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Epidemiology of vitiligo and associated autoimmune diseases in Caucasian probands and their families.

Generalized vitiligo is an autoimmune disorder characterized by acquired white patches of skin and overlying hair, the result of loss of melanocytes from involved areas. The most common disorder of pigmentation, vitiligo occurs with a frequency of 0.1-2.0% in various populations. Family clustering of cases is not uncommon, in a non-Mendelian pattern suggestive of multifactorial, polygenic inheritance. We surveyed 2624 vitiligo probands from North America and the UK regarding clinical characteristics, familial involvement, and association with other autoimmune disorders, the largest such survey ever performed. More than 83% of probands were Caucasians, and the frequency of vitiligo appeared approximately equal in males and females. The frequency of vitiligo in probands' siblings was 6.1%, about 18 times the population frequency, suggesting a major genetic component in disease pathogenesis. Nevertheless, the concordance of vitiligo in monozygotic twins was only 23%, indicating that a non-genetic component also plays an important role. Probands with earlier disease onset tended to have more relatives affected with vitiligo, suggesting a greater genetic component in early onset families. The frequencies of six autoimmune disorders were significantly elevated in vitiligo probands and their first-degree relatives: vitiligo itself, autoimmune thyroid disease (particularly hypothyroidism), pernicious anaemia, Addison's disease, systemic lupus erythematosus, and probably inflammatory bowel disease. These associations indicate that vitiligo shares common genetic aetiologic links with these other autoimmune disorders. These results suggest that genomic analysis of families with generalized vitiligo and this specific constellation of associated autoimmune disorders will be important to identify the mechanisms of genetic susceptibility to autoimmunity.

Adolescent↗

Genetic susceptibility to the development of autoimmune disease.

1. Autoimmune diseases are common conditions which appear to develop in genetically susceptible individuals, with expression of disease being modified by permissive and protective environments. Familial clustering and data from twin studies provided the impetus for the search for putative loci. Both the candidate gene approach in population-based case-control studies and entire genome screening in families have helped identify susceptibility genes in a number of autoimmune diseases. 2. After the first genome screen in type 1 (insulin-dependent) diabetes mellitus it seems likely that most autoimmune diseases are polygenic with no single gene being either necessary or sufficient for disease development. Of the organ-specific autoimmune diseases, genome screens have now been completed in insulin-dependent diabetes mellitus and multiple sclerosis. Furthermore, the clustering of autoimmune diseases within the same individuals suggests that the same genes may be involved in the different diseases. This is supported by data showing that both HLA (human leucocyte antigen) and CTLA-4 (cytotoxic T-lymphocyte-associated-4) appear to be involved in the development of insulin-dependent diabetes mellitus and Graves' disease. 3. Genome screens have also been completed in some of the non-organ-specific autoimmune diseases including rheumatoid arthritis, inflammatory bowel disease and psoriasis. Many candidate genes have also been investigated although these are predominantly in population-based case-control studies. 4. Substantial progress has been made in recent years towards the identification of susceptibility loci in autoimmune diseases. The inconsistencies seen between case-control studies may largely be due to genetic mismatching between cases and controls in small datasets. Family-based association studies are being increasingly used to confirm genetic linkages and help with fine mapping strategies. It will, however, require a combination of biology and genetics, as has been necessary with the major histocompatibility complex in insulin-dependent diabetes mellitus, to identify primary aetiological mutations.

Abatacept↗

Animal models of autoimmune liver disease.

Autoimmune liver diseases in humans are characterized by chronic active hepatitis with serum autoantibodies, hypergammaglobulinemia and liver pathology showing necroinflammatory disease and fibrosis. There are an increasing number of autoantigens believed to be associated with various autoimmune liver diseases. This review will briefly outline human autoimmune hepatitis and the immunology of the liver. Various murine models of liver inflammation will be discussed, including transgenic and non-transgenic models, with emphasis on how these models aid in our knowledge of the mechanisms of disease development and chronicity. There are limitations with all of the models, including a preponderance of T-cell-focused responses. Murine models do not easily develop fibrosis, a hallmark of autoimmune hepatitis in humans. Different experimental models may not reach the same conclusions with differences between immune responses. However, this multiplicity of responses does not necessarily imply that these models are inappropriate for the study of liver immunology and autoimmune liver diseases, as different autoantigens may induce different liver responses. Knowledge of how the liver differs from other immune organs is essential to further our understanding of liver-specific autoimmunity. The plethora of antigens implicated in autoimmune hepatitis in humans predicts that multiple mechanisms may play a role in precipitating disease in the susceptible individual.

