liver disease diagnosis and treatment

Question 1

what enzymes and proteins are measured in LFTs

Answer 1

aspartate transaminase (AST), alanine transaminase (ALT), gamma glutamyl transferase (GGT), alkaline phosphatase (ALP), bilirubin, albumin, prothrombin time, urea and ammonia

Question 2

what is the role of aspartate transaminase (AST) and its therapeutic range

Answer 2

plays a role in gluconeogenesis but not liver specific - 5-40 IU/L

Question 3

what is the role of alanine transaminase (ALT) and its therapeutic range

Answer 3

plays a role in gluconeogenesis but is more specific to the liver - 5-30IU/L

Question 4

what is the role of gamma glutamyl transferase (GGT) and its therapeutic range

Answer 4

Catalyses transfer of gamma glutamyl moiety of glutathione to an amino acid, peptide or water - 5-45IU/L, high in biliary obstruction

Question 5

what is the ratio of ALT:AST

Answer 5

> 2 - alcohol
<1 - other causes

Question 6

what is the role of alkaline phosphatase (ALP) and its therapeutic range

Answer 6

Removes phosphate groups from nucleotides, proteins and alkaloids - 20-100IU/L

Question 7

what is the role of bilirubin and its therapeutic range

Answer 7

• Unconjugated from red blood cell breakdown
• Conjugated suggests issue with liver
  jaundice at >35umol/L

Question 8

what is the role of albumin and its therapeutic range

Answer 8

plasma protein synthesised solely by the liver- 60-80g/dL

Question 9

what is prothrombin time

Answer 9

how long blood takes to clot, should be 10-15 secs

Question 10

what is the role of ammonia and its therapeutic range

Answer 10

increased in liver disease - 2.5-7.8mmol/L

Question 11

what effect does liver disease have on drug absorption

Answer 11

increased drug sensitivity
drug clearance
biotransformation
pharmacokinetics

Question 12

how does liver disease alter drug metabolism

Answer 12

plasma protein changes
hepatic extraction flow
biliary excretion
renal clearance

Question 13

what does it mean if a drug has a high extraction ratio

Answer 13

Clearance depends on hepatic blood flow

Question 14

which drugs have a high extraction ratio

Answer 14

morphine
propranolol
metoprolol
verapamil

Question 15

what does it mean if a drug has a low extraction ratio

Answer 15

clearance depends on metabolising capacity of the liver

Question 16

what drugs have a low extraction ratio

Answer 16

phenytoin
diazepam
warfarin
atenolol
prednisolone

Question 17

what are the minor symptoms of acute alcohol withdrawal

Answer 17

CNS hyperactivity
insomnia
tremors
anxiety
sweating
palpitations

Question 18

what are the more serious symptoms of acute alcohol withdrawal

Answer 18

seizures (12-48hrs)
alcoholic hallucinations
delirium tremens (48-96hrs)
fluid and electrolyte abnormalities

Question 19

how do you treat acute alcohol withdrawal

Answer 19

• chlordiazepoxide or oxazepam in severe disease/elderly
• IV fluids
• nutritional supplements

Question 20

what is cholestatic pruritis

Answer 20

Severe itchiness caused by deposition of excess bile salts under the skin

Question 21

how to treat cholestatic pruritis

Answer 21

underlying cause!
1. cholestyramine
2. non-sedating antihistamines
3. calamine/menthol/aqueous cream

Question 22

what is ascites

Answer 22

Activation of renin angiotensin system due to renal blood flow reduction causes secondary hyperaldosteronism = fluid retention in abdomen

Question 23

how to treat ascites

Answer 23

1. spironolactone
2. furosemide
   - rest and fluid restriction
   - 0.5-0.75kg reduction/day

Question 24

what is wernicke korsakoff syndrome

Answer 24

Neurological abnormality due to thiamine deficiency - normally due to malnutrition with alcoholism

Question 25

how to treat wernicke korsakoff syndrome

Answer 25

IV pabrinex tds for 3-5 days - anaphylaxis risk
oral thiamine at home for prophylaxis

Question 26

what is hepatic encephalopathy

Answer 26

neurological symptoms due to ammonia and nitrogenous waste products bypassing the liver and crossing the blood brain barrier

Question 27

how to treat hepatic encephalopathy

Answer 27

1. lactulose 30-50ml tds
2. rifaximin
3. phosphate enema

Question 28

what is portal hypertension

Answer 28

in severe liver disease there is a disordered anatomy and reduction of blood through the liver
Formation of collateral circulation to compensate and occurs in abdominal area

Question 29

how is portal hypertension treated

Answer 29

1. propranolol - low and slow
2. other vasocdilators

Question 30

what are bleeding oesophageal varices

Answer 30

• Haemorrhage under huge back pressure associated with portal hypertension

Question 31

how are oesophageal varices treated

Answer 31

• Vasoactive therapy - vasopressin
  
  • Vasoconstriction of blood vessels to reduce BP
  • Started ASAP
• Endoscope
  
  • Sclerotherapy - ethanolamine injected to cauterise/stop bleeds
  • Ligation/banding
  • Balloon tamponade
  • TIPS

Question 32

what causes clotting abnormalities in liver disease

Answer 32

• Liver not producing enough clotting factors
  ○ Prothrombin time >18secs

Question 33

how are clotting abnormalities treated

Answer 33

• Phytomenadione IV (vit K)
  May not work in severe cases