Chronic kidney disease

Question 1

Stages of chronic kidney disease can be classified according to the international CKD classification system which groups according to the eGFR into 5 stages:

What is the eGFR of each stage

Answer 1

Stage 5 (advanced) <15
Stage 4 (severely impaired) 15-29
Stage 3 (moderately impaired) 30-59
Stage 2 (mild reduction in GFR) 60-89
Stage 1 (normal/high GFR) >90

Question 2

Kidney excretory function is measured by estimating eGFR from serum creatinine levels

What is kidney filtration function be measured by (if normal filtration means no blood or protein should be found in urine) (2)

Answer 2

Urine dipstick

Protein creatinine ratio

Question 3

Define chronic kidney disease

Answer 3

Proteinuria or haematuria, and/or a reduction in the EGFR <60, for >3 months

Question 4

Relationship between plasma creatinine and GFR

Answer 4

Plasma creatinine unaffected until renal function <60%

Question 5

Causes/risk factors of chronic kidney disease (4)

Answer 5

DM
Hypertension

Less common:
Glomerulonephritis
Genetic disorders, e.g. polycystic kidney disease

Question 6

State the symptoms and signs of uraemia, i.e. high serum urea (major symptom of renal failure) (7)

Answer 6

Nausea.
Vomiting.
Fatigue.
Anorexia.
Weight loss.
Muscle cramps - legs
Pruritus - in very advanced kidney failure

Question 7

Clinical approach to managing someone with CKD

Answer 7

Detect underlying cause
Slow the rate of renal decline
Assess complications related to reduced GFR (prevent or treat)
Prepare for renal replacement therapy, i.e. dialysis or transplant

Question 8

Symptoms (5) /signs (3) of later stage chronic kidney disease

Answer 8

Symptoms

• fatigue
• anorexia
• nausea/vomiting
• pruritus
• dyspnoea

Signs

• oliguria (reduced urine output)
• peripheral oedema
• anaemia –> pallor

Question 9

In early stages of CKD, often patients are…

Answer 9

asymptomatic

Question 10

What ethnicity is at higher risk of CKD + what gender

Answer 10

Black/hispanic

Male

Question 11

Questions to ask in history to detect underlying cause of CKD

Answer 11

Previous history of renal disease
Family history of renal disease
Existing diseases, any autoimmune diseases
Long term medication
Symptoms/signs of uraemia

Question 12

Biochemical (3) and physiological (1) abnormalities of CKD

Answer 12

Biochemical

• Haematuria
• Proteinuria
• elevated serum creatinine

Physiological
-kidneys could be small/enlarged

Question 13

Initial investigations of CKD (7)

+ later investigation (1)

Answer 13

Serum creatinine
U+Es
FBC - may have anaemia
Urinalysis - dipstick, microscopy, culture
Urine protein: creatinine ratio
Estimation of GFR (eGFR)
Renal ultrasound

Renal biopsy

Question 14

In CKD, urine protein: creatinine ratio is…

Answer 14

protein > creatinine

Question 15

What test can be used to quantify protein in urine

Answer 15

Protein creatinine ratio

Question 16

Most important thing to do when CKD has been diagnosed is to slow the rate of renal decline if can do

What are the principles of the management of this (4)

Answer 16

BP control + proteinuria control
-with ACEI/ARB

Statin

Treat underlying cause, e.g. DM

Question 17

Complications related to reduced GFR (5)

Answer 17

Anaemia - due to deficiency of erythropoietin production

Bone disease - due to elevated PTH as a result of phosphate retention and hypo Ca2+

CV disease

Metabolic acidosis

Hyperkalaemia - inability to excrete K+ from diet

Question 18

Failure to maintain fluid balance in those with advanced stages 4 and 5 CKD is an indication to start

Answer 18

renal replacement therapy - dialysis or transplant

Question 19

Pruritus only starts appearing in what stage of CKD

Answer 19

advanced stage 5

Question 20

Treatment of metabolic acidosis (complication of CKD due to reduced eGFR)

Answer 20

oral sodium bicarbonate

Question 21

Treatment of bone disease (complication of CKD due to reduced eGFR resulting in phosphate retention and elevated PTH) (2)

Answer 21

Restrict calcium and phosphate from diet

Phosphate binding drugs - bind to phosphate to normalise serum phosphate levels

Question 22

Treatment of anaemia (long term complication of CKD)

Answer 22

Erythropoetin stimulating agent

Question 23

Types of dialysis

Answer 23

Peritoneal

Haemo