Animals↗

Lichen sclerosus in adult men: a study of HLA associations and susceptibility to autoimmune disease.

Lichen sclerosus is a skin disorder of unknown prevalence affecting both men and women, and several studies have established HLA associations in women with this disease. Autoimmune disease associations in the form of a personal and/or family history of autoimmune disease have also been shown to be related to lichen sclerosus. In this study, we examined 58 men (mean age 38 years) with lichen sclerosus, 39 of whom had histologically proven disease. HLA tissue typing by phototyping was performed on these patients and contrasted with that of 602 control subjects. There was no difference in antigen frequencies of the HLA class I loci. The patient group was found to have an increased frequency of several HLA antigens of the class II loci: DR11, 13 of 58 (22%) patients vs. 75 of 602 (13%) control subjects (P = 0.05); DR12, five of 58 (9%) patients vs. 16 of 602 (3%) control subjects (P = 0.04); DQ7, 26 of 58 (45%) patients vs. 189 of 602 (31%) control subjects (P = 0.05). There were few autoimmune disease associations: two of 58 (3%) patients had a personal history of a different autoimmune disease, two patients were found to have abnormal thyroid function and six of 58 (10%) had a first-degree relative with an autoimmune disease. There was no difference in the frequency of the autoimmune haplotype HLA A1, B8, DR3/17, DQ2 compared with the control population. HLA DQ7 has now been shown to occur more frequently in both male and female patients with lichen sclerosus, which may reflect the immunopathogenesis of the disease. Autoimmune disease associations, however, are less common in men with lichen sclerosus.

Adult↗

Secondary adrenal insufficiency associated with autoimmune disorders: a report of twenty-five cases.

OBJECTIVE: Addison's disease is frequently a component of autoimmune polyendocrinopathies while secondary adrenal insufficiency associated with autoimmune disorders is believed to be a rare event. We present a series of patients with secondary adrenal insufficiency coexisting with autoimmune diseases and/or antithyroid autoantibodies. DESIGN AND PATIENTS: Among a group of 102 patients with secondary adrenal failure of unknown origin diagnosed at the Department of Endocrinology of the Centre for Postgraduate Medical Education (Warsaw, Poland) we have identified a group with associated autoimmune disorders. Thyroid abnormalities occurred most frequently. Other diseases included insulin-dependent diabetes mellitus, pernicious anaemia, vitiligo, premature ovarian failure and autoimmune thrombocytopaenia. There were 23 women and one man aged 17-72 years at the time of investigation. Additionally, we included a woman with Addison's disease in whom the ACTH deficiency appeared 18 years after the onset of primary adrenal hypofunction. MEASUREMENTS: Pituitary-adrenal function tests comprised urinary excretion of 17-hydroxycorticosteroids in basal conditions and during a 2-day tetracosactrin test, plasma concentrations of ACTH and cortisol, and a 2-day metyrapone test (in eight cases). Thyroid function and immunity tests were: TSH, thyroxine, the antithyroglobulin, antimicrosomal and anti-peroxidase autoantibodies. Other endocrine studies included: serum LH, FSH and PRL. RESULTS: The 17-hydroxycorticosteroid values, both basally and during stimulation tests were consistent with a diagnosis of secondary adrenal insufficiency. Serum cortisol and plasma ACTH concentrations were low. In 14 patients primary hypothyroidism was confirmed by low T4 levels. In three patients subclinical primary hypothyroidism was revealed (elevated TSH levels). Three patients who had a past history of Graves' disease were euthyroid at the time of investigation. Twenty-three patients had antibodies against peroxidase. Most patients had gonadotrophins and PRL values within normal limits. CONCLUSIONS: The co-existence of autoimmune disorders with secondary adrenal insufficiency suggests an autoimmune aetiology for the ACTH deficiency.

