Internal Medicine

P1: SBT

0521779407-05 CUNY1086/Karliner 0 521 77940 7 June 4, 2007 20:49

202 Autoimmune Hepatitis (AIH)

■Vague upper abdominal pain, pruritus, anorexia, polymyalgia, epis-

taxis, bleeding gums, easy bruisability are also frequent complaints

■Triad of acne, amenorrhea, & arthralgia may be seen in adolescent

females

■Acute hepatitis: uncommon & often predated by chronic symptoms

■Chronic hepatitis: associated w/ variable physical signs & symptoms;

may be detected when patient is asymptomatic

■Advanced liver disease: liver failure (jaundice, hepatomegaly, pru-

ritus, ascites, encephalopathy) may be first presentation in many

patients

tests

Basic Blood Studies

■Early disease:

➣Moderately increased AST and ALT (range, 200–1000U), bilirubin,

& alkaline phosphatase

➣Serology (important for classification of AIH):

Positive ANA (50%) & SMA (70%) in classic type 1 AIH

Positive anti-LKM1 seen in type 2 AIH; rare in U.S. patients;

subgroup of patients w/ anti-LKM1 may have antibodies to

HCV & GOR (usually Mediterranean men)

Positive antibodies to soluble liver antigen (anti-SLA ab) &

liver/pancreas (anti-LP): type 3 AIH

Gamma-globulin=1.5×upper limit of normal & as high as

50–70 g/L

➣Advanced disease:

Increased serum bilirubin and INR; decreased serum albumin

Liver Biopsy

■Performed prior to treatment to assess severity of liver disease &

differentiate between alternative liver diseases

■Early disease: periportal/lobular hepatitis; plasma cell infiltration

■Moderate or advanced disease: fibrosis, cirrhosis

Imaging

■Abdominal US or CT: nonspecific/nondiagnostic:

➣Early disease: often normal

➣Advanced disease: small shrunken liver, venous collaterals sug-

gestive of portal hypertension

differential diagnosis

■PBC