Autoimmune Hepatitis .

Autoimmune hepatitis is a chronic inflammatory liver disease caused by the immune system attacking the liver.
It is uncommon but important, because early treatment can prevent progression to cirrhosis and liver failure.

This guide focuses on when to suspect it, how to investigate it, and what juniors should actually do in practice.

What is autoimmune hepatitis?

Autoimmune hepatitis is:

Immune-mediated inflammation of the liver causing chronic hepatocellular injury.

Without treatment, it may progress to:

  • Fibrosis
  • Cirrhosis
  • Liver failure

Unlike many other liver diseases:

It is often very responsive to steroids.

How does it present?

Presentation varies a lot.

Most common:

  • Incidental abnormal LFTs
  • Mild fatigue

Sometimes:

  • Jaundice
  • RUQ discomfort
  • Arthralgia
  • Rash

Can present dramatically as:

  • Acute hepatitis
  • Acute liver failure
  • Decompensated cirrhosis

It can mimic almost any liver condition.

Common patient profile (think practically)

Typical features:

  • Young or middle-aged women
  • Other autoimmune diseases
    (thyroid disease, coeliac, T1DM, rheumatoid arthritis)

But:
Men and older adults can still get it — don’t rule it out based on demographics alone.

On the ward or clinic, always ask

Could this be autoimmune rather than alcohol or fatty liver?

Especially if:

  • No alcohol history
  • Not overweight
  • Persistent ALT elevation
  • Other autoimmune conditions
  • Negative viral screen

This is when AIH should come to mind.

Typical blood test pattern

Common findings:

  • Raised ALT/AST (often significantly elevated)
  • ALT > ALP
  • Raised IgG
  • Positive autoantibodies
  • Normal or mildly raised bilirubin

Pattern:

Hepatocellular injury (not cholestatic)

Key investigations (what juniors should actually order)

If AIH suspected:

Do:

  • Liver screen:
    • ANA
    • ASMA (smooth muscle)
    • LKM antibodies
    • IgG
  • Viral hepatitis screen
  • Ferritin/iron studies
  • Coeliac screen
  • Ultrasound liver

If suspicion remains:

  • Refer hepatology
  • Liver biopsy often needed for confirmation

Diagnosis is not made on antibodies alone.

First priority = exclude common causes first

Before labelling AIH, always exclude:

  • Alcohol-related disease
  • MASLD
  • Viral hepatitis
  • Drug-induced liver injury

Because these are much more common.

AIH is often a diagnosis of exclusion.

Management (specialist-led, but juniors should understand basics)

Treatment usually involves:

  • Steroids (prednisolone)
  • Often azathioprine for maintenance

Goal:

  • Suppress inflammation
  • Prevent fibrosis

Many patients need long-term treatment, sometimes lifelong.

Immediate management on the ward

If incidentally found abnormal LFTs:

  • Arrange proper liver screen
  • Document history carefully
  • Avoid hepatotoxic medications
  • Refer to hepatology

If presenting acutely with jaundice or coagulopathy:

  • Treat as acute liver disease
  • Early senior review

Do not start steroids yourself without specialist input.

When to escalate urgently

Escalate if:

  • Jaundice
  • INR rising
  • Encephalopathy
  • Suspected acute liver failure
  • Rapidly worsening LFTs
  • NEWS ≥5

These may represent:

  • Severe AIH flare
  • Acute liver failure

These patients need urgent specialist care.

Common mistakes juniors make

  • Assuming abnormal LFTs are always fatty liver
  • Not sending autoimmune screen
  • Starting steroids without specialist input
  • Ignoring raised IgG
  • Delayed referral
  • Missing AIH in older patients

Remember:
AIH is uncommon, but very treatable — missing it matters.

Take-home concept

Autoimmune hepatitis is a treatable cause of chronic liver disease.
Think of it when LFTs don’t fit alcohol or metabolic patterns, investigate properly, and refer early.