Autoimmune Hepatitis

Abstract

Autoimmune hepatitis is characterized by inflammatory liver histology, circulating nonorgan-specific autoantibodies, and increased levels of immunoglobulin G, in the absence of a known etiology. Two types of juvenile autoimmune hepatitis (AIH) are recognized according to seropositivity for smooth muscle and/or anti-nuclear antibody (AIH type 1) or liver kidney microsomal antibody (AIH type 2). There is a female predominance in both. AIH type 2 presents more acutely, at a younger age and commonly with immunoglobulin A deficiency, whereas duration of symptoms before diagnosis, clinical signs, family history of autoimmunity, presence of associated autoimmune disorders, response to treatment, and long-term prognosis are similar in the 2 groups. Immunosuppressive treatment with steroids and azathioprine, which should be instituted promptly to avoid progression to cirrhosis, induces remission in 80% of cases. Relapses are common, often due to nonadherence. Drugs effective in refractory cases include cyclosporine and mycophenolate mofetil. Long-term treatment is usually required, with only some 20% of AIH type 1 patients able to discontinue therapy successfully. In childhood, sclerosing cholangitis with strong autoimmune features, including interface hepatitis and serological features identical to AIH type 1, is as prevalent as AIH, but it affects boys and girls equally. Differential diagnosis relies on cholangiographic studies. In autoimmune sclerosing cholangitis liver parenchymal damage responds satisfactorily to immunosuppressive treatment, whereas bile duct disease tends to progress. In this article we review the state of the art of diagnosis, monitoring, and treatment for children with AIH.

A girl with type 1 diabetes and a yellowish appearance

“…The trigger that initiates autoimmunity in the first place, however, is ill-defined. Both in type 1 diabetes and autoimmune hepatitis an underlying genetic predisposition has been suggested, because both diseases are associated with certain HLA, especially HLA DR3 and DR4 3 8. For example, in Northern Europe type 1 autoimmune hepatitis is associated with the presence of HLA DRB1*03,17 for which the girl in the present case was heterozygote.…”

“…The presence of anti-LC-1 has also been associated with autoimmune hepatitis type 2 8. Both types occur predominantly in females.…”

Pediatric Autoimmune Hepatitis in a Patient Who Presented With Erythema Nodosum: A Case Report

“…The causative factor of AIH is not clearly known; however, an extrinsic factor is believed to activate a T-cell-mediated response against hepatocyte antigen in patients with genetic susceptibility [1][2]. We report the case of an 8-year-old girl with AIH who presented with EN as the initial manifestation.…”

“…AIH occurs in adults and children of all ages, mainly affecting females, and it occasionally has a fluctuating course, with periods of increased or diminished activity. AIH responds dramatically to immunosuppressive therapy, but when left untreated, it progressively and rapidly develops into cirrhosis and liver failure [2][3]. AIH is responsible for approximately 2-5% of chronic liver diseases in children.…”

“…Its incidence in Europe is 0.69 per 100,000 of the adult population. The prevalence of pediatric AIH has not been documented [2][3][4][5]. AIH often follows a more acute and aggressive course in children and young adults than in middle-aged and elderly patients [6].…”