CKD

Question 1

Definition of CKD

Answer 1

Describes a chronic reduction in kidney function - tends to be permenant and progressive

Question 2

Causes of CKD

Answer 2

Diabetes

Hypertension

Age-related decline

Glomerulonephritis

Polycystic kidney disease

Medications such as NSAIDS,
proton pump inhibitors and lithium

Question 3

Risk factors for CKD

Answer 3

older age

Hypertension

Diabetes

Smoking

Use of medications that affect the kidneys

Question 4

Presentation of CKD

Answer 4

Usually asyptomatic and diagnosed on routine testing - number of signs/ symptoms that suggest chronic kidney disease:

• Pruritus (itching)
• Loss of appetite
• Nausea
• Oedema
• Muscle cramps
• Peripheral neuropathy
• Pallor
• Hypertension

Question 5

Investigations for CKD:

Answer 5

1. eGFR - can be checked using U&Es (2 tests 3 months apart for diagnosis)
2. Proteinuria - can be checked using urine albumin:creatinine ratio (ACR) (result of >=3mg/mmol is significant)
3. Haematuria - can be checked using urine dipstick. significant result of 1+ for blood.
4. Renal ultrasound - used to investigate ptx with accelerated CKD, haematuria, PCKD, or evidence of obstruction

Question 6

2 methods of staging CKD:

Answer 6

G score (using eGFR)

A score (using ACR)

Question 7

G- Score:

Answer 7

G1 = eGFR >90

G2 = eGFR 60-89

G3a = eGFR 45-59

G3b = eGFR 30-44

G4 = eGFR 15-29

G5 = eGFR <15 (known as “end-stage renal failure”)

Question 8

A score:

Answer 8

ACR

A1 = < 3mg/mmol
A2 = 3 – 30mg/mmol
A3 = > 30mg/mmol

Question 9

Diagnosis/ excluding CKD using the scores:

Answer 9

The patient does not have CKD if they have a score of A1 combined with G1 or G2. They need at least an eGFR of < 60 or proteinuria for a diagnosis of CKD.

Question 10

Complications of CKD:

Answer 10

Anaemia

Renal bone disorder

Cardiovascular disease

Peripheral neuropathy

Dialysis related problems

Question 11

When should you refer to specialist: (NICE)

Answer 11

eGFR <30

ACR >= 70mg/mmol

Accelerated progression - defined as disease in eGFR of 15 OR 25% OR 15ml/min in 1 year

Uncontrolled hypertension despite >=4 antihypertensives

Question 12

Aims of management in CKD:

Answer 12

• Slowing progression
• Reducing the risk of cardiovascular disease
• Reducing the risk of complications
• Treating the complications

Question 13

Management to slow the progression of CKD:

Answer 13

1. optimise diabetic control
2. optimise hypertensive control
3. treat glomerulonephritis

Question 14

Management to reduce risk of complications in CKD:

Answer 14

1. exercise, maintain a healthy weight and smoking cessation
2. Special dietary advice about:
   
   • Phosphate, sodium, potassium, and water intake
3. Offer atorvastatin 20mg for primary prevention of cardiovascular disease

Question 15

Treating metabolic acidosis in CKD:

Answer 15

oral sodium bicarbonate

Question 16

Treating anaemia in CKD:

Answer 16

Iron supplementation and erythropoietin

Question 17

Treating renal bone disease in CKD:

Answer 17

vitamin D supplementation

Question 18

Management options in end-stage renal failure:

Answer 18

Dialyisis

Transplant

Question 19

Criteria for offering ACE inhibitors for patients with CKD:

Answer 19

Meet one of these criteria:

• Diabetes plus ACR > 3mg/mmol
• Hypertension plus ACR > 30mg/mmol
• All patients with ACR > 70mg/mmol

Blood pressure targets:

• <140/90
• or < 130/80 if ACR > 70mg/mmol

Question 20

Monitoring serum potassium in CKD:

Answer 20

Needs to be monitored as both ACE inhibitors and CKD cause hyperkalaemia

Question 21

Anaemia of CKD:

Answer 21

Healthy kidney cells produce erythropoietin (EPO).
- Which stimulates RBC production

Damage to kidney cells in CKD cause decreased EPO - therefore a drop in RBC production

Question 22

Treatment of anaemia of CKD

Answer 22

Iron deficiency should be treated first if present (IV iron is usually preferred)

Exogenous erythropoietin

• Blood transfusions should be limited in transplant patients as they can sensitise the immune system - ‘allosensitisation’ so that transplanted organs are more likely to get rejected

Question 23

3 main features of renal bone disease:

Answer 23

Oseteomalacia - (softening of bones)

Osteoporosis (brittle bones)

Osteosclerosis ( hardening of bones)

Question 24

Why does osteomalacia take place in renal bone disease?

Answer 24

Occurs due to increased turnover of bones without adequate calcium supply

Question 25

Why does osteosclerosis take place in renal bone disease:

Answer 25

Occurs when osteoblasts respond by increasing their activity to match the osteoclasts by creating new tissue in the bone
- however, due to low calcium level this new tissue is not properly mineralised

Question 26

Osteoporosis in CKD

Answer 26

Can exist alongside renal bone disease because of compounding risk factors - such as use of steroids and age

Question 27

Pathophysiology of renal bone disease:

Answer 27

High serum phosphate occurs due to reduced phosphate excrestion

• low active vitamin D because the kidney is essential in metabolising vitamin D into active form

Active vitamin D is essential in calcium absorption from the intestines and kidneys
- vitain D also regulates bone turnover

2. SECONDARY HYPERPARATHYROIDISM:
   - occurs because parathyroid glands react to the low serum calcium and high serum phosphate by excreting more PTH.
   - This leads to increased osteoclast activity - which leads to the absorption of calcium from bone

Question 28

XR changes in renal bone disease

Answer 28

Spine xray shows sclerosis of both ends of the vertebra (denser white) and osteomalacia in the centre of the vertebra (less white). This is classically known as “rugger jersey” spine after the stripes found on a rugby shirt.

Question 29

Management of renal bone disease:

Answer 29

Active forms of vitamin D (alfacalcidol and calcitriol)
Low phosphate diet
Bisphosphonates can be used to treat osteoporosis