Prevalence of autoimmune liver disease in Alaska Natives

The challenges in primary sclerosing cholangitis--aetiopathogenesis, autoimmunity, management and malignancy

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease, characterized by progressive inflammation and fibrosis of the bile ducts, resulting in biliary cirrhosis and is associated with a high risk of cholangiocarcinoma. The majority of patients are young, male and have coexisting inflammatory bowel disease. PSC is found with a prevalence of 10/100,000 in Northern European populations. The pathophysiology of PSC is a complex multistep process including immunological mechanisms, immunogenetic susceptibility and disorders of the biliary epithelia. The diagnosis is primarily based on endoscopic cholangiography although magnetic resonance imaging is increasingly used; biochemistry and immunoserology as well as histology play only a minor role. Due to the high risk of developing cholangiocarcinoma and also other tumours of the GI tract, surveillance strategies are essential, however they have yet to be established and evaluated. Biochemical parameters, clinical risk factors, endoscopic procedures and imaging techniques contribute to the early identification of patients at risk. Since medical therapy of PSC with ursodeoxycholic acid does not improve survival, to date, liver transplantation is the only option with a cure potential; if transplantation is accurately timed, transplanted PSC patients have an excellent rate of survival. However if cholangiocarcinoma is detected, a curative treatment is not possible in the majority of cases. The present review critically summarizes the current knowledge on the aetiopathogenesis of PSC and gives an overview of the diagnostic approaches, surveillance strategies and therapeutic options. Primary sclerosing cholangitis is a disease of unknown aetiology and without any further curative treatment options apart from liver transplantation. Therefore it may be regarded as the greatest challenge in hepatology today.

Clinical features and management of primary biliary cirrhosis

Primary biliary cirrhosis (PBC), which is characterized by progressive destruction of intrahepatic bile ducts, is not a rare disease since both prevalence and incidence are increasing during the last years mainly due to the improvement of case finding strategies. The prognosis of the disease has improved due to both the recognition of earlier and indolent cases, and to the wide use of ursodeoxycholic acid (UDCA). New indicators of prognosis are available that will be useful especially for the growing number of patients with less severe disease. Most patients are asymptomatic at presentation. Pruritus may represent the most distressing symptom and, when UDCA is ineffective, cholestyramine represents the mainstay of treatment. Complications of long-standing cholestasis may be clinically relevant only in very advanced stages. Available data on the effects of UDCA on clinically relevant end points clearly indicate that the drug is able to slow but not to halt the progression of the disease while, in advanced stages, the only therapeutic option remains liver transplantation.

Current diagnosis and management of primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is an important liver disease with major morbidity and mortality. The diagnosis of PSC is confirmed by magnetic resonance cholangiopancreaticography, and endoscopic retrograde cholangiopancreaticography is performed in patients needing therapeutic endoscopy. As a result of the unknown cause of the disease, current medical therapies are unsatisfactory. Nevertheless, high-dose ursodeoxycholic acid should be recommended for treatment of PSC patients because there is a trend toward increased survival. Dominant bile duct stenoses should be treated endoscopically. However, liver transplantation continues to be the only therapeutic option for patients with advanced disease. Estimation of prognosis and timing of liver transplantation should be determined individually for each PSC patient on the basis of all results. The diagnosis and treatment of cholangiocarcinoma (CC) still remain a challenge in PSC patients. Early diagnosis of CC certainly is a prerequisite for successful treatment with surgical resection or innovative strategies such as neoadjuvant radiochemotherapy with subsequent orthotopic liver transplantation. Therefore, endoscopic techniques such as cholangioscopy and/or intraductal ultrasound may be useful diagnostic tools in patients with stenoses suspicious for malignancy.

Recent advances in the epidemiology of primary biliary cirrhosis

Since initial reports in the mid-1970s provided epidemiology data on primary biliary cirrhosis (PBC), many studies have characterized the variable frequency of this disease in diverse populations worldwide and sought to identify associated risk factors. Recent research confirms earlier work suggesting that the incidence and prevalence of PBC are on the rise, although geographic variation persists. Analysis of familial and geographic clustering supports the hypothesis that development and progression of the disease hinge on a complex interplay between genetic and environmental risk factors. International clinical data systems are needed to advance PBC epidemiologic research. Given this complexity, international clinical data systems are needed to advance PBC epidemiologic research.