Adolescent↗

Autoimmune complications of chronic lymphocytic leukemia.

Autoimmune complications are common in chronic lymphocytic leukemia (CLL), occurring in up to a quarter of all patients during the course of the illness. By far the most common manifestation is autoimmune hemolytic anemia (AIHA), followed by immune thrombocytopenia (ITP). It is not true to say that autoimmunity is confined to the formed elements of the blood since conditions such as paraneoplastic pemphigus and acquired angioedema do occur in CLL, but nonhematologic autoimmunity is very rare indeed. The pathogenesis of autoimmunity in CLL is unknown. It may be related to the ability of the CLL cells to act as antigen-presenting cells (APCs), and to process antigen (particularly the Rh protein) so as to reveal cryptic peptides that are seen as foreign by helper T cells. It is likely that a failure of regulatory T-cell function is also involved. Autoimmune episodes may be triggered by treatment, particularly with purine analogues. Such episodes are often severe and may be fatal. Treatment of CLL-associated autoimmunity follows conventional protocols, but non-response to primary treatments is not uncommon. Promising results have been obtained with cyclosporine and rituximab.

Autoimmune Diseases↗

There is no evidence of an inverse relationship between TH2-mediated atopy and TH1-mediated autoimmune disorders: Lack of support for the hygiene hypothesis.

BACKGROUND: The findings of an inverse relationship between T(H)1- and T(H)2-mediated disorders would provide strong empiric support to the hygiene hypothesis. OBJECTIVE: We sought to investigate the relationship between T(H)2-mediated atopic allergy and T(H)1-mediated autoimmune conditions in a nationally representative population. METHODS: We used logistic regression to analyze adult data from the Third National Health and Nutrition Examination Survey. Data on allergic and autoimmune disease history were available for 20,050 subjects, and data on atopy were available for a subsample of 7304 subjects. Atopy was defined by one or more positive skin prick test responses (wheal of > or =3 mm) to 10 common aeroallergens. Allergic disease was defined by patient reports of physician-diagnosed asthma, hay fever, or both. T(H)1-mediated autoimmune disease was defined by patient reports of physician-diagnosed type 1 diabetes mellitus, thyroid disorders, and/or rheumatoid arthritis. RESULTS: Adjusted for age and sex and taking into account the complex survey design, there was no relationship between atopy and a history of autoimmune disorders (adjusted odds ratio, 1.01; 95% CI, 0.61-1.67; P =.97). In contrast, physician diagnosis of allergic disorders was associated with a significant increased risk of physician-diagnosed autoimmune disorders (adjusted odds ratio, 1.67; 95% CI, 1.35-2.07; P <.001). CONCLUSION: We found no evidence of an inverse relationship between atopy and patient reports of physician-diagnosed common autoimmune disorders in the adult American population. Contrary to our initial hypothesis, reports of physician-diagnosed common allergic disorders are positively associated with reports of physician-diagnosed autoimmune disorders, with this possibly being caused by ascertainment bias. These findings suggest that the T(H)1/T(H)2 paradigm might be an oversimplification.

Adolescent↗

Inhibition of FLT3 signaling targets DCs to ameliorate autoimmune disease.

Autoimmune diseases often result from inappropriate or unregulated activation of autoreactive T cells. Traditional approaches to treatment of autoimmune diseases through immunosuppression have focused on direct inhibition of T cells. In the present study, we examined the targeted inhibition of antigen-presenting cells as a means to downregulate immune responses and treat autoimmune disease. Dendritic cells (DCs) are the central antigen-presenting cells for the initiation of T cell responses, including autoreactive ones. A large portion of DCs are derived from hematopoietic progenitors that express FLT3 receptor (CD135), and stimulation of the receptor via FLT3 ligand either in vivo or in vitro is known to drive expansion and differentiation of these progenitors toward a DC phenotype. We hypothesized that inhibition of FLT3 signaling would thus produce an inhibition of DC-induced stimulation of T cells, thereby inhibiting autoimmune responses. To this end, we used small-molecule tyrosine kinase inhibitors targeted against FLT3 and examined the effects on DCs and their role in the promulgation of autoimmune disease. Results of our studies show that inhibition of FLT3 signaling induces apoptosis in both mouse and human DCs, and thus is a potential target for immune suppression. Furthermore, targeted inhibition of FLT3 significantly improved the course of established disease in a model for multiple sclerosis, experimental autoimmune encephalomyelitis, suggesting a potential avenue for treating autoimmune disease.

