Autoimmune Hepatitis

Question 1

Autoimunne Hepatitis: What is it?

Answer 1

Autoimmune hepatitis= chronic inflammation of the liver due to genetic and environmental factors. It is rare.

Question 2

Autoimunne Hepatitis: Symptoms

Answer 2

• asymptomatic
• abdominal pain
• nausea and vomiting
• Jaundice
• fevr, fatigue, myalgia, malaise
• anorexia
• amenorrhea
• Features of cirrhosis including ascites, variceal bleeding etc.

Question 3

Autoimunne Hepatitis: Investigations

Answer 3

hightransaminases(ALT and AST) and minimal change in ALP levels (a “hepatitic” picture). Raisedimmunoglobulin G (IgG) levelsare an important finding.

Autoantibodiesintype 1 autoimmune hepatitisare:
- Anti-nuclear antibodies (ANA)
- Anti-smooth muscle antibodies (anti-actin)
- Anti-soluble liver antigen (anti-SLA/LP)

Autoantibodiesintype 2 autoimmune hepatitisare:
- Anti-liver kidney microsomes-1 (anti-LKM1)
- Anti-liver cytosol antigen type 1 (anti-LC1)

Liver biopsyforms part of the diagnosis. Key histology findings areinterface hepatitisandplasma cell infiltration.
- nterface hepatitis - Inflammation of the hepatocytes at the junction of the portal tract and the hepatic parenchyma
- Periportal lymphocytic inflammation
- Hepatocyte swelling
- Necrosis

Question 4

: Management

Answer 4

Treatmentis withhigh-dose steroids(e.g.,prednisolone). Other immunosuppressants are also used, particularlyazathioprine. Immunosuppressant treatment is usually successful at inducing remission (controlling the disease).

Liver transplantmay be required inend-stage liver disease. Autoimmune hepatitis can reoccur in the new liver.

Vaccination against HepA and B

Question 5

Hepatitis: Complications

Answer 5

Patients who are diagnosed with AIH will need regular follow up and monitoring of disease progression. Most patients with AIH will have a degree of fibrosis within the liver and will be at risk of progression to cirrhosis. Cirrhosis, in turn, can lead to the development of:
- Ascites
- Spontaneous bacterial peritonitis
- Haemorrhages (e.g. due to variceal bleeding)
- Hepatic encephalopathy
- Hepatocellular carcinoma

Patients can also suffer from iatrogenic complications related to steroid treatment, including osteoporosis, diabetes, hypertension, and opportunistic infections.

Question 6

AIM: Differentials

Answer 6

Some differential diagnoses include:

• Alcoholic liver disease(ALD). Clinical presentation can often be very similar, with similarly high levels of aminotransferases. However, in ALD, patients will have a strong history of alcohol abuse, there will not be any evidence of autoantibodies, and histological signs will be different.
• Non-alcoholic fatty liver disease(NAFLD). It can be difficult to distinguish between NAFLD and AIH as neither has laboratory tests or clinical features that are pathognomonic. However, the presence of autoantibodies will strongly suggest AIH over NAFLD as a diagnosis.
• ChronichepatitisC infection. Clinical presentation may be similar, and there may likewise be an elevation of LFTs and rarely patients may also have raised autoimmune antibodies. However, the diagnosis of hepatitis C can be excluded with a viral hepatology screen. On histology, hepatitis C classically features ground-glass hepatocytes which will not be present in AIH.