Genetic factors affecting the occurrence, clinical phenotype, and outcome of autoimmune hepatitis

Autoimmune hepatitis is a polygenic disorder of unknown cause in which the genetic risk factors that affect occurrence, clinical phenotype, severity, and outcome still are being clarified. The susceptibility alleles in white North American and northern European patients reside on the DRB1 gene, and they are DRB1*0301 and DRB1*0401. These alleles encode a 6 amino acid sequence at positions 67-72 in the DRbeta polypeptide chain of the class II molecules of the major histocompatibility complex. This sequence is associated with susceptibility, and lysine at position DRbeta71 is the key determinant. Molecular mimicry between foreign and self-antigens may explain the loss of self-tolerance and the occurrence of concurrent immune diseases in anatomically distant organs. Disease severity is associated with the number of alleles encoding lysine at DRbeta71 (gene dose) and the number of polymorphisms, including those of the tumor necrosis factor-alpha gene, cytotoxic T lymphocyte antigen-4 gene, and tumor necrosis factor-receptor superfamily gene, that can modify the immune response. Individuals in different geographic regions may have different susceptibility alleles that reflect indigenous triggering antigens, and these may provide clues to the etiologic agent. Knowledge of the genetic predispositions for autoimmune hepatitis may elucidate pathogenic mechanisms, identify etiologic agents, characterize susceptible populations, foresee outcomes, and target new therapies. These lessons may be applicable to autoimmune disease in general.

Primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is a chronic and slowly progressive cholestatic liver disease of autoimmune etiology characterized by injury of the intrahepatic bile ducts that may eventually lead to liver failure. Affected individuals are usually in their fifth to seventh decades of life at time of diagnosis, and 90% are women. Annual incidence is estimated between 0.7 and 49 cases per million-population and prevalence between 6.7 and 940 cases per million-population (depending on age and sex). The majority of patients are asymptomatic at diagnosis, however, some patients present with symptoms of fatigue and/or pruritus. Patients may even present with ascites, hepatic encephalopathy and/or esophageal variceal hemorrhage. PBC is associated with other autoimmune diseases such as Sjogren's syndrome, scleroderma, Raynaud's phenomenon and CREST syndrome and is regarded as an organ specific autoimmune disease. Genetic susceptibility as a predisposing factor for PBC has been suggested. Environmental factors may have potential causative role (infection, chemicals, smoking). Diagnosis is based on a combination of clinical features, abnormal liver biochemical pattern in a cholestatic picture persisting for more than six months and presence of detectable antimitochondrial antibodies (AMA) in serum. All AMA negative patients with cholestatic liver disease should be carefully evaluated with cholangiography and liver biopsy. Ursodeoxycholic acid (UDCA) is the only currently known medication that can slow the disease progression. Patients, particularly those who start UDCA treatment at early-stage disease and who respond in terms of improvement of the liver biochemistry, have a good prognosis. Liver transplantation is usually an option for patients with liver failure and the outcome is 70% survival at 7 years. Recently, animal models have been discovered that may provide a new insight into the pathogenesis of this disease and facilitate appreciation for novel treatment in PBC.

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

BACKGROUND

It has been previously reported that British Columbia's (BC's) First Nations (Aboriginal) community has an increased risk of autoimmune diseases, including rheumatological conditions (rheumatoid arthritis, systemic lupus) and primary biliary cirrhosis. The researchers hypothesized that this community may also be at increased risk for autoimmune hepatitis (AIH).

METHODS

Independent, retrospective reviews of the databases of two separate tertiary/quaternary British Columbia university-affiliated health care institutions, the Adult Liver Transplant Program of the BC Transplant Society and the Division of Pediatric Gastroenterology, BC Children's Hospital (Vancouver, BC), were performed. All patients referred with a diagnosis of probable or definite AIH who identified themselves as being of First Nations descent from 1988 to 2004 were reviewed. The liver transplant database records all adult patients in the province referred for transplant assessment. The pediatric database records all children referred to the BC Children's Hospital.

RESULTS

A total of 68 adult patients with a definite or probable diagnosis of AIH were referred to the liver transplant program. Twelve patients (17.6%) were Aboriginal, 11 of which were female. Similarly, a total of 30 children with probable or definite AIH were identified from the pediatric database. Six of these cases (20%) were identified in Aboriginal children.

