AKT · Gastroenterology/Liverlow yield

Primary biliary cholangitis

Autoimmune destruction of intrahepatic bile ducts (anti-mitochondrial antibody)

Overview

A chronic autoimmune cholestatic liver disease - immune destruction of the small intrahepatic bile ducts leading to cholestasis, fibrosis and cirrhosis. Classically a middle-aged WOMAN with FATIGUE and ITCH (pruritus); cholestatic LFTs with a positive ANTI-MITOCHONDRIAL ANTIBODY (AMA). Treated with ursodeoxycholic acid. Associated with other autoimmune disease (Sjogren, thyroid).

Recognise

Middle-aged woman with FATIGUE and PRURITUS (often the earliest/most prominent), later jaundice
Cholestatic LFTs (raised ALP/GGT), raised IgM; xanthelasma, hepatomegaly; complications of cholestasis (osteoporosis, fat-soluble vitamin deficiency)
Associations: Sjogren, autoimmune thyroid, coeliac, scleroderma/CREST

Red flags

Progression to cirrhosis/portal hypertension; HCC risk
Severe pruritus impairing quality of life

Differentials & how to tell them apart

Primary sclerosing cholangitismen + UC, ANCA, BEADED ducts on MRCP, cholangiocarcinoma risk - PBC is women + AMA + small ducts

Autoimmune hepatitisHEPATITIC (ALT up) with ANA/anti-smooth-muscle, raised IgG - PBC is cholestatic with AMA/IgM

Extrahepatic obstructiondilated ducts/stone/tumour on imaging

Drug-induced cholestasisdrug history

Investigations

Cholestatic LFTs (ALP up), ANTI-MITOCHONDRIAL ANTIBODY (AMA - the hallmark, ~95%), raised IgM; USS/MRCP (exclude obstruction/PSC); biopsy if needed.

Management

Ursodeoxycholic acid (+ cholestyramine for itch)

1Confirm cholestatic LFTs + AMA (+/- biopsy). Ursodeoxycholic acid to slow progression; cholestyramine for pruritus; bone protection and fat-soluble vitamins.Gate: Itch in cholestasis is treated with cholestyramine (bile-acid sequestrant), NOT antihistamines; distinguish from PSC (men/UC/beaded ducts) and autoimmune hepatitis (hepatitic/ANA-IgG)
2Obeticholic acid for inadequate response; manage cirrhosis/portal hypertension; transplant for end-stage disease.

Ursodeoxycholic acid — first-line - slows progression; obeticholic acid second-line

Cholestyramine for pruritus — bile-acid sequestrant (antihistamines do not help cholestatic itch)

Fat-soluble vitamins + bone protection — manage cholestasis complications

Key points

Middle-aged woman + fatigue + itch + cholestatic LFTs + AMA + raised IgM = PBC, treat with ursodeoxycholic acid. Cholestyramine (not antihistamines) for the itch. PSC is the men/UC/beaded-duct counterpart.

Monitor & prognosis

LFTs; bone density; cirrhosis surveillance.

Slowed by ursodeoxycholic acid; cirrhosis if advanced.

Source: EASL; BSG