Animals↗

Mast cells and innate cytokines are associated with susceptibility to autoimmune heart disease following coxsackievirus B3 infection.

The development of autoimmune disease involves a combination of genetic and environmental factors. Many autoimmune diseases are believed to be triggered by viral infections. Since the early, natural immune response to infection can determine the later development of the adaptive immune response, innate immunity likely influences the progression from viral immunity to autoimmunity. To investigate the role of the innate immune response on susceptibility to autoimmune disease, we compared the early cytokine response of mice susceptible or resistant to the development of autoimmune heart disease following viral infection. We found that susceptible BALB/c mice produced elevated levels of TNF-alpha, IL-1beta, and IL-4 within hours of Coxsackievirus B3 (CB3) infection. These cytokines are known to be critical for the development of autoimmune heart disease, and are also rapidly produced from activated mast cells (MC). Degranulating MC were observed as early as 6 h following CB3 infection in the heart, and significantly higher numbers of MC were found in the spleen of susceptible BALB/c mice at this time. Thus, susceptibility to autoimmune heart disease can be determined as early as 6 h following viral infection in susceptible strains of mice.

Animals↗

Experimental autoimmune panencephalitis and uveoretinitis transferred to the Lewis rat by T lymphocytes specific for the S100 beta molecule, a calcium binding protein of astroglia.

The pathogenic potential of autoimmune T cell responses to nonmyelin autoantigens was investigated in the Lewis rat using the astrocyte-derived calcium binding protein S100 beta, as a model nonmyelin autoantigen. The Lewis rat mounts a vigorous RT1B1 (major histocompatibility complex class II) restricted autoimmune response to an immunodominant S100 beta epitope (amino acid residues 76-91). The adoptive transfer of S100 beta-specific T cell lines induced a severe inflammatory response in the nervous system, but only minimal neurological dysfunction in naive syngeneic recipients. The inability of S100 beta-specific T cell transfer to induce severe disease was associated with a decreased recruitment of ED1+ macrophages into the central nervous system (CNS) in comparison with that seen in severe experimental autoimmune encephalomyelitis (EAE) induced by the adoptive transfer of myelin basic protein (MBP)-specific T line cells. Moreover, unlike encephalitogenic MBP-specific T cell lines, S100 beta-specific T cell lines exhibited no cytotoxic activity in vitro. Histopathological analysis also revealed striking differences in the distribution of inflammatory lesions in MBP- and S100 beta-specific T cell-mediated disease. In contrast to the MBP paradigm, S100 beta-specific T cell transfer induces intense inflammation not only in the spinal cord, but throughout the entire CNS and also in the uvea and retina of the eye. In view of the distribution of lesions throughout the grey and white matter of the CNS we propose to term this new model experimental autoimmune panencephalomyelitis (EAP) to differentiate it from EAE. These experiments demonstrate for the first time that nonmyelin CNS autoantigens can initiate a pathogenic autoimmune T cell response, although the nature of the target autoantigen profoundly influences the clinical and histopathological characteristics of the resulting autoimmune disease. This is not simply a consequence of the distribution of the autoantigen, as both MBP and S100 beta are coexpressed in many areas of the CNS, but reflects differences in the capacity of different regions of the CNS to process and present specific autoantigens. This new model of T cell-mediated autoimmune CNS disease exhibits a number of similarities to multiple sclerosis (MS), such as its mild clinical course and the involvement of areas of the brain and eye, which are absent in myelin-mediated models of EAE. Nonmyelin autoantigens may therefore play an unexpectedly important role in the immunopathogenesis of inflammatory diseases of the CNS.