CONCLUSIONS

The findings suggest an increased prevalence of AIH among BC's First Nations community. A disproportionate First Nations representation was found on independent review of two databases. Future studies are needed to determine the true prevalence of AIH in this community, and to uncover the genetic predisposition and the environmental triggers explaining this phenomenon.

Autoimmune hepatitis. Part B: diagnosis

Diagnostic criteria have been codified by the International Autoimmune Hepatitis Group, and a scoring system can quantify the strength of the diagnosis and over-ride the impact of absent or inconsistent features. The absence of a definable etiologic agent and precise diagnostic test, implies that the diagnosis may be missed or misapplied. Centrilobular (zone 3) necrosis may be an early form of autoimmune hepatitis and this pattern can transform to the classical pattern of interface hepatitis. An acute severe or fulminant presentation is possible, and different ethnic groups may have different manifestations and outcomes. Asymptomatic patients at presentation commonly become symptomatic, and treatment decisions must be based on objective features of disease severity and not the presence or absence of symptoms. Concurrent autoimmune diseases are frequent, and they may constitute an autoimmune polyglandular syndrome associated with a single gene mutation. Emerging autoantibodies of possible prognostic value are antibodies to soluble liver antigen/liver pancreas, asialoglycoprotein receptor, actin, and liver cytosol type 1. HLA DRB1*03, *04, *03-*04, *07, *13 and DQB1*02 are associated with the occurrence, clinical phenotype and outcome of autoimmune hepatitis. Variant syndromes should be suspected if cholestatic features are prominent and conventional treatment is ineffective.

Prevalence and predictors of esophageal varices in patients with primary biliary cirrhosis

BACKGROUND & AIMS

Esophageal varices and bleeding are among the most feared complications of primary biliary cirrhosis (PBC). We aimed to determine the prevalence of esophageal varices in patients with PBC, to evaluate noninvasive markers of esophageal varices in this population, and to validate the results in an independent set of patients.

METHODS

Data were collected on all patients with PBC seen for the first time at the University of Florida (study group) and at Case Western Reserve University hospitals (cross-validation group) during 7 consecutive years. Logistic regression analysis was used to identify independent predictors of esophageal varices. The best cut-off values were calculated based on receiver operating characteristic curves. The diagnostic accuracy of the independent predictors of esophageal varices identified in the study group were retested in the cross-validation group.

RESULTS

Of 210 patients with PBC seen at the University of Florida, 113 had an endoscopy and 49.6% (56 of 113) were found to have esophageal varices. After excluding 22 patients with a history of variceal bleeding, data on 91 patients were analyzed. Thirty-four patients had esophageal varices (37%). Multivariate analysis revealed that a platelet count of less than 140,000 (odds ratio, 7.6; 95% confidence interval, 1.6-37) and a Mayo risk score of 4.5 or greater (odds ratio, 10.6; 95% confidence interval, 1.8-62) were independent predictors of esophageal varices. The diagnostic accuracy of these predictors was confirmed in an independent set of patients.

CONCLUSIONS

Among patients with PBC, a platelet count of less than 140,000 and/or a Mayo risk score of 4.5 or greater appears to identify those patients more likely to benefit from a screening endoscopy.

Clinical epidemiology of primary biliary cirrhosis: incidence, prevalence, and impact of therapy

Primary biliary cirrhosis (PBC) is a chronic cholestatic liver disease of unknown etiology. It is typically characterized by a trio of criteria including cholestatic liver biochemistry tests for at least 6 month's duration, the presence of a positive serum antimitochondrial antibody, and histologic findings from liver biopsy that are compatible or diagnostic with PBC. Although no unifying mechanism of action has been described to explain the pathogenesis of PBC to date, the natural history of this condition is greatly influenced by several known and unknown risk factors. In turn, a number of publications have focused on describing the burden of disease and prognosis in patients with PBC, This review article will summarize the descriptive epidemiology of PBC including new insights on risk factors, prognosis, and the effect of medical therapy in contemporary patients.

Overlap syndrome of primary biliary cirrhosis and autoimmune hepatitis: a retrospective study of 115 cases of autoimmune liver disease

OBJECTIVE

The aim of this retrospective study was to compare clinical, biological, and histological features and treatment response in 115 patients with overlap syndrome (OS), autoimmune hepatitis (AIH) or primary biliary cirrhosis (PBC).

