Renal: Chronic Kidney Disease Flashcards
What is the definition of chronic kidney disease?
Kidney damage that develops over a period of more than 3 months based on:
- Abnormal structure or function
- GFR less that 60
What are some causes of CKD?
Hypertension Diabetes Glomerulonephritis Renovascular Disease Polycystic kidney disease Amyloidosis SLE Renal tumour Alports syndrome NSAIDs
How does hypertension cause CKD?
Hypertension leads to a thickened lumen which leads to low perfusion of the kidneys and the nephrons. This causes ischaemia and inflammation which in turn causes destruction of the glomerulus (glomerulosclerosis). Over time this leads to CKD.
How does diabetes cause CKD?
Excess glucose in the blood binds to protein (non enzymatic glycation) and leads to arteriosclerosis (stiffening and narrowing) in the efferent arterioles of the kidney. This is an obstruction and puts pressure on flitration. This causes hypertrophy of the nephrons which is time causes CKD.
What happens to urea levels in CKD?
Urea is usually filtered out by the kidney into the urine. In CKD the ability of the kidneys to do this is impaired and so urea levels are higher in the blood.
What happens to pottasium levels in CKD.
Pottassium is usually filtered out by the kidney so in CKD the ability to do this is reduced leading to hyperkalemia.
What happens to calcium levels in CKD.
The kidneys activate vitamin D which causes calcium to be absorbed from the diet. In CKD this is impaired which leads to hypocalcaemia. As calcium levels get lower PTH is released which causes release of calcium from the bones. This can lead to renal osteodystophy.
How does CKD lead to hypertension?
Chronic golmerular hypoperfusion leads to increases renin release which then leads to hypertension!
What happens to the level of red blood cells in CKD?
The kidneys release EPO which causes the production of red blood cells. In CKD this is reduces which leads to anaemia.
What is a normal GFR?
Over 90ml/min
How do confirm a diagnosis of CKD?
Renal Ultrasound
Renal biopsy
What are the main complications of CKD?
Electrolyte abnormalities
Toxin build up
Weak bones
Hypertension
What are the stages of CKD and their corresponding GFR?
Stage 1: GFR over 90 with evidence of renal damage
Stage 2: GFR 60 - 89 with evidence of renal damage
Stage 3A: GFR 45 - 59
Stage 3B: GFR 30 - 44
Stage 4: GFR 15 - 29
Stage 5: GFR less than 15.
What is GFR?
The flow of filtered fluid through the kidney.
How do you treat CKD?
Treat reversible causes
Relieve any obstruction
Stop nephrotoxic drugs
Reduce cardiovascular risk
