Chronic Kidney Disease Flashcards
Common causes of chronic kidney disease
diabetic nephropathy chronic glomerulonephritis chronic pyelonephritis hypertension adult polycystic kidney disease
Serum creatinine may not provide an accurate estimate of renal function due to
differences in muscle.
For this reason, formulas were developed to help estimate the glomerular filtration rate (estimated GFR or eGFR).
What formula is used to estimated gfr and what variables does it look at
Modification of Diet in Renal Disease (MDRD) equation, which uses the following variables: serum creatinine age gender ethnicity
What factors affect gfr result?
pregnancy
muscle mass (e.g. amputees, body-builders)
eating red meat 12 hours prior to the sample being taken
CKD may be classified according to
GFR
Describe the stages of CKD?
1 Greater than 90 ml/min, with some sign of kidney damage on other tests (if all the kidney tests* are normal, there is no CKD)
2 60-90 ml/min with some sign of kidney damage (if kidney tests* are normal, there is no CKD)
3a 45-59 ml/min, a moderate reduction in kidney function
3b 30-44 ml/min, a moderate reduction in kidney function
4 15-29 ml/min, a severe reduction in kidney function
5 Less than 15 ml/min, established kidney failure
dialysis or a kidney transplant may be needed at which stage of CKD?
5
Usually chronic kidney disease is asymptomatic and diagnosed on routine testing
true
Aims of CKD management?
Slow the progression of the disease
Reduce the risk of cardiovascular disease
Reduce the risk of complications
Treating complications
How do you reduce risk of complications in CKD?
Exercise, maintain a healthy weight and stop smoking
Special dietary advice about phosphate, sodium, potassium and water intake
Offer atorvastatin 20mg for primary prevention of cardiovascular disease
What is the A Score? What does it include?
The A score is based on the albumin:creatinine ratio:
A1 = < 3mg/mmol A2 = 3 – 30mg/mmol A3 = > 30mg/mmol
The patient does not have CKD if they have which scores?
score of A1 combined with G1 or G2. They need at least an eGFR of < 60 or proteinuria for a diagnosis of CKD.
Complications of CKD?
Anaemia Renal bone disease Cardiovascular disease Peripheral neuropathy Dialysis related problems
Investigations for CKD?
Estimated glomerular filtration rate (eGFR) can be checked using a U&E blood test. Two tests are required 3 months apart to confirm a diagnosis of chronic kidney disease.
Proteinuria can be checked using a urine albumin:creatinine ratio (ACR). A result of ≥ 3mg/mmol is significant.
Haematuria can be checked using a urine dipstick. A significant result is 1+ of blood. Haematuria should prompt investigation for malignancy (i.e. bladder cancer).
Renal ultrasound can be used to investigate patients with accelerated CKD, haematuria, family history of polycystic kidney disease or evidence of obstruction.
When should you refer to a specialist?
NICE suggest referral to a specialist when there is:
eGFR < 30
ACR ≥ 70 mg/mmol
Accelerated progression defined as a decrease in eGFR of 15 or 25% or 15 ml/min in 1 year
Uncontrolled hypertension despite ≥ 4 antihypertensives
Roughly outline how should you treat complications of CKD?
Oral sodium bicarbonate to treat metabolic acidosis
Iron supplementation and erythropoietin to treat anaemia
Vitamin D to treat renal bone disease
RRRT in end stage renal failure
The majority of patients with chronic kidney disease (CKD) will require more than two drugs to treat hypertension.
true
Which hypertension drugs are particularly helpful in proteinuric renal disease
ACE inhibitors
Which drugs reduce filtration pressure?
ACE inhibitors
these drugs tend to reduce filtration pressure a small fall in glomerular filtration pressure (GFR) and rise in creatinine can be expected
When using ACEi in hypertension NICE suggest that a decrease in eGFR of up to ?% or a rise in creatinine of up to ?% is acceptable
decrease in eGFR of up to 25% or a rise in creatinine of up to 30% is acceptable
A rise greater than this may indicate underlying renovascular disease.
When using ACEi in hypertension any rise in creatinine should prompt what
careful monitoring and exclusion of other causes (e.g. NSAIDs)
Other than ACEi, what other drug is useful in CKD?
Furosemide
Furosemide is useful as a anti-hypertensive in patients with CKD, particularly when
the GFR falls to below 45 ml/min
guidelines suggest a lower cut-off of less than 30 ml/min
What is a benefit of furosemide in hypertension and CKD?
lowering serum potassium
High doses of furosemide in hypertension and CKD are usually required
true
When should you consider stopping furosemide?
If the patient becomes at risk of dehydration (e.g. Gastroenteritis) then consideration should be given to temporarily stopping the drug
Patients with chronic kidney disease (CKD) may develop anaemia due to a variety of factors, the most significant of which is
Reduced erythropoietin levels
What kind of anaemia do you usually get in CKD?
normochromic normocytic anaemia
Anaemia in CKD predisposes to the development of
left ventricular hypertrophy
left ventricular hypertrophy is associated with a three fold increase in mortality in renal patients
true
normochromic normocytic anaemia and becomes apparent when the GFR is less than
35 ml/min
other causes (other than reduced erythropoietin levels) of anaemia should be considered if the GFR is > 60 ml/min
true
Causes of anaemia in renal failure?
Reduced erythropoietin levels - the most significant factor
Uraemia can lead to - reduced erythropoiesis due to toxic effects of uraemia on bone marrow, anorexia/nausea
reduced absorption of iron
Reduced red cell survival (especially in haemodialysis)
Blood loss due to capillary fragility and poor platelet function
Stress ulceration leading to chronic blood loss
NICE guidelines suggest a target haemoglobin of what in CKD
10 - 12 g/dl
In CKD Many patients, especially those on haemodialysis, will require IV iron
true
In anaemic CKD patients, what should be carried out before administering erythropoiesis-stimulating agents?
determination and optimisation of iron status
Examples of erythropoiesis-stimulating agents?
erythropoietin and darbepoetin
When should ESA’s be used? (CKD anaemia)
‘who are likely to benefit in terms of quality of life and physical function’
Proteinuria is an important marker of chronic kidney disease, especially for
diabetic nephropathy
NICE recommend using the albumin:creatinine ratio (ACR) in preference to the protein:creatinine ratio (PCR) when identifying patients with proteinuria as it has greater sensitivity
true
For quantification and monitoring of proteinuria, PCR can be used as an alternative, although ACR is recommended in diabetics.
