Prescribing in Liver and Renal Disease

Question 1

Outline the stages of CKD

Answer 1

Stage:
1 = GFR >90
2 = GFR 60-90
3 = GFR 30-60
4 = GFR 15-30
5 = GFR <15

Question 2

What’s the best indicator of liver synthetic function?

Answer 2

Prothrombin time

Question 3

What’s a good long-term indicator of liver function?

Answer 3

Abumin

Question 4

What is the Child Pugh scoring system used for?

Answer 4

Subjective system to predict death in non-transplanted patients. Can be done at bedside

Question 5

What is the MELD scoring system used for?

Answer 5

Objective calculation to predict death in cirrhotic patients. Can’t be done at bedside, as it requires calculations.

Question 6

Evaluate the use of serum creatinine as an indicator of kidney injury

Answer 6

Dependent on muscle mass and is only elevated once 50% of renal function is lost

Question 7

How is an eGFR calculated using the MDRD formula?

Answer 7

Uses age, creatinine levels, race (add 1.21 for african/afro-caribbean) and 0.742 for women and 1 for men.

Question 8

Evaluate the use of the MDRD formula to calculate eGFR

Answer 8

Doesn’t take into account weight, so is inaccurate at extremes of weight

Question 9

Name important drugs that can cause liver enzyme inhibition

Answer 9

– Antibiotics (erythromycin, ciprofloxacin, metronidazole, sulphonamides, chloramphenicol, isoniazid)
– Allopurinol
– Amiodarone
– Cimetidine
– Ethanol (acute)
– Ketoconazole
– Diltiazem, verapamil
– Omeprazole
– Sodium valproate
– Quinidine
– 5HT reuptake blockers
– Protease inhibitors

Question 10

Name important drugs that can cause liver enzyme induction

Answer 10

– Rifampicin
– Phenytoin
– Phenobarbitone, other barbiturates
– Carbamazepine
– Ethanol (chronic)
– Sulphonylureas
– Nevirapine
– St John’s wort

Question 11

Which drug, if prescribed in chronic liver disease, increases the risk of developing SBP?

Answer 11

PPIs

Question 12

Which drugs can cause drug-induced hepatitis (raised ALT/AST)

Answer 12

o Dose-dependent: paracetamol, alcohol, azathioprine

o Dose-independent: isoniazid, rifampicin, pyrazinamide, amiodarone, nifedipine

Question 13

Which drugs can cause drug-induced cholestasis (raised bilirubin/ALP)?

Answer 13

Chlorpromazine, chlorpropamide, erythromycin, nitrofurantoin, nifedipine, statins and co-amoxiclav

Question 14

After the age of 40, how does the GFR change every year?

Answer 14

Decreases each year by 0.8ml/min

Question 15

What drugs can increase the risk of developing renal stones/crystals?

Answer 15

Directly precipitate crystals: acyclovir, HIV protease inhibitors, methotrexate

Indirectly increase crystals developing: orlistat, allopurinol