Renal - CKD Flashcards
What is CKD?
Chronic reduction in kidney function over 3 months
Permanent and progressive
What factors can cause CKD?
Diabetes
Hypertension
Medications (NSAIDs or lithium)
Glomerulonephritis
Polycystic kidney disease
How do patients with CKD present?
Most are asymptomatic
- Fatigue
- Pallor (anaemia)
- Foamy urine (proteinuria)
- Pruritis
- Oedema
- Peripheral neuropathy
- Nausea
What investigations are used for CKD?
eGFR
Estimated glomerular filtration rate
Based on serum creatinine, age and gender
Proteinuria
Urine albumin: creatinine ratio (ACR)
Haematuria
Urine dipstick or microscopy
Infection, malignancy, glomerulonephritis or kidney stones
Renal ultrasound
Obstructions
Polycystic kidney disease
BP
HbA1c
Lipid profile (hypercholesterolaemia)
What are the different stages of CKD?
G Stage
eGFR
1- Over 90
2- 60-89
3a- 45-59
3b- 30-44
4- 15-29
5- Under 15
A Stage
Albumin:creatinine ratio
1- Under 3mg/mmol
2- 3-30mg/mmol
3- Above 30mg/mmol
What is accelerated progression?
Sustained decline in eGFR within 1 year
What are the complications of CKD?
Anaemia
Renal bone disease
CVD
Peripheral neuropathy
End-stage kidney disease
Type 2 hyperparathyroidism
Dialysis-related complications
What is the kidney failure risk equation used for?
5-year risk of kidney failure requiring dialysis
What does NICE recommend for renal referral?
- eGFR less than 30
- Urine ACR more than 70mg/mmol
- Accelerated progression
- 5-year risk over 5%
- Uncontrolled hypertension despite 4 or more anti-hypertensives
How are underlying causes managed in CKD?
- Optimise diabetic control
- Optimise hypertension control
- Reduce or avoid nephrotoxic drugs
- Treating glomerulonephritis
What is the blood pressure target in patients under 80 with CKD?
130/80
What medications help slow CKD progression?
ACEi or ARBs
SGLT-2 inhibitors (dapagliflozin)
How can complications of CKD risk be reduced?
Exercise
Avoid smoking
Atorvastatin 20mg for primary prevention of CVD - all patients with CKD
How are the following complications managed?
Metabolic acidosis
Anaemia
Renal bone disease
Metabolic acidosis
IV NaCl 0.9% first-line
IV Sodium bicarbonate second-line
Anaemia
Iron and EPO
Renal bone disease
Vitamin D
Low phosphate diet
Phosphate binders
How is end-stage renal disease managed?
Special dietary advice
Dialysis
Renal transplant
When are ACEi offered?
Diabetes + ACR above 3mg/mmol
Hypertension + ACR over 30mg/mmol
All patients with ACR over 70mg/mmol
Why does serum potassium need close monitoring in CKD?
CKD and ACEi can cause hyperkalaemia
When are SGLT-2 inhibitors (Dapagliflozin) offered?
Diabetes + urine ACR above 30mg/mmol
Considered for
Diabetes + urine ACR 3-30mg/mmol
Non diabetics with ACR of 22.6mg/mmol
Why do patients with CKD get anaemia?
Kidneys produce EPO
CKD causes reduced EPO and a drop in RBCs causing normocytic anaemia and normochromic
Treat with EPO agents recombinant human EPO
Iron deficiency is treated first, IV iron given particularly in dialysis patients
Why do blood transfusions increase the risk of future transplant rejection?
Allosensitisation
Sensitises immune system when blood transfusions are given
What is renal bone disease also known as?
Chronic kidney disease-mineral and bone disorder
CKD-MBD
What does renal bone disease involve?
High serum phosphate
Low vitamin D activity
Low serum calcium
Osteoporosis can also exist alongside (treat with bisphosphonates)
Why do you get high serum phosphate in renal bone disease?
Reduced phosphate excretion by diseased kidneys
Why is there low vitamin D activity in renal bone disease?
Kidneys metabolise vitamin D into its active form
Diseased kidneys do not produce as much active vitamin D thus reducing vitamin D activity
Vitamin D also has a large role in promoting calcium absorption in the intestines, therefore low serum calcium too
Why does CKD cause secondary hyperparathyroidism?
Parathyroid glands release more PTH in response to low serum calcium and high serum phosphate
Why can renal bone disease lead to osteomalacia?
Increased turnover of bones due inadequate calcium supply
Why does osteosclerosis occur in renal bone disease?
Osteoblasts increase their activity due to decreased mineral density
This creates new tissue in the bone, this new bone is not properly mineralised due to low calcium levels
What is a Rugger jersey spine?
Characteristic renal bone disease X-ray finding
Sclerosis of both ends of each vertebral body and osteomalacia in the centre
How is renal bone disease managed?
Low phosphate diet
Phosphate binders
Active vitamin D (calcitriol and alfacalcidol)
Ensuring adequate calcium intake
