestatic disease and hepatitis.

METHODS

Mdr2^-/- mice, which spontaneously develop sclerosing cholangitis because of accumulation of toxic bile salts, were infected with adenovirus (Ad) encoding human Cytochrome P4502D6 (hCYP2D6), the major target autoantigen in type-2 AIH, to trigger hepatocyte injury. Wild type FVB mice were controls.

RESULTS

Resulting Ad-Mdr2^-/- mice presented with cholangitis, fibrosis and cellular infiltrations that were higher than in Mdr2^-/- or Ad-FVB mice. Increased levels of anti-neutrophil cytoplasmic antibodies but similar anti-hCYP2D6 antibody titres were detected in Ad-Mdr2^-/- compared to Mdr2^-/- and Ad-FVB mice respectively. IFNγ-expressing hCYP2D6-specific CD4 T cells declined, whereas hCYP2D6-specific CD8 T cells increased in Ad-Mdr2^-/- compared to Ad-FVB mice. The overall T cell balance in Ad-Mdr2^-/- mice was a combination of a type 17 T cell response typically found in Mdr2^-/- mice with a type 1 dominated T cell response characteristic for Ad-FVB mice. Simultaneously, the type 2 T cell compartment was markedly reduced.

CONCLUSIONS

Experimental hepatitis induction in a mouse with sclerosing cholangitis results in a disorder which represents not simply the sum of the individual characteristics but depicts a more complex entity which urges on further analysis.

Overlap syndromes of autoimmune hepatitis: diagnosis and treatment

Some patients with autoimmune liver disease have characteristics of cholestasis, as well as of autoimmune hepatitis. Despite the fact that this is a relatively frequent clinical condition seen in referral centers for liver diseases, there is little evidence as regards the clinical management of these syndromes due to their low prevalence and the lack of standardized definitions and diagnostic criteria. This is relevant, given that published studies report that there is a lower therapeutic response and poorer outcome in patients with overlap syndrome than in those presenting solely with autoimmune hepatitis. Whether overlap syndromes are distinct entities or the presence of 2 concurrent diseases is still a subject of debate. They should be suspected in autoimmune hepatitis patients that present with signs of cholestasis, as it is known that overlap behavior tends to be more aggressive, with higher rates of cirrhosis and the need for liver transplantation. Treatment response is also poorer and should be directed at the predominant component. Standardized definitions are necessary so that these syndromes can be studied in controlled clinical trials.

[Review of overlap syndromes in autoimmune liver diseases. Diagnostic and therapeutic difficulties]

Overlap syndromes are biochemical, serological, histological and radiological overlaps across the classic autoimmune liver diseases in the presence of autoimmun hepatitis and primary biliary cirrhosis or primary sclerosing cholangitis. The exact prevalence of the disease is not known, but it may vary between 5% and 20%. Because it has no generally accepted diagnostic criteria, clinical signs, biochemical, serological, radiological and histological findings are evaluated together. Treatment depends on the predominant feature of the overlap syndrome; ursodeoxycholic acid and/or immunsuppressive (corticosteroid) treatment are used, based on observations from retrospective, non-randomized studies.

The overlap syndromes of autoimmune hepatitis

Autoimmune hepatitis has two major variant phenotypes in which the features of classical disease are co-mingled with those of primary biliary cirrhosis or primary sclerosing cholangitis. These overlap syndromes lack codified diagnostic criteria, established pathogenic mechanisms, and confident management strategies. Their clinical importance relates mainly to the identification of patients who respond poorly to conventional corticosteroid treatment. Scoring systems that lack discriminative power have been used in their definition, and a clinical phenotype based on pre-defined laboratory and histological findings has not been promulgated. The frequency of overlap with primary biliary cirrhosis is 7-13 %, and the frequency of overlap with primary sclerosing cholangitis is 8-17 %. Patients with autoimmune hepatitis and features of cholestatic disease must be distinguished from patients with cholestatic disease and features of autoimmune hepatitis. Variants of the overlap syndromes include patients with small duct primary sclerosing cholangitis, antimitochondrial antibody-negative primary biliary cirrhosis, autoimmune sclerosing cholangitis, and immunoglobulin G4-associated disease. Conventional corticosteroid therapy alone or in conjunction with ursodeoxycholic acid (13-15 mg/kg daily) has been variably effective, and cyclosporine, mycophenolate mofetil, and budesonide have been beneficial in selected patients. The key cholestatic features that influence the prognosis of autoimmune hepatitis must be defined and incorporated into the definition of the syndrome rather than rely on designations that imply the co-mingling of different diseases with manifestations of variable clinical relevance. The overlap syndromes in autoimmune hepatitis are imprecise, heterogeneous, and unfounded, but they constitute a clinical reality that must be accepted, diagnosed, refined, treated, and studied.