METHODS

Consecutive patients with AIH, PBC or OS followed between 1984 and 2005 in five different centers were included. All data were re-evaluated using current diagnostic criteria of each disease.

RESULTS

Fifteen patients had OS (13 females), 48 AIH (40 females) and 52 PBC (49 females). Patients with OS were significantly younger than patients with PBC (median age: 44 vs 59 years). Jaundice (20%) and pruritus (20%) were the main initial symptoms in OS. Patients with OS had serum transaminase and gammaglobulin levels significantly higher than patients with PBC; serum alkaline phosphatase, gamma-glutamyl-transpeptidase and IgM levels were significantly higher in OS than in patients with AIH. Histological analysis showed moderate or severe piecemeal necrosis in 86% and destructive cholangitis in 93% in OS group. Among 11 patients with OS treated with ursodeoxycholic acid (UDCA) or immunosuppressors alone, only 6 had a complete biochemical response. In contrast, all patients with OS receiving combined therapy, as first or second line, responded, 5 patients to the combination corticosteroids-azathioprine-UDCA and 2 to the combination cyclosporine-UDCA.

CONCLUSION

OS is not rare and accounts for 13.9% of patients with autoimmune liver disease in our series. Combination of immunosuppressors and UDCA appears the most efficient treatment in these patients.

Primary sclerosing cholangitis: summary of a workshop

Primary sclerosing cholangitis (PSC) is a rare but important liver disease that leads to cirrhosis and need for liver transplantation in a high proportion of cases. The disease occurs in approximately 1 per 100,000 population per year, usually presents in adulthood, and affects men more often than women. Typical serum biochemical results, autoantibodies and liver biopsy are suggestive but not diagnostic of PSC, the diagnosis requiring cholangiographic demonstration of stricturing and dilatation of the intra- and/or extra-hepatic bile ducts. The natural history of PSC is variable, the average survival being 12 to 17 years. The cause of PSC is still unknown. Although considered an autoimmune disease, PSC has several atypical features and a strong genetic component. The therapy of PSC is unsatisfactory. Standard doses of ursodeoxycholic acid (UDCA) lead to improvements in biochemical abnormalities but not in histology, cholangiographic appearance or survival. Several innovative therapies have been tried in PSC, but with scant evidence of benefit. For patients with high grade strictures, endoscopic dilatation is beneficial. Liver transplantation is successful for end-stage liver disease due to PSC and improves survival. PSC may recur after transplantation but is rarely progressive. The most dreaded complication of PSC is cholangiocarcinoma. Diagnosis of this highly malignant tumor is difficult, and there are no biomarkers for its early detection. Liver transplantation for cholangiocarcinoma has an exceedingly poor outcome, although transplantation with neoadjuvant chemoirradiation holds promise in selected patients. Thus, significant opportunities remain for basic and clinical research into the cause, natural history, and therapy of PSC.

Autoimmune liver disease and the Canadian First Nations Aboriginal Communities of British Columbia’s Pacific Northwest

Primary biliary cirrhosis (PBC) is a well-known but uncommon chronic liver disease that is presumed to be of autoimmune etiology. Recently, investigations in British Columbia (BC), a province of Canada situated along the Pacific North-West of North America, have suggested that PBC is not a rare disease amongst BC’s Aboriginal (i.e. First Nations) communities. Geographically, BC is adjacent to South East Alaska, an American state that has also reported an increased prevalence of PBC amongst its Aboriginal communities. In this article, the medical evidence supporting a hypothesis of increased risk of PBC amongst BC’s First Nations communities is reviewed. Evidence suggesting that autoimmune hepatitis is also more likely amongst BC’s First Nations communities is also presented.

