CKD

Question 1

CKD definition

Answer 1

Abnormal kidney function/structure >3mths with health implications

Question 2

CKD classifications

Answer 2

GFR:
G1 >90
G2 60-89
G3a 45-59
G3b 30-44
G4 15-29
G5 <15

Albuminuria:
A1 Albumin excretion <30, A:CR <3
A2 30-300mg/24h, 3-30mg/mmol
A3 >300mg/24h, >30mg/mmol

Also classified by underlying pathology

Question 3

Most common causes of CKD

Answer 3

Diabetes
Glomerulonephritis
HT/renovascular disease

Question 4

CKD prognosis

Answer 4

Higher all-cause, CV, kidney disease and AKI mortalities with CKD
Pt with CKD much more likely to die from CVD than need RRT

Question 5

CKD signs

Answer 5

Peripheral oedema
Anaemia signs
JVP raised
BP raised
Bone pain
Amenorrhoea

Question 6

CKD monitoring

Answer 6

GFR + albuminuria monitored annually at least
Every 6mths if high risk
Every 3-4mths if very high risk

Rapid progression is eGFR drop of >5/yr

Question 7

Nephrology referral indications in CKD

Answer 7

Stage G4/G5
A:CR >70mg/mmol unless due to DM and already treated
A:CR >30 with haematuria
Declining GFR
HT poorly controlled despite ≥4 anti-HT drugs
Known/suspected rare or genetic CKD cause

Question 8

Treatments to slow CKD progression

Answer 8

BP <140/90 or if DM/A:CR>70, <130/80

ACE-I/ARB (don’t combine anti-RAS drugs as hyperK+/ hypotension) if :
DM and A:CR>3
HT and A:CR>30
CKD and A:CR>70

Keep HBA1C<53mmol/L
<2g Na (<5g NaCL) per day

Question 9

Renal complications of CKD

Answer 9

Anaemia
Acidosis
Oedema
Bone-mineral disorders
Restless legs/cramps

Question 10

Treating renal complications of CKD - Anaemia

Answer 10

Treat deficiencies or EPO if Hb <110g/l (very rarely ESA treatment causes aplastic anaemia)

Question 11

Treating renal complications of CKD - Acidosis

Answer 11

NaHCO3 if eGFR<30 and bicarb <20

Not in fluid overload/HT

Question 12

Treating renal complications of CKD - Oedema

Answer 12

Fluid + sodium restriction

Loop -> loop + thiazide diuretic as severity increases

Question 13

Treating renal complications of CKD - Bone-mineral disorders

Answer 13

Dietary restriction + phosphate binders if phosphate >1.5 (1.7 in RRT)

Vit D supplements (cholecalciferol) if deficient
If inc PTH persists, use 1alpha-calcidol/calcitriol (active vit D analogues)

Paricalcitol suppresses PTH with less effect on enteric calcium absorption so less likely to cause inc Ca/P

Question 14

Treating renal complications of CKD - Restless legs/cramps

Answer 14

Exclude iron deficiency
Sleep hygiene advice
Severe cases give gabapentin/ pregabalin

Question 15

Treating renal complications of CKD with diet

Answer 15

Expert advice regarding protein intake
K+ if hyperkalaemic
Phosphate restriction e.g. dairy products

Question 16

Why does CKD increase CV risk

Answer 16

HT
Vascular stiffness
Inflammation
Oxidative stress
Abnormal endothelial function

Question 17

Treatments CV complications CKD

Answer 17

Low-dose aspirin (antiplatelet) unless bleeding risk
Atorvastatin 20mg for 1˚ + 2˚ prevention
Increased monitoring of GFR + K+ in heart failure
Consider GFR (<60) when interpreting troponin/BNP

Question 18

CKD preparation for RRT

Answer 18

Refer to nephrology >1yr before RRT needed, when risk of renal failure 10-20% within next year
List pts for deceased donor transplant 6mths before RRT starts, and try to find live donor

Question 19

Drugs affected in CKD

Answer 19

Renally excreted e.g. aminglycosides, penicillins, cephalosporins, heparin, lithium, opiates, digoxin
Cystatin c used for GFR in chemo dosing
Check RRT excretion rates of drugs if pt under RRT