Non-IBD immunological diseases are a risk factor for reduced survival in PSC

BACKGROUND

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease. It is known to be associated with immunological diseases (IDs), such as inflammatory bowel disease (IBD) and autoimmune hepatitis (AIH).

AIM

We evaluated the presence of IDs besides IBD and AIH in a cohort of PSC patients, and its association with clinical outcome.

METHODS

This is a prospective cohort study of 195 PSC patients that were evaluated over the period 1987-2010 in our tertiary care centre. The presence of ID was determined using a retrospective chart review. IDs were subclassified into autoimmune disease (AID) and immune-mediated inflammatory disease (IMID), according to current guidelines.

RESULTS

Twenty-seven of 195 (13.8%) PSC patients had at least one additional ID other than IBD (70%) or AIH (5%). The most frequent AIDs were autoimmune thyroiditis (2.6%) and diabetes mellitus type 1 (2.1%). The most frequent IMIDs were psoriasis (3.6%) and sarcoidosis (2.1%). After more than 20 years of follow-up, concomitant IDs represent an independent risk factor for reduced transplantation-free survival in patients with PSC (mean: 8.9 years vs. 16.3 years, P = 0.012). Further subgroup analysis revealed a significantly reduced survival especially in patients with concomitant IMID (P = 0.017).

CONCLUSION

Patients with concomitant IDs, especially IMID, are a clinically important subgroup of PSC patients. This significant phenotype warrants further genetic and immunological studies.

Autoimmune liver disease - are there spectra that we do not know?

Autoimmune liver diseases (AILDs) are common leading causes for liver cirrhosis and terminal stage of liver disease. They have variable prevalence among patients with liver disease and have two major clinical and biochemical presentations. Autoimmune hepatitis (AIH) is the typical example of hepatocellular AILD, but it can also be presented under a cholestatic pattern. AIH has a scoring diagnostic system and respond in most cases to the treatment with prednisolone and azathioprine. Primary biliary cirrhosis (PBC) is the second most common AILD, with a cholestatic presentation and characterized by positive antimitochondrial antibody (AMA). It has an excellent response and long term outcome with the administration of ursodeoxycholic acid (UDCA). Another AILD that is thought to be a variant of PBC is the autoimmune cholangitis, being a disease that has biochemical and histological features similar to PBC; but the AMA is negative. Primary sclerosing cholangitis (PSC) is a rare entity of AILD that has a cholestatic presentation and respond poorly to the treatment, with the ultimate progression to advance liver cirrhosis in most patients. Other forms of AILD include the overlap syndromes (OS), which are diseases with mixed immunological and histological patterns of two AILD; the most commonly recognized one is AIH-PBC overlap (AIH-PSC overlap is less common). The treatment of OS involves the trial of UDCA and different immunosuppressants. Here we present three case reports of unusual forms of chronic liver diseases that most likely represent AILD. The first two patients had a cholestatic picture, whereas the third one had a hepatocellular picture at presentation. We discussed their biochemical, immunological and histological features as well as their response to treatment and their outcomes. Then, we compared them with other forms of AILD.

Overlap syndromes: the International Autoimmune Hepatitis Group (IAIHG) position statement on a controversial issue

Some patients present with overlapping features between disorders within the spectrum of autoimmune liver diseases (i.e. autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC), and primary sclerosing cholangitis (PSC)) and are commonly classified as having an "overlap syndrome". Standardized definitions of "overlap syndromes" are lacking. The aim of this report by the International Autoimmune Hepatitis Group (IAIHG) is to evaluate if there are important reasons to classify conditions with overlapping features between autoimmune liver diseases as separate diagnostic entities. Definition of diagnostic criteria for overlap conditions can only be arbitrary. The IAIHG scoring system for diagnosis of AIH has been widely used to diagnose "overlap syndromes", but was not intended for such use and has not proven to be an efficient tool for this purpose. Some patients with overlapping features between a cholestatic and hepatitic disorder appear to benefit from treatment with a combination of ursodeoxycholic acid and immunosuppressants, but this strategy is not evidence-based, and it seems unjustified to define new diagnostic groups in this regard. The IAIHG suggests that patients with autoimmune liver disease should be categorized according to the predominating feature(s) as AIH, PBC, and PSC/small duct PSC, respectively, and that those with overlapping features are not considered as being distinct diagnostic entities. The IAIHG scoring system should not be used to establish subgroups of patients. Patients with PBC and PSC with features of AIH should be considered for immunosuppressive treatment. Due to the low prevalence of such "overlap syndromes", prospective interventional therapeutic trials cannot be expected in the foreseeable future.

