Extreme hyperglobulinemia in subacute hepatic necrosis

Autoimmune Hepatitis: Epidemiology, Subtypes, and Presentation

Autoimmune hepatitis (AIH) is a chronic immunologic disorder in which the immune system targets the liver. The disease has a genetic basis and this accounts for the epidemiologic variation observed in serologic testing and clinical presentation across different populations. The incidence of AIH increases with age into the 70s and seems to be increasing in prevalence. Most patients test positive for antinuclear antibody, ASMA, or anti-LKM but about 20% of patients do not have these serologic markers. At clinical presentation, patients may be asymptomatic, symptomatic, have acute liver failure, or decompensated cirrhosis.

Fashioning the immunological self: the biological individuality of F. Macfarlane Burnet

During the 1940s and 1950s, the Australian microbiologist F. Macfarlane Burnet sought a biologically plausible explanation of antibody production. In this essay, we seek to recover the conceptual pathways that Burnet followed in his immunological theorizing. In so doing, we emphasize the influence of speculations on individuality, especially those of philosopher Alfred North Whitehead; the impact of cybernetics and information theory; and the contributions of clinical research into autoimmune disease that took place in Melbourne. We point to the influence of local experimental and intellectual currents on Burnet's work. Accordingly, this essay describes an arc distinct from most other tracings of Burnet's conceptual development, which focus on his early bacteriophage research, his fascination with the work of Julian Huxley and other biologists in the 1920s, and his interest in North Atlantic experimental investigations in the life sciences. No doubt these too were potent influences, but they seem insufficient to explain, for example, Burnet's sudden enthusiasm in the 1940s for immunological definitions of self and not-self. We want to demonstrate here how Burnet's deep involvement in philosophical biology - along with attention to local clinical research - provided him with additional theoretic tools and conceptual equipment, with which to explain immune function.

A 50-year experience with autoimmune hepatitis: and where are we now?

BACKGROUND

Autoimmune hepatitis (AIH) as chronic active hepatitis became recognized in the 1940s as a progressive hyperglobulinemic disease affecting younger women attributed to persisting virus infection of the liver: autoimmunity then was barely on the horizon.

EARLY OBSERVATIONS

The lupus erythematosus (LE) cell reported in 1948 signified the presence of antinuclear autoantibodies, promoting perceptions of autoimmunity in certain chronic diseases. Recognition of LE cells in chronic hepatitis led to the designation of 'lupoid hepatitis', with autoimmunity further substantiated by anti-cytoplasmic autoantibodies detected by complement fixation. Next a serum reactant with smooth muscle of rodent stomach was found to have a wider distribution and became identified as an autoantibody to filamentous (F) actin. Therapy with corticosteroids proved effective, particularly combined with azathioprine. Various trials showed greatly improved survival and established modern therapy of AIH. An HLA-based predisposition (B8, DR3) was the first pointer to a genetic etiology.

RECENT ADVANCES

Recombinant or purified autoantigenic substrates have led to automated assays, which, together with improved immunofluorescence procedures, allow serological confidence in diagnosis and institution of effective immunosuppressive therapies. The liver-kidney 'microsomal' autoantigen reactive with cytochrome P450 2D6 distinguishes two serological types of AIH that appear pathogenetically distinct. Molecular characterization of antigens and epitopes remains wanting in type 1 AIH.

FUTURE PROSPECTS

The challenge remains with both types of AIH to elucidate in molecular terms the genetic and environmental basis of pathogenesis from initiation to ultimate progression and cirrhosis (when inadequately treated). Advancing technologies are bringing this goal closer to being attainable.

