CKD Flashcards
What is the definition of CKD?
reduced GFR and/or evidence of kidney damage- 2 measurements 3 months apart
How is GFR assessed?
estimated by creatinine clearance
Why does creatinine clearance over-estimate GFR
creatinine is secreted by tubules
What is creatinine produced?
muscle breakdown- muscular people produce more creatinine
How is creatinine adjusted?
corrected for women, black race and age by MDRD4 equation
What GFR is accurate for?
if GFR is less than 60ml/min
What must serum creatinine be in order for eGFR to be valid?
serum creatinine must be stable
How does eGFR affect actual GFR if muscle mass is low?
over-estimates
What is stage 1 CKD?
GFR >90ml/min with evidence of kidney damage
What is stage 2 CKD?
GFR 60-90ml/min with evidence of kidney damage
What must be present for a diagnosis of stage 1 or 2 CKD?
evidence of kidney damage
How are stages 3-5 CKD defined?
on GFR alone
What is evidence of kidney damage?
proteinuria; haematuria (in absence of LUT cause) or abnormal imaging
What is stage 3 CKD?
GFR 30-60
What is stage 4 CKD?
15-30
What is stage 5 CKD?
<15 GFR OR ON RENAL REPLACEMENT THERAPY
What risks does CKD increase?
CVS
Which patients are more likely to progress with CKD?
those with proteinuria; and younger patients (have longer to progress)
What are the common causes of CKD?
DM; HT; vascular disease; chronic glomerulonephritis; reflux nephropathy; polycystic kidneys
Why is the cause of CKD not always known?
many patients present late with small scarred kidneys which could be caused by lots of things
At what GFR do symptoms of decreased GFR appear?
<20ml/min
What are the symptoms of reduced GFR?
tiredness; poor appetite; itc and sleep disturbance
What is the most common type of polycystic kidneys?
autosomal dominant which presents in adulthood
What are the principles of managemnet of CKD?
slow progression; reduce CVS risk; treat complications of CKD and prepare for renal replacement therapy
What factors increase rate of progression of CKD?
proteinuria and BP; poor glycaemic control; smoking
What is the treatment used to slow progression?
ACEi and ARBs - also spironolactone
What do you need to be cautious about with ACEi and spironolactone?
cause intial fall in GFR and may cause hyperkalaemia
How is CVS risk reduced with CKD?
BP and proteinuria; stop smoking and statins
What complication should be checked for in patient with CKD?
anaemia- iron, B12 and folate
What is the treatment for IDA in CKD?
IV iron ; then epo by injection every week or fortnight
what is the target Hb in CKD?
10.5-12.5g/dl
Why might you get hyperparathyroidism in CKD?
impaired vitamin D hydroxylation leading to reduced clacium absorption and increased serum phosphate
What happens if secondary hyperparathyroidism is not treated?
the glands undergo hyperplasia and one gland may become autonomous leading to tertiary hyper-PTH
What are the consequences of tertiary hyper-PTH?
bone disease; vascular calcificaiton and heart valve calcification due to high clacium
What is the treatment for hyperparathyroidism?
alfacalcidol; reduced dietary phosphate intake and phosphate binders
What is alfacalcidol?
hydroxylated vitamin D which doesn’t need activated by the kdineys
Give examples of phsophate binders?
calcium carbonate; calcium acetate and sevelamer
What are the options for renal failure?
haemodialysis; peritoneal dialysis; transplantation and conservative mx
When do patients start receiving information about dialysis?
when GFR is about 20ml/min
What GFR do most patients begin dialysis?
8ml/min
What is needed for haemodialysis?
arterovenous fistula
When should patients be referred to vascular surgeons for AVF?
when GFR is around 15
How long does AVF need to mature?
6 weeks
How long does a catheter for peritoneal dialysis take until it can be used?
1-2 weeks
When can patients be listed for transplant?
within 6 months of dialysis
What patients tend to choose conservative mx?
older patients with mulitple co-morbidities
