Chronic Kidney Disease

Question 1

What are some factors which can affect the eGFR result?

Answer 1

• Pregnancy
• Muscle mass (e.g. amputees, bodybuilders)
• Eating red meat 12 hours prior to the sample being taken.

Question 2

What is the most commonly used formula for calculating eGFR called and what variables dose it use?

(HINT: It has superseded Cockroft-Gault)

Answer 2

Modification of Diet in Renal Disease (MDRD)

• Serum creatinine
• Age
• Gender
• Ethnicity

Question 3

Describe the different stages of CKD

Answer 3

Stage 1 - >90ml/min with some sign of kidney damage on other tests (U&Es, Proteinuria). If these tests are normal then there is no kidney disease.

Stage 2 - 60-90ml/min with some sign if kidney damage - but if tests are normal then no kidney disease.

Stage 3a - 45-59 ml/min - moderate

Stage 3b - 30-44ml/min - moderate

Stage 4 - 15-29ml/min - Severe.

Stage 5 - <15 ml/min - established renal failure.

Question 4

If someone has an eGFR of <15ml/min (established renal failure), what may be needed?

Answer 4

Dialysis or a kidney transplant.

Question 5

What are some common causes of CKD?

Answer 5

• Diabetic nephropathy
• Chronic glomerulonephritis
• Chronic pyelonephritis
• Hypertension
• Adult polycystic kidney disease

Question 6

What antihypertensives are useful for proteinuric renal disease (e.g. diabetic nephropathy)

Answer 6

ACE inhibitors are first line.

They tend to reduce filtration pressures and thus a small fall in glomerular filtration pressure(eGFR) can be expected.

Question 7

When prescribing an ACE inhibitor for proteinuric renal disease, what is an acceptable decrease in eGFR?

Answer 7

Up to 25%

Or a rise in creatinine of up to 30%.

Question 8

If the eGFR does reduce, what are you considering as an underlying cause?

Answer 8

Renovascular disease (e.g. renal artery stenosis)

Question 9

What is useful as an antihypertensive in CKD patients with a low eGFR & why?

Answer 9

Furosemide

It is particularly useful if GFR falls to below 45 ml/min. It has the added benefit of lowering serum potassium.

High doses are usually required.

Question 10

At what eGFR does anaemia usually occur in CKD?

Answer 10

< than 35 ml/min

It is usually a normochromic normocytic anaemia.

(Other causes of anaemia should be considered if the GFR is > 60 ml/min).

Question 11

What cardiac condition does anaemia in CKD usually predispose one to?

Answer 11

Left ventricular hypertrophy

Question 12

How does NICE suggest that anaemia in CKD is managed?

Answer 12

• Optimise iron status before starting erythropoiesis-stimulating agents (ESA).
• Some ESAs - Erythropoietin and Darbepoetin.
• Many patients, especially those on haemodialysis, will require IV iron.

Question 13

What is your target Hb level in CKD even with treatment like Iron, EPO or dialysis?

Answer 13

The 2011 NICE guidelines suggest a target haemoglobin of 10 - 12 g/dl

Question 14

What is the most common cause of death in haemodialysis patients?

Answer 14

Ischaemic heart disease

Question 15

How many antihypertensives are usually required to treat hypertension in CKD patients?

Answer 15

Usually more than two

Question 16

Which antihypertensives are first line & why?

Answer 16

Ace-Inhibitors