Amino Acid Sequence↗

Polymorphism of the CTLA-4 gene is associated with autoimmune hypothyroidism in the United Kingdom.

The cytotoxic T-lymphocyte-associated-4 (CTLA-4) molecule plays an important role in immune regulation by downregulating activation of T cells by antigen-presenting cells. Polymorphisms of the CTLA-4 gene have been shown to be associated with susceptibility to a number of autoimmune diseases. Some, but not all, studies suggest association between the CTLA-4 gene and autoimmune hypothyroidism. The aim of this study was to determine whether allelic association was present between the A-G single nucleotide polymorphism (SNP) at position 49 in exon 1 of the CTLA-4 gene and autoimmune hypothyroidism. The study was performed in 158 patients with autoimmune hypothyroidism and 384 control subjects. All subjects were white Caucasians from the United Kingdom. Genotyping was carried out by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) using the restriction enzyme Bbv1. There was a significant excess of the G allele in patients with autoimmune hypothyroidism compared with controls (43% vs. 32% respectively; chi2 = 10.7, p = 0.001; odds ratio 1.57). The GG and the AG genotypes were found to be more frequent in patients with autoimmune hypothyroidism than controls (17% vs. 8.8% and 50% vs. 46% respectively; chi2 = 11.7, p = 0.003). These results suggest that the CTLA-4 gene region on chromosome 2q33 is a susceptibility locus for autoimmune hypothyroidism in the United Kingdom.

Abatacept↗

Ovarian autoimmune disease and ovarian autoantibodies.

Detection of specific autoantibodies remains the most practical clinical and research marker of autoimmune disease. The lack of consensus on ovary specific antibodies as a marker for ovarian autoimmunity has clinical and research consequences. The objective of this review is to summarize the evidence for ovarian autoimmunity and the detection of ovary specific autoantibodies in humans. Evidence favors the presence of an autoimmune disease of the ovary. Ovarian autoantibodies are associated primarily with premature ovarian failure (POF) and unexplained infertility. Variations in detection of ovarian autoantibodies are likely to be due to study design elements such as antibody test format, antigen preparation, and criteria for study and comparison groups. In addition, multiple targets appear to be involved in ovarian autoimmunity including ovarian cellular elements and oocyte related antigens. Many studies only assess one target antigen, leaving individuals with ovarian autoimmunity unidentified. The next most significant advance in characterizing ovarian autoimmunity will be definitive identification of the specific antigens and development of standardized tests based on use of specific antigens.

Autoantibodies↗

Stress and thyroid autoimmunity.

While many studies have shown a connection between stress and autoimmune disease, most of the evidence for stress contributing to the onset and course of autoimmune disease is circumstantial and the mechanisms by which stress affects autoimmune disease are not fully understood. The best circumstantial evidence for an effect of stress on autoimmune thyroid disease is the well-known relationship between the onset of Graves' hyperthyroidism and major stress but even this is debated. However, most of the recent case-control studies have supported stress as a factor that affects the onset and clinical course of Graves' disease. On the other hand, there have been few reports concerning the possible relationship between stress and Hashimoto's thyroiditis. Because the onset and course of Hashimoto's thyroiditis is generally insidious, the effect of stress on Hashimoto's thyroiditis might be overlooked. Numerous human and animal studies have demonstrated that psychological and physiologic stressors induce various immunologic changes. Stress affects the immune system either directly or indirectly through the nervous and endocrine systems. These immune modulations may contribute to the development of autoimmunity as well as the susceptibility to autoimmune disease in genetically predisposed individuals. Stress can be one of the environmental factors for thyroid autoimmunity.

Animals↗

Role of DNA methylation in the regulation of cell function: autoimmunity, aging and cancer.

