Liver Disease

Question 1

What are the main liver function tests and what are they associated with (detect)

Answer 1

AST, ALT: enzymes associated with hepatocyte damage

ALP: associated with cholangiocyte damage (i.e. Biliary disease)

Gamma GT: associated with cholangiocyte damage (i.e. Biliary disease)

Question 2

What are ALT & AST?

Which is more specific for liver disease

Answer 2

Alanine aminotransferase
Aspartate aminotransferase

Enzymes that help process proteins

ALT more specific to liver disease
AST found in other types of cell (e.g. Heart, intestine, musc)

Question 3

Why are ALP and Gamma GT used together in testing?

Answer 3

ALP elevated in large number of disorders affecting drainage of bile (e.g. Gallstones, tumour blocking common bile duct)

Also released from damages bone/placenta/intestine

So Gamma GT used as supplementary to ensure elevated ALP coming from liver/biliary tract

Question 4

What 2 other substances can be measured as a marker of liver function

Answer 4

Albumin

Bilirubin

Question 5

In what clinical condition(s) is albumin levels affected by

Answer 5

Reduced in advanced liver disease

Reduced more acutely in sepsis

Question 6

In what clinical condition(s) is bilirubin levels affected by

Answer 6

Raised in Liver / biliary tract diseases

Relatively non-specific

Question 7

What is Gamma GT

Answer 7

Gamma Glutamyl Transpeptidase

Often elevated in liver disorders (high senstivity, low specificity)
but not in diseases of bone/placenta/intestine

Also elevated in:
Obesity
Hyperlipidaemia
Diabetes
congestive cardiac failure
Diseases of kidney, pancreas, prostate

Question 8

ALT elevated:

Key questions to ask in history (acute, chronic)

Answer 8

Acute: age, sex, drugs, alcohol, travel, contacts, high risk behavious, autoimmunity, fever, cardiac probs, pregnancy

Chronic: age, sex, eyhnicity, BMI, lipids, diabetes, alcohol, travel, high risk behaviour, family history

Question 9

Main conditions that cause abnormal LFTs in asymptomatic patients

Answer 9

Diabetes / metabolic syndrome
Excessive alcohol
Chronic hepatitis B or C
Drugs

Question 10

ALT elevated:

Main tests to carry out in acute vs chronic hepatic illness

Answer 10

Acute: Hep A, B, C, E, EBV, CMV, TOXO, drugs screen, immunoglobulins, autoimmune profile, caeruloplasmin

Chronic: TFT, diabetic screen, Hep B, C, lipidsm immunoglobulins, autoimmune profile, ferritin, caeruloplasmin, alpha-1 antitrypsin, TTG

Question 11

Elevated ALP (cholestatic illness): 
Questions to ask in history (acute vs chronic illness)

Answer 11

Acute: age, sex, drugs/antibiotics, family hx - gallstones, abdo pain, reg flags, jaundice

Chronic: family hx, matabolic syndrome, recurrent fever, ith/lethargy, dry eyes/mouth, colitis, pain, SOB/resp symptoms, CCF

Question 12

Elevated ALP (cholestatic illness)
Causes (acute vs chronic illness)

Answer 12

Acute: CBD stones/gallstones, tumour, pancreatic patholgy, drugs (augmentin, flucoxacillin), infiltration, SOD

Chronic: PBC, sclerosin cholangitis, NASH (non-alcoholic steatohepatitis), alpha 1 antitrypsin, sarcoid, amyloid, HIV

Question 13

Investigation of cholestasis (if ALP raised)

Answer 13

Check Gamma GT - if isolated rise:
Stop alcohol, hepatotoxic drugs
Weight loss if BMI >25
Re-check LFTs

If ALP persistently raised: full liver screen
Dilated bile ducts: MRCP, ERCP
Non-dilated bile ducts: treat underlying disease, or liver biopsy if no diagnosis

Question 14

Differentials for isolated rise in bilirubin (>22)

Answer 14

Gilberts:
Unconjugated hyperbilirubinaemia
Harmless

Haemolysis:
Unconjugated hyperbilirubinaemia
Splenomagaly, anaemia, DCT, hepatoglobin, reticulocyte count
Pathological

Question 15

Causes of acute liver failure

Answer 15

Drugs:
Paracetamol, isoniazid, halothane, ecstasy

Viral:
Hep A, B, E

Wilsons disease

Autoimmune hepatitis

Reye’s syndrome

Cardiovascular:
Ischaemic hepatitis, Budd Chiari

Pregnancy (acute fatty liver)

Question 16

Signs of chronic liver disease

Answer 16

Often none
Spider naevi
Asterixis / flap
Relative hypotension (high total body Na: dont give saline)
Oedema
Jaundice
Enlarged liver
Splenomegaly
Gynecomastia (oestrogen not broken down)
Testicular atropphy
Impotence

Question 17

Signs of decompensation in cirrhosis

Answer 17

Ascites
Hepatic encephalopathy
Portal hypertension (variceal haemorrhage)

Question 18

Other Causes of ascites

Answer 18

Peritoneal disease
Heart failure
Diabetic nephropathy
Hypoalbuminaemia of other causes

Question 19

Management of bleeding varices

Answer 19

Prevention
Prophylactic antibiotics
Resuscitation (blood + platelets to stop bleeding)
Endoscopy: band ligation, sclerotherapy
Pharm: Terlipressin (vasoconstrictor)
Antibiotics: reduce infection and bacteria translocated to gut (also stops bleeding)
Balloon tamponade (temporary: if cant stop bleeding in endoscopy)
TIPS (portal shunt thru liver to reduce pressure in portal vein)

Question 20

What are the main functions of the liver

Answer 20

Nutrition/ metabolic:
Stores glycogen, releases glucose, absorbs fat/fat soluble vitamins, manufactures cholesterol

Makes bile salts
(Lipids derived from cholesterol, dissolves dietary fats)

Makes bilirubin
(Breakdown product of Hb)

Makes clotting factors

Immune functions 
(Kupfer cells engulf antigens - bacteria)

Detoxification:
Drug excretion (sometimes activation)
Alcohol breakdown

Manufactures proteins
(E.g. Albumin, binding proteins)