Other causes of hepatitis:
Viral hepatitis - it is necessary to distinguish autoimmune hepatitis from acute hepatitis caused by Hepatitis A/B/C/D/E, herpes simplex, varicella zoster, EBV, CMV virus
Drug-induced liver injury - portal neutrophils are more prevalent in drug-induced liver injury on liver biopsy and can help distinguish the two
Nonalcoholic steatohepatitis - related medical history and liver biopsy showing fatty infiltration and the presence of neutrophils and central fibrosis can distinguish the two
Lupus-associated liver disease - rarely presents with elevated ASMA or AMA antibodies
Acute liver failure - people with acute liver failure may have elevated autoantibodies but the antibodies alone are not enough for the diagnosis of autoimmune hepatitis
Iron overload - elevated iron in the body can cause liver inflammation

Treatment
The choice for medical treatment should be based on the individuals severity of symptoms, quantitative elevation of liver enzymes and antibody levels, findings on liver biopsy, and ability to tolerate side effects of medical therapy. Generally, treatment is not required in asymptomatic patients with normal liver enzyme and antibody levels and liver biopsies that do not demonstrate inflammation because these patients are at a low risk of disease progression. In symptomatic individuals with evidence of interface hepatitis and necrosis on liver biopsy, it is recommended to offer treatment especially if the patient is young and can tolerate the side effects of medical therapy.The mainstay of treatment involves the use of immunosuppressive glucocorticoids such as prednisone during acute episodes and resolution of symptoms can be achieved in up to 60–80% of cases, although many will eventually experience a relapse.
Rarely, rash or unexplained fever may appear. In women, the absence of menstruation (amenorrhoea) is a frequent feature. Physical examination may be normal, but it may also reveal signs and symptoms of chronic liver disease. Many people have only laboratory abnormalities as their initial presentation, as unexplained increase in transaminases and are diagnosed during an evaluation for other reasons. Others have already developed cirrhosis at diagnosis. Of note, alkaline phosphatase and bilirubin are usually normal. Autoimmune hepatitis may overlap with other autoimmune conditions, mainly type 1 diabetes mellitus, ulcerative colitis, lupus, celiac disease, vasculitis, and autoimmune thyroiditis. Cause
The prevailing theory for the development of autoimmune hepatitis is thought to be the interplay of genetic predisposition, an environmental trigger (virus, drugs, herbs, immunizations), and failure of the native immune system resulting in chronic inflammation of hepatocytes and subsequent fibrosis of the liver.There is no specific evidence of the cause. Sixty percent of patients have findings associated with chronic hepatitis but without serologic evidence of a viral infection. The disease is strongly associated with anti-smooth muscle autoantibodies.The exact genes and triggers responsible remain undefined, but studies show association of early-onset, severe disease with the HLA-DR3 serotype and late-onset disease with the HLA-DR4 serotype. Diagnosis
The diagnosis of autoimmune hepatitis is best achieved with a combination of clinical, laboratory, and histological findings after excluding other etiological factors (e.g. viral, hereditary, metabolic, cholestatic, and drug-induced liver diseases). The requirement for histological examination necessitates a liver biopsy, typically performed with a needle by the percutaneous route, to provide liver tissue.