CKD Flashcards
(31 cards)
CKD-EPI equation better for
eGFR <60
Not validated in pregnancy
eGFR is not appropriate for
AKI
Assumes steady state of creatinine generation and excretion. Better for CKD.
Can’t be used in AKI, children, preganncy, extremes of body weight (anorexia, body builders), patients taking creatinine supplements
Staging CKD combines
eGFR
Albuminuria
Preferred method of detecting proteinuria for screening in CKD
ACR
Easy to do and monitor with time
ACR vs PCR in CKD
When ACR is low, relationship is not clear
If ACR 3.5-34mg/ml, prefer ACR
People with CKD are most likely to die from
CV disease (MI + HF)
People with CKD are most likely to die from
CV disease (MI + HF)
Mortality risk is generally higher than risk of needing diagnosis/Tx
Definition of CKD
eGFR <60, structural abnormalities or persistent abnormalities for >3/12
Indications for kidney biopsy
AKI not recovering
Nephrotic range proteinuria (GN)
CKD with progressive/rapid loss of function
Acute nephritis - RPGN, acute GN (AKI, blood and protein in urine)
Assess treat response (after treatment for rejection for kidney transplant)
Assess prognosis
General management of CKD
WH nephrotoxics when unwell
Manage BP Reduce albuminuria - ACEi/ARBI - Spironolactone - Non-dihydropyridine CCB - SGLT2i
Manage complications
HTN
- As the CKD gets worse, requires more and more antihypertensives (add and don’t change)
Fluid overload
- Primarily sodium restriction
- Occasionally FR
- Thiazide +/- loop
Anaemia Nutritional advice - Dietary sodium <1500mg/day - DASH diet can reduce SBP by 11mmHg Acidosis Mineral disorders
MOA thiazide
Works in DCT
Disconnect between water and Na reabsorption = dilutional hyponatraemia
EPO in CKD
Benefits
Increase Hb and symptoms
Target Hb 100-120
No reduction in mortality or kidney function
Ferritin and TSAT target in CKD when using EPO
Serum ferritin 200-500
TSAT 20-30%
If anaemia doesn’t improve with EPO, what to think of?
Think of
Fe deficiency
Inflammation/infection
Also HIgh PTH B12, folate defiency Hypothyroid Marrow disorder Malignancy
Protein restriction in CKD
Any evidence?
Yes
Reduces loss of GFR
But malnutrition and increase mortality so its a fine balance. Need dietician advice.
How does hyperPTH cause anaemia?
HyperPTH –> change in bone marrow (more bone than marrow; fibrotic change) –> less red cells coming out of BM
CKD and acidosis
Pathophysiology
Consequences
Rx
Reduced GFR –> H+ retention –> reduced interstitial and intracellular pH –> inflammation – > interstitial fibrosis –> progression of CKD
Dimineralise bone
Reduced albumin synthesis
Chronic inflammation
Increased degradation of muscle
Rx
Diet - increase fruit and veg (metabolised to bicarb)
Sodium bicarbonate (aim >21)
- Risk of alkalosis and sodium loading
Correcting acidosis can slow down loss of function
CKD and mineral bone disorder
Pathophysiology
Rx
Reduced GFR –> retain phosphate –> PTH goes up –> phosphate comes down via urine loss + increased Ca2+ + decreased 1,25 dihydroxyitamin D
Strong epidemiological association between Ca, phos, PTH and mortality/CVD
Current guidelines suggest “normal” levels should be target
No guidance on how to achieve
No mortality evidence for phosphate binders
Do diabetes ESKD cause small or big kidneys?
Big
Otherwise most CKD is small kidneys
How do NSAIDs cause AKI?
Reduce afferent vasodilation
Increase efferent vasoconstriction
How do ACEI cause AKI?
Vasodilate afferent
Vasodilate efferent
Increase glomerular pressure
Effects of SGLT2i in CKD
Can initially reduce GFR (due to increasing sodium delivery to macular densa cells –> dilate afferent arteriole which is bad when there is high glomerular pressure)
But later on becomes renoprotective and reduced loss of GFR comperd to placebo
What eGFR can you not use SGLTi?
<30
What eGFR can you not use ACEI?
No hard rule
If GFR is below 15, be very cautious
And expect a reduction in GFR
