Chronic Kidney Disease

Question 1

What does chronic kidney disease describe?

Answer 1

Abnormal kidney and/or structure

Question 2

What are some features of chronic kidney disease?

Answer 2

Common, frequently goes unrecognised, often co-exists with other conditions (e.g diabetes), risk increases with age

Question 3

What is moderate/severe chronic kidney disease associated with?

Answer 3

Increased risk of acute kidney injury, falls, frailty and mortality

Question 4

How many samples are needed to define chronic kidney disease?

Answer 4

At least two samples taken at least 90 days apart

Question 5

What is the best way of defining chronic kidney disease?

Answer 5

eGFR = more accurate measure of renal function than creatine, units are mg/ml/1.73 metres squared

Question 6

What is eGFR based on?

Answer 6

Serum creatine level, age, sex and race

Question 7

What is used to estimate the GFR of creatine?

Answer 7

The CKD-EPI creatine equation

Question 8

What is stage G1 of CKD?

Answer 8

eGFR >90

Normal kidney function but urine findings/structural abnormalities/genetic trait point to kidney disease

Question 9

What is stage G2 of CKD?

Answer 9

eGFR of 60-89

Mildly reduced kidney function but urine findings/structural abnormalities/genetic trait point to kidney disease

Question 10

What is stage G3 of CKD?

Answer 10

Moderately reduced kidney function
3a = eGFR of 45-59
3b = eGFR of 30-44

Question 11

What is stage G4 of CKD?

Answer 11

eGFR of 15-29

Severely reduced kidney function

Question 12

What is stage G5 of CKD?

Answer 12

eGFR < 15

Established renal failure

Question 13

How can the albumin/creatine ratio be used to stage CKD?

Answer 13

A1 = ACR <3 mg/mmol
A2 = ACR of 3-30 mg/mmol
A3 = ACR >30 mg/mmol

Question 14

How long should patients who have suffered from an acute kidney injury be monitored for CKD?

Answer 14

At least 2-3 years after (even if serum creatine returns to baseline)

Question 15

What should be used to confirm CKD?

Answer 15

eGFRcystatinC

Question 16

When should you consider diagnosing CKD?

Answer 16

Patients with an eGFR creatine of 45-59 sustained for at least 90 days and no proteinuria (ACR <3 mg/mmol)

Question 17

What patients should you not diagnose CKD in?

Answer 17

eGFR creatine of 45-59
eGFRcystatinC >60
No other marker of kidney disease

Question 18

When should you offer testing for chronic kidney disease?

Answer 18

Diabetes, hypertension, acute kidney injury, CV disease, structural renal tract disease, recurrent renal calculi, prostatic hypertrophy, multi-system diseases that can involve the kidneys (e.g SLE), family history of end age CKD or hereditary kidney disease

Question 19

What indicates that chronic kidney disease is progressing?

Answer 19

Sustained decrease in GFR or 25% or more and a change in GFR category within 12 months OR sustained decrease in GFR of 15% per year

Question 20

What are the risk factors for chronic kidney disease progression?

Answer 20

CV disease, proteinuria, acute kidney injury, hypertension, diabetes, smoking, African/Afro-Caribbean/Asian, chronic use of NSAIDs

Question 21

When should you consider referring a patient?

Answer 21

GFR <30 with or without diabetes
ACR >= 70 mg/mmol (unless caused by diabetes)
ACR >= 30 mg/mmol together with haematuria
Evidence of progression
Hypertension that remains poorly controlled despite the use of 4 anti-hypertensive drugs
Known/suspected rare or genetic cause of CKD

Question 22

What is the target blood pressure for people with chronic kidney disease?

Answer 22

Systolic <140 mmHg (target is 120-139 mmHg)

Diastolic <90 mmHg

Question 23

What is the target blood pressure for patients with CKD and diabetes/ACR >= 70 mg/mmol?

Answer 23

Systolic <130 mmHg (target is 120-129 mmHg)

Diastolic < 80mmHg

