A 38-year-old woman comes to your outpatient clinic with complaints of fatigue and elevated serum liver tests since 8 months. Her lab results are: Bilirubin 9 ┬Ámol/L (ULN 17), Alkaline phosphatase 279 U/L (ULN 120), Gamma-GT 197 U/L (ULN 40), ASAT 116 U/L (ULN 40), ALAT 182 U/L (ULN 34). HBsAg and anti-HCV are negative. IgG 24.3 g/L (ULN 16), IgM 1.54 g/L (ULN 2.3), ANA positive (homogenous nuclear staining), anti-smooth muscle antibodies positive, anti-mitochondrial antibodies negative. Ultrasound of the liver: Liver size, surface and parenchyma without abnormalities, slender bile ducts, open arterial and venous vessels, normal portal vein flow, normal spleen size of max. 9 cm. MRCP: no abnormalities.

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