Autoimmune hepatitis, from mechanisms to therapy

In 1950, Waldenström was the first to describe a chronic form of hepatitis in young women. Subsequently, the disease was found to be associated with other autoimmune syndromes and was later termed "lupoid hepatitis" because of the presence of antinuclear antibodies. In 1965, it became designated by Mackay et al. as "autoimmune hepatitis" at an international meeting, at which the general concept of autoimmunity was endorsed by the scientific community. In the early 1960s and 1970s, the value of immunosuppressive therapy with glucocorticoids and/or azathioprine was well documented in several studies. The original association of autoimmune hepatitis (AIH) and HLA alleles, which has remarkably stood the test of time, was published in 1972. In the 1970s and 1980s, several autoantibodies were identified in patients with autoimmune hepatitis directed against proteins of the endoplasmatic reticulum expressed in liver and kidney and against soluble liver antigens. Subsequently, the molecular targets of these antibodies were identified and more precisely characterized. In the last two decades many additional pieces of the AIH puzzle have been collected leading to the identification of additional antibodies and genes associated with AIH and to the emergence of new therapeutic agents. Meanwhile, the immunoserological and genetic heterogeneity of AIH is well established and it has become obvious that clinical manifestations, disease behavior, and treatment outcome may vary by racial groups, geographical regions and genetic predisposition. Currently, the International Autoimmune hepatitis group is endorsing multi-center collaborative studies to more precisely define the features at disease presentation and to define prognostic indices and appropriate treatment algorithms. Given the importance of serological testing, the IAHG is also working on guidelines and procedures for more reliable and standardized testing of autoantibodies.

Treatment challenges and investigational opportunities in autoimmune hepatitis

New drugs and advances in molecular biology afford opportunities to upgrade the treatment of autoimmune hepatitis. The aims of this study were to define treatment problems, identify possible solutions, and stimulate investigations to improve patient care. A clinical subcommittee of the International Autoimmune Hepatitis Group reviewed current management difficulties and proposed corrective actions. The assessment of new front-line and salvage therapies for adults and children were given top priority. Cyclosporine and mycophenolate mofetil were endorsed as drugs worthy of rigorous study in severe disease, and budesonide was endorsed for study as front-line therapy in mild disease. Diagnostic criteria and treatment regimens for children required codification, and pharmacokinetic studies were encouraged to develop optimal dosing schedules based on therapeutic ranges. Collaborative efforts were proposed to help understand racial, geographical, and genetic factors affecting outcome and to establish definitions and therapies for variant syndromes and graft dysfunction after transplantation. The development of experimental animal models was deemed essential for the study of site-specific molecular interventions, and gene therapy was endorsed as a means of bolstering reparative processes. In conclusion, evolving pharmacological and technical advances promise to improve the treatment of autoimmune hepatitis, and investigations of these advances are timely, feasible, and necessary.

[Incidence and prevalence of autoimmune hepatitis in the area of the Hospital de Sagunto (Spain)]

Thirteen cases of autoimmune hepatitis (AIH) were diagnosed from 1990 to 2003 in the area of the Hospital de Sagunto (Valencia, Spain), which attends a population of 112,003 inhabitants aged more than 14 years (54,622 males and 57,381 females). The diagnostic criteria of the International Autoimmune Hepatitis Group were used and patients who, despite having a probable diagnosis of AIH, presented hepatitis C virus infection were excluded. The diagnosis was probable in one patient and definitive in 12. All patients, 11 females and two males aged 45.9 12.2 years (range: 28-66), were classified as AIH type 1. Among the population aged more than 14 years, the mean annual incidence of AIH was 0.83 cases/100,000 inhabitants (95% CI, 0.44-1.42) (range: 0-2.68), showing a significant trend to increase (b = 0.132; p = 0.019). The incidence was higher in women than in men (RR = 5.24; 95% CI, 1.16-23.62). The mean annual incidence was 1.37 (95% CI, 0.68-2.46) (range: 0-3,49) in women and was 0.26 (95% CI, 0.02-0.96) (range: 0-1.83) in men. By age, the maximum mean annual incidence was observed in the group aged 55-64 years (1.6 cases/100,000 inhabitants). The prevalence of AIH in September 2003 was 11.61 cases/100,000 inhabitants aged more than 14 years (95% CI, 6.78-19.86). The prevalence was 3.66 (95% CI, 1-13.35) in men and was 19.17 (95% CI, 10.70-34.33) in women.

Incidence, clinical spectrum, and outcomes of primary sclerosing cholangitis in a United States community

BACKGROUND & AIMS

The epidemiology of primary sclerosing cholangitis (PSC) in the United States is unknown. We report the incidence, clinical spectrum, and outcomes of PSC in Olmsted County, Minnesota.