Historical reflections on autoimmune hepatitis

Autoimmune hepatitis (AIH), initially known as chronic active or active chronic hepatitis (and by various other names), first came under clinical notice in the late 1940s. However, quite likely, chronic active hepatitis (CAH) had been observed prior to this and was attributed to a persistently destructive virus infection of the liver. An earlier (and controversial) designation in 1956 as lupoid hepatitis was derived from associated L.E. cell test positivity and emphasized accompanying multisystem features and immunological aberrations. Young women featured prominently in early descriptions of CAH. AIH was first applied in 1965 as a descriptive term. Disease-characteristic autoantibodies were defined from the early 1960s, notably antinuclear antibody (ANA), smooth muscle antibody (SMA) and liver-kidney microsomal (LKM) antibody. These are still widely used diagnostically but their relationship to pathogenesis is still not evident. A liver and disease specific autoantigen has long been searched for but unsuccessfully. Prolonged immunosuppressive therapy with predisolone and azathioprine in the 1960s proved beneficial and remains standard therapy today. AIH like many other autoimmune diseases is associated with particular HLA alleles especially with the "ancestral" B8, DR3 haplotype, and also with DR4. Looking forwards, AIH is one of the several enigmatic autoimmune diseases that, despite being (relatively) organ specific, are marked by autoimmune reactivities with non-organ-specific autoantigens. New paradigms are needed to explain the occurrence, expressions and pathogenesis of such diseases.

Pathogenesis of autoimmune hepatitis

Autoimmune hepatitis (AIH) is an idiopathic disorder affecting the hepatic parenchyma. There are no morphological features that are pathognomonic of the condition but the characteristic histological picture is that of an interface hepatitis without other changes that are more typical of other liver diseases. It is associated with hypergammaglobulinaemia, high titres of a wide range of circulating auto-antibodies, often a family history of other disorders that are thought to have an autoimmune basis, and a striking response to immunosuppressive therapy. The pathogenetic mechanisms are not yet fully understood but there is now considerable circumstantial evidence suggesting that: (a) there is an underlying genetic predisposition to the disease; (b) this may relate to several defects in immunological control of autoreactivity, with consequent loss of self-tolerance to liver auto-antigens; (c) it is likely that an initiating factor, such as a hepatotropic viral infection or an idiosyncratic reaction to a drug or other hepatotoxin, is required to induce the disease in susceptible individuals; and, (d) the final effector mechanism of tissue damage probably involves auto-antibodies reacting with liver-specific antigens expressed on hepatocyte surfaces, rather than direct T-cell cytotoxicity against hepatocytes.

Auto-antibodies in chronic active hepatitis may bind to cancer antigens

Auto-antibodies in auto-immune chronic active hepatitis (AICAH) are hypothesized to bind to cancer antigens.

Chronic hepatitis: pathogenesis and treatment

Current therapies for chronic viral hepatitis, autoimmune "lupoid" chronic active hepatitis, and drug-induced chronic hepatitis are discussed in the context of recent advances in our understanding of the pathophysiology of chronic active liver disease. Accurate diagnosis is the cornerstone of proper treatment; the limitations and pitfalls of conventional techniques are discussed. Current theories of the pathogenesis of chronic hepatitis B are reviewed to provide a framework for the use of antiviral drugs. Data from the early results of therapy with adenine arabinoside, acyclovir, and immunomodulatory agents are reviewed, and the theoretical basis for the use of alpha-interferon as well as preliminary data supporting its efficacy is presented. Strategies for the treatment of chronic delta hepatitis and chronic non-A, non-B viral hepatitis are discussed as well. The immunological changes associated with autoimmune chronic active hepatitis are described to help define those patients with chronic active hepatitis who are likely to respond to immunosuppressive therapy. The recognized hazards of long-term corticosteroid therapy are indicated and guidelines for the management of these patients are suggested. Chronic drug-induced liver disease will usually improve with cessation of the offending agent. An approach to the patient with suspected drug-induced chronic hepatitis is indicated. Finally, the role of liver transplantation is mentioned as the ultimate treatment modality available for endstage liver disease.

ACTIVE 'JUVENILE' CIRRHOSIS CONSIDERED AS PART OF A SYSTEMIC DISEASE AND THE EFFECT OF CORTICOSTEROID THERAPY

This is a clinical study of 81 patients (32 male and 49 female), who are not alcoholics, with jaundice of hepato-cellular type lasting longer than three months. Forty-nine of these patients were under 21 years of age. The natural history of the condition and the response to corticosteroid therapy is described; good symptomatic relief can be achieved with corticosteroids but they do not seem to prolong life. The aetiology is discussed with special reference to the relationship to viral hepatitis, to systemic lupus erythematosus, and to other disturbances of immunity.