Renal

Question 1

Name 3 factors that contribute to eGFR through the Cockcrof Gault equation.

Answer 1

1. Age
2. Weight
3. Serum Cr
4. Gender

Note: CKD-EPI is now the most widely used formula for eGFR which takes into account Gender, Age and Ethnicity

Question 2

What are the stages and cut-off for each stage of CKD?

Answer 2

Stage 1: eGFR >90
Stage 2: 60-89
Stage 3a: 45-59
Stage 3b: 30-44
Stage 4: 15-29
Stage 5 ESKD: <15

Note: eGFR 60 - 90+ is not CKD unless haematuria, structural or pathological abnormalities are present

Question 3

What marker is used to measure albuminuria and what are the ranges that define micro/ macro-albuminuria?

Answer 3

Urine ACR mg/mmol

Microalbuminuria:
- Male: 2.5 - 25
- Female: 3.5 - 35

Macroalbuminuria:
- Male: >25
- Female: >35

Question 4

What is first-line treatment for proteinuria in CKD?

Answer 4

RAAS blockade - ACEi or ARB as first-line

New evidence suggests that SGLT2i are now also beneficial in CKD irrespective of diabetic status (dapagliflozin TGA approved)

Question 5

What are BP targets in CKD with HTN ?

Answer 5

Aim BP <140/90 (without albuminuria)
Aim BP <130/80 (with albuminuria), ACEi/ARB

** SPRINT and ACCORD-BP studies **
** CLICK trial showed chlorthalidone also had BP/ uACR lowering efficacy **

Question 6

Name 3 common factors contributing to anaemia in CKD

Answer 6

1. EPO secreting cell dysfunction
2. Iron deficiency
3. Anaemia of chronic disease

Clinical mx: always ensure iron stores replenished before considering ESAs (EPO stimulating agents). Avoid pRBC (kidney transplant eligibility/ sensitization), target Hb 100-115g/L

ESAs are only used to target hb levels around 100.

Question 7

Describe the mechanism of acidosis in CKD

Answer 7

Lose ability to synthesize ammonia and lose ability to excrete hydrogen.

As a result ~20% of CKD Stage 4-5 patients have HCO3 <22mmol/L.

There is no target for HCO3 in late stage CKD. However, sodium b

Question 8

Describe the pathophysiology of hyperkalaemia in CKD and outline options for management.

Answer 8

1. Cessation of RAAS inhibition
2. Potassium Binders
   - Calcium/ Sodium polystyrene sulfonate (resonium)
   - Patiromer
   - Sodium Zirconium Cyclosilicate

Question 9

Calcium Phosphate Axis in CKD

What are the mechanisms of calcitriol?

Question 10

Calcium Phosphate Axis in CKD

What are the mechanisms of sevelamer?

Question 11

Calcium Phosphate Axis in CKD

What are the mechanisms of cinacalcet?