43,44,182 At the time of diagnosis, cirrhosis is present in ∼25% of patients.183,184 Antibodies to SLA have emerged as possible prognostic markers that may identify patients with severe AIH who are prone to relapse after corticosteroid withdrawal.134,137-140,179,185 Type 2 AIH is characterized by the presence of anti-LKM1112 and/or

anti-LC1 and/or anti-LKM-3. Most patients with type 2 AIH are children, and serum immunoglobulin levels are usually elevated except for the concentration of IgA, which may be reduced.112 Concurrent immune diseases are common,112 progression to cirrhosis occurs,112 and an acute severe presentation is possible.58,64 Recommendations: 5. check details Classification of autoimmune hepatitis into two types based on the presence of ANA and SMA (type 1 AIH) or anti-LKM1 and anti-LC1 (type 2 AIH) can be used to characterize the clinical syndrome

or to indicate serological homogeneity in clinical investigations. Anti-LKM1 antibodies should be routinely investigated to avoid overlooking type 2 AIH. (Class IIa, Level C) PSC and PBC can have clinical, laboratory, histological, and genetic findings that resemble those of AIH,95,206-212 and AIH can have features that resemble each of these cholestatic syndromes.36,81,82,213-217 These nonspecific shared features can confound the codified diagnostic scoring system.13,76,78 The prevalence of AIH among patients with PSC was determined to be 21%-54% using the original scoring system,218,219 but this prevalence decreased to 8% in PSC when the revised original Midostaurin scoring system was

applied.206,220,221 Application of the original scoring system in a retrospective review of 141 patients with PBC showed that 19% and 0% scored as probable and definite AIH, respectively.222 Clinical 上海皓元 judgment is required to determine the predominant phenotype of the disease and to manage the process appropriately.95,223 AIH patients may demonstrate serological features that suggest another diagnosis. AMA occur in about 5% of AIH patients in the absence of other biliary features (“serological overlap”),178,224-228 and their presence may confound the clinical diagnosis. AMA may disappear226 or persist as long as 27 years without an evolution into PBC.227 The revised original scoring system can render a diagnosis of “probable AIH” in these patients, if other features of AIH are sufficiently strong.229,230 Other acute and chronic liver diseases of diverse etiologies that can have serological features of AIH include alcoholic231 and nonalcoholic fatty liver disease,232,233 acute234 and chronic54,235-241 viral hepatitis, and drug-induced hepatitis.242,243 Drugs such as minocycline,244-246 diclofenac,247,248 infliximab,249 propylthiouracil,250 atorvastatin,251 nitrofurantoin,252 methyl dopa,253 and isoniazid254 can cause a syndrome that resembles AIH replete with autoantibodies that generally disappear after discontinuation of the drug.