DNA methylation plays an essential role in maintaining cellular function, and changes in methylation patterns may contribute to the development of autoimmunity, aging and cancer. Evidence for a role in autoimmunity comes from studies demonstrating that inhibiting T lymphocyte DNA methylation causes autoreactivity in vitro and a lupus-like disease in vivo. The autoimmunity is due in part to the heterodimeric beta(2) integrin lymphocyte function-associated antigen-1 (LFA-1) (CD11a/CD18) overexpression, and T lymphocytes from lupus patients hypomethylate the same CD11a promoter sequences, overexpress LFA-1 and demonstrate the same autoreactivity. Procainamide and hydralazine, two drugs that cause a lupus-like disease, also inhibit T cell DNA methylation, increase LFA-1 expression and induce autoreactivity in vitro and autoimmunity in vivo, supporting the association of DNA hypomethylation and autoimmunity. Methylation patterns also change with age in T lymphocytes as well as other tissues, typically with an overall decrease in methylcytosine content, but with increases in some cytosine guanine dinucleotide (CpG) islands. Age-dependent hypomethylation contributes to LFA-1 overexpression with aging, which may play a role in the development of autoimmunity in the elderly and age-dependent methylation of CpG islands in the promoters of tumor suppressor genes is an early event in the development of some cancers. DNA hypomethylation also may contribute to carcinogenesis by promoting overexpression of proto-oncogenes, chromosomal translocations and loss of imprinting. The mechanisms causing altered DNA methylation in autoimmunity, aging and carcinogenesis are incompletely characterized but include exposure to environmental agents and drugs, diet, altered signaling in pathways regulating DNA methyltransferase expression and changes in endogenous regulatory mechanisms. Other mechanisms are likely to be identified as well.

Aging↗

Autoimmune associated recurrent abortions.

A possible relationship between recurrent spontaneous abortions and autoimmune abnormalities was studied. Eight serological autoimmune or autoimmune-correlated parameters were investigated in 91 women with unexplained recurrent abortions (greater than or equal to 3 consecutive, spontaneous abortions) and 89 fertile control women. Five parameters were seen significantly more frequently in 19 women with at least one second trimester miscarriage which had been associated with severe intrauterine growth regardation (IUGR), than in controls. Seventeen of these 19 patients (89%) had at least one positive autoimmune parameter, compared to 15 of 72 patients (21%) with no second trimester abortions with IUGR (P less than 0.0001) and 14 (16%) of the controls (P less than 0.0001). No single autoantibody characterized patients who exhibited a significant accumulation of autoimmune parameters. These findings may suggest that women with recurrent abortions, in whom autoimmunity is thought to play a role, cannot be identified merely by one laboratory assay, such as that for cardiolipin antibodies, but must be defined by positivity of several criteria. Using our own test panel, preliminary clinical and serological criteria have been set up for the definition of an autoimmune-associated recurrent abortion condition. Twenty-three per cent of the patients in our material fulfilled these criteria, and seven out of nine of these women (78%) have to date been treated successfully with heparin/aspirin during pregnancy.

Abortion, Habitual↗

Relation between infection and autoimmunity in mixed cryoglobulinemia.

Mixed cryoglobulinemia (MC) is a systemic vasculitis of small to medium-sized vessels due to the vascular deposition of circulating immune-complexes (CIC) and complement. A leukocytoclastic vasculitis is the histologic hallmark of cutaneous manifestations of the disease, while a clonal B lymphocyte expansion in blood, bone marrow, liver, and spleen represents the underlying pathologic alteration responsible for the production of cryo-CIC and non-cryo CIC with rheumatoid factor activity. A causative role of hepatitis C virus (HCV) infection has been demonstrated in the large majority of MC patients. Hepatitis C virus is both a hepatotropic and a lymphotropic virus; due to this latter biological peculiarity, HCV may trigger a constellation of autoimmune-lymphoproliferative disorders. Besides MC, other important HCV-related diseases are porphyria cutanea tarda, autoimmune hepatitis, membranoproliferative glomerulonephritis, and B cell neoplasias. Hepatitis C virus-related MC represents a link between autoimmune and lymphoproliferative disorders; moreover, MC is an important model to study the complex relation between infections and immune system alterations in humans. During the last years many other autoimmune manifestations have been correlated with HCV infection; namely, sicca syndrome, chronic polyarthritis, polydermatomyositis, fibromyalgia, autoimmune thyroiditis, lung fibrosis, and diabetes mellitus. It is often difficult to verify whether the above associations are coincidental or a pathogenetic link actually exists. At least for particular patients' subsets and in some geographic areas, a causative role of HCV seems to be likely. The geographically heterogeneous distribution of HCV-related autoimmune diseases suggests the contribution of important environmental and genetic factors in the pathogenesis of such conditions. In clinical practice, patients with recent-onset, atypical rheumatic and autoimmune disorders should be carefully investigated for possible HCV infection; this is particularly advisable for correct diagnosis and adequate therapeutic strategy.