Overlap syndrome of autoimmune chronic liver diseases: MRI findings

PURPOSE

To describe the MR findings of overlap syndromes of autoimmune chronic liver diseases.

METHODS

Review of clinical and radiological databases between March 2001 and July 2008 for patients with a clinical diagnosis and liver biopsy features compatible with overlap syndrome who had also undergone an abdominal MRI yielded 15 adult patients. MR features of overlap syndrome were reviewed by two radiologists by consensus. Two radiologists independently reviewed the studies in a blinded fashion for primary sclerosing cholangitis (PSC)-type or non-PSC-type features to assess interobserver agreement.

RESULTS

PSC-type and non-PSC-type overlap syndrome had distinctive MR features. In the consensus review, all 12 patients with PSC-type overlap syndrome were correctly identified. Imaging findings included central macroregeneration (N = 9), peripheral atrophy (N = 7), biliary duct beading (N = 12), biliary dilation (N = 10), or a combination of all four findings (N = 7). The presence of any of the first three features had 100% specificity for a PSC-type overlap syndrome. Patients with non-PSC-type overlap (N = 3) showed relatively normal liver morphology (N = 3) and minimal biliary ductal dilatation in one patient. There was good interobserver agreement (kappa = 0.76).

CONCLUSION

Patients with serologic or pathologic evidence of AIH or PBC with imaging features of PSC may have PSC-type overlap syndrome.

Facing the Challenge of Acute Autoimmune Liver Disease: Report of a Case and Review of the Literature

Autoimmune liver diseases (ALD) comprise two broad categories: those with a hepatic predominance, autoimmune hepatitis (AIH), and those with a predominance of cholestatic features including primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC). An overlap syndrome (OS) is thought to exist where a patient appears with clinical features of more than one immune-mediated liver disease. Based on one personal observation we report a case of histologically proven OS. The relevant literature is briefly reviewed. A 68-year-old male was admitted in our department with general malaise, anorexia and jaundice. Trans-abdominal ultrasonography as well as computerized tomography showed a slightly enlarged liver with mild fatty deposition and the patient was submitted to transcutaneous liver biopsy. Histological features included inflammatory infiltration of intra-hepatic bile ducts with the presence of endoepithelial lymphocytes and plasma cells, degenerative distortions and even focal damage of relevant epithelial cellular structures, periductal fibrosis, portal inflammation, interface hepatitis, ductular proliferation and canalicular cholestasis. It is apparent that exact definitions pertaining the OS are limited and general consensus on the precise determinations of overlap/variant syndromes is warranted in order to enable more accurate future research and establish common guidelines in the management of the condition.

Epidemiology and the initial presentation of autoimmune hepatitis in Sweden: a nationwide study

OBJECTIVE

Autoimmune hepatitis (AIH) is a chronic liver disease, which if untreated can lead to cirrhosis and hepatic failure. The aim of the study was to investigate the incidence, prevalence, diagnostic tradition and clinical initial presentation of AIH.

MATERIAL AND METHODS

Analyses were performed in 473 patients identified as having probable or definite AIH.

RESULTS

The incidence of AIH was 0.85/100,000 (95% CI 0.69-1.01) inhabitants, which is somewhat lower than reported previously. The point prevalence amounted to 10.7/100,000 (95% CI 8.8-13.1), and 76% of the cases were females. The age-related incidence curve was bimodal but men were found to have only one incidence peak in the late teens, whereas women had a peak after menopause. AIH was presented as a spectrum of clinical settings from detected "en passant" to acute liver failure. Almost 30% of patients already had liver cirrhosis at diagnosis. Autoantibodies indicative of AIH type 1 were found in 79% of cases. Other concomitant autoimmune diseases were frequently found (49%).

CONCLUSIONS

The incidence and prevalence figures confirm that AIH is a fairly uncommon disease in the Swedish population. Symptoms at presentation were unspecific, but almost half of the patients were jaundiced, with around 30% having liver cirrhosis. The majority of Swedish AIH patients had AIH type 1.

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.

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.

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.