Autoimmune Hepatitis

Question 1

Define Autoimmune Hepatitis?

Answer 1

Chronic hepatitis of unknown aetiology, characterised by autoimmune features, hyperglobulinaemia and the presence of circulating autoantibodies

Question 2

What is the aetiology of Autoimmune Hepatitis?

Answer 2

In a genetically predisposed individual, an environmental agent may lead to hepatocyte expression of HLA antigens, which then become the focus of a principally T-cell mediated autoimmune attack
The raised titre or anti-nuclear antibodies (ANA), anti-smooth muscle antibodies (ASMA) and anti-liver/kidney microsomes (anti-LKM) are not thought to directly injure the liver
The chronic inflammatory changes are similar to those seen in chronic viral hepatitis with lymphoid infiltration of the portal tracts and hepatocyte necrosis, leading to fibrosis and, eventually, cirrhosis

Question 3

What are the two major forms of Autoimmune Hepatitis?

Answer 3

Type 1 (Classic)
Type 2

Question 4

What antibodies are involved in Type 1 Autoimmune Hepatitis?

Answer 4

ANA
ASMA
Anti-Actin antibodies (AAA)
Anti-soluble liver antigen (anti-SLA)

Question 5

What antibodies are involved in Type 2 Autoimmune Hepatitis?

Answer 5

Antibodies to liver/kidney microsomes (ALKM-1)

Antibodies to liver cytosol antigen (ALC-1)

Question 6

What is the epidemiology of Autoimmune Hepatitis?

Answer 6

Type 1: occurs in ALL age groups (but mainly young women)

Type 2: generally occurs in girls and young women

Question 7

What are most presentations of Autoimmune Hepatitis?

Answer 7

May be asymptomatic and discovered incidentally through abnormal LFT

Question 8

What is the insidious presentation of Autoimmune Hepatitis?

Answer 8

Malaise 
Fatigue 
Anorexia 
Weight Loss 
Nausea 
Jaundice 
Amenorrhoea
Epistaxis

Question 9

What is the presentation of Acute Hepatitis (25%)?

Answer 9

Fever 
Anorexia 
Jaundice 
Nausea/Vomiting/Diarrhoea 
RUQ pain
Some may present with serum sickness (e.g. arthralgia, polyarthritis, maculopapular rash)

Question 10

What aspects of the history do you focus on for Autoimmune Hepatitis?

Answer 10

Check for personal or family history of other autoimmune disease
A full history is important to rule out other causes of hepatits (e.g. viral, alcoholic)

Question 11

What are the signs of Autoimmune Hepatitis on physical examination?

Answer 11

Stigmata of chronic liver disease (e.g. spider naevi)
Ascites, oedema and hepatic encephalopathy are late features
Cushingoid features may be present before the administration of steroids

Question 12

What bloods would you do for Autoimmune Hepatitis?

Answer 12

LFTs
Clotting
FBC
Hypergammaglobulinaemia

Question 13

What specific LFTs would you do for Autoimmune Hepatitis?

Answer 13

High: AST, ALT, GGT, ALP and Bilirubin
Low: Albumin (in severe disease)

Question 14

What specific clotting test would you do for Autoimmune Hepatitis?

Answer 14

High PT (in severe disease)

Question 15

What do you look for specifically on the FBC for Autoimmune Hepatitis?

Answer 15

Low HB, Platelets and WCC (if hypersplenism from portal hypertension)

Question 16

What do you look for with regards to Hypergammaglobulinaemia about Autoimmune Hepatitis?

Answer 16

Presence of ANA, ASMA and Anti-LKM antibodies

Question 17

Why do we do a Liver Biopsy for Autoimmune Hepatitis?

Answer 17

Needed to establish diagnosis and check whether hepatitis or cirrhosis

Question 18

What tests do you do to rule out other causes of liver disease in Autoimmune Hepatitis?

Answer 18

Viral Serology
Urinary copper/caeruloplasmin
Ferritin and transferrin saturation
a1 antitrypsin
Anti-mitochondrial antibodies (PBC)

Question 19

What do you do to visualise structural lesions for Autoimmune Hepatitis?

Answer 19

US
CT
MRI
of Liver and abdomen

Question 20

Why do you do an ERCP for Autoimmune Hepatitis?

Answer 20

To rule out PSC