Autoimmunity↗

Recurrence of autoimmune hepatitis in children after liver transplantation.

BACKGROUND: Liver transplantation is recognized as the appropriate treatment for end-stage liver disease due to chronic active autoimmune hepatitis. While it was initially thought that the disease did not recur after transplant, it is now generally accepted that adult patients may develop recurrent disease, with studies reporting a recurrence rate of < or = 25%. We have noted a higher incidence of recurrent autoimmune hepatitis in our pediatric patients undergoing liver transplant, with a high incidence of associated morbidity. METHODS: We reviewed the records of six children followed up for autoimmune hepatitis who underwent orthotopic liver transplant for complications of end-stage liver disease. RESULTS: Of the six, five developed recurrent autoimmune hepatitis at a mean time of 11.4 months after transplant. The disease was aggressive, leading to cirrhosis and retransplant in three patients, within 1 year of recurrence. A second recurrence of disease occurred in all three retransplanted patients. One patient has received a third liver transplant, one has died, and one patient is asymptomatic on medical therapy. Autoimmune hepatitis recurred in all four patients receiving tacrolimus. CONCLUSION: We conclude that liver transplant for autoimmune hepatitis is likely to be palliative for most pediatric patients. Potent immunosuppressives such as tacrolimus do not protect against the development of recurrent autoimmune hepatitis.

Adolescent↗

De novo hepatitis with autoimmune antibodies and atypical histology: a rare cause of late graft dysfunction after pediatric liver transplantation.

BACKGROUND: Late graft dysfunction after orthotopic liver transplantation is commonly due to chronic rejection, recurrence of primary disease, sepsis, lympho-proliferative disease, or vascular or biliary complications. Herein we describe a subset of pediatric liver transplant patients in whom late graft dysfunction was associated with autoimmune markers, bile ductular proliferation, and portal infiltrates, which progress to fibrosis. This subset of patients has not been previously described. METHODS: Six of the 115 children followed for greater than 5 years after transplantation developed this unusual form of graft dysfunction. All children were on a low-dose single immunosuppressive therapy (mean trough cyclosporine concentration 89 microg/L) and had been tapered off steroids for a median duration of 1.5 year. Liver biopsies were performed in all children to evaluate the graft dysfunction, and the histologic findings were interpreted by an experienced hepato-pathologist. All patients were tested for antibodies to hepatitis C virus, hepatitis B surface antigen, and IgM antibodies to hepatitis A. Smooth muscle antibody, antinuclear antibody, and antibody to liver/kidney microsome type 1 were sought by indirect immunofluorescence. International Autoimmune Hepatitis Group scores were calculated. All patients underwent ultrasonography with doppler studies at the onset of graft dysfunction. Three patients with marked bile duct proliferation on histology had cholangiograms. RESULTS: Histology in all patients showed mononuclear cell infiltrates in the portal area with interface hepatitis, portal fibrosis, and ductular proliferation without duct damage or loss. All six patients had positive antinuclear antibody or smooth muscle antibody titers. Viral studies for hepatitis A, B, and C were negative in all patients. On the International Autoimmune Hepatitis Group scoring system, five patients had probable autoimmune hepatitis (score of 10-15) and one had definite autoimmune hepatitis (score > 15) at the onset of graft dysfunction. All were treated with azathioprine and prednisone similar to treatment for autoimmune hepatitis. However, despite aggressive treatment, four patients developed bridging portal fibrosis resulting in graft loss in two patients. CONCLUSION: This clinical constellation is associated with worse outcome then that previously described for pediatric patients with posttransplantation de novo autoimmune hepatitis. Further studies are needed to find an optimal treatment regimen for these patients.

Adolescent↗