METHODS

Using the Rochester Epidemiology Project, a medical records linkage system in Olmsted County, Minnesota, we identified county residents with PSC, and the diagnosis was confirmed according to clinical, biochemical, radiographic, and histologic criteria.

RESULTS

Twenty-two patients met diagnostic criteria for PSC in 1976-2000. The age-adjusted (to 2000 U.S. whites) incidence of PSC in men was 1.25 per 100,000 person-years (95% CI, 0.70 to 2.06) compared with 0.54 per 100,000 person-years (95% CI, 0.22 to 1.12) in women. The prevalence of PSC in 2000 was 20.9 per 100,000 men (95% CI, 9.5 to 32.4) and only 6.3 per 100,000 women (95% CI, 0.1 to 12.5). Seventy-three percent of cases had inflammatory bowel disease, the majority with ulcerative colitis. Survival among PSC patients was significantly less than expected for the Minnesota white population of similar age and gender (P < 0.001).

CONCLUSIONS

These data represent the first population-based estimates of the incidence and prevalence of PSC in the United States. The incidence and prevalence of PSC were approximately one third of those previously described for primary biliary cirrhosis in the same population. Our data suggest that the prevalence of PSC in the United States, with its attendant medical burdens, is significantly greater than previously estimated.

The epidemiology of primary biliary cirrhosis

Over the last 30 years, many studies have reported on the epidemiology of PBC. Substantial increases in prevalence were noted in the majority of studies examining longitudinal data, and several have reported increases in the incidence of PBC. Furthermore, although it is difficult to compare studies directly, as methods of case ascertainment have greatly improved over this period, there has been a definite trend toward increasing prevalence (and also possibly incidence) across studies. Together, these data strongly suggest that in many countries, the frequency with which PBC is diagnosed has increased considerably between 1980 and the present time. The reasons for this change may be complex. There may have been a true increase in the incidence of PBC, reflecting either increased exposure to a currently unknown environmental etiological agent or demographic changes with an increased elderly, at-risk population. The prevalence may have further increased due to increased survival of patients, either due to improved care or earlier diagnosis. Some of the apparent increase in PBC frequency may also be artifactual, however, resulting from increased use of diagnostic tests, particularly autoantibody screens. This may be due to increased availability of testing, increased clinician (or patient) awareness of PBC, increased use of testing in well-person screening, or increased investigation of ill-defined symptoms. Furthermore, there may also have been an improvement in clinicians' ability to recognize PBC on the basis of the clinical picture (in one study, 37% of patients whose clinical results indicated a diagnosis of PBC were not recognized by the clinician caring for the patient at that time). The last factor alone suggests that all studies based only upon cases known to interested clinicians have probably substantially underestimated the prevalence of disease. Whatever the reason, the recognized epidemiology of PBC has dramatically changed over the past 30 years. It is now a frequent cause of liver morbidity, and patients with PBC are significant users of health resources, including liver transplantation. Large geographical variations in disease frequency, both between and within studies, tantalizingly suggest the presence of as-yet-unidentified risk factors. This should be further followed up with new analytical epidemiological studies. Only two case control studies have examined risk factors for PBC, and these have been either relatively small or used poorly defined and potentially biased experimental groups. These need repeating in new settings. We suggest that, as with other diseases, modern epidemiological instruments used in well-designed studies may provide important clues to the cause or causes of this disease.

Autoimmune liver disease

Autoimmune hepatitis can affect diverse ethnic groups, and its clinical expression and outcome can vary accordingly. An asymptomatic presentation may identify patients who respond more readily to medication. Celiac sprue is important to recognize and treat by gluten restriction. Centrilobular necrosis and coincidental destructive cholangitis do not preclude the diagnosis, and antibodies to soluble liver antigen/liver pancreas may identify patients susceptible to relapse. Women, who have non-DRB1*0401 DR4 alleles more commonly than do men, may respond to a diverse range of autoantigens. DRB1*1301 is associated with autoimmune hepatitis in Brazil, especially among children, and it may favor an indigenous triggering agent. Variant syndromes are heterogenous conditions that probably reflect referral biases, and molecular mimicry between foreign and self-antigens is the basis for most theories of pathogenesis. Immunosuppressive medications (eg, cyclosporine, mycophenolate mofetil) have been used empirically with success, and recurrent and de novo disease after liver transplantation must be considered in all patients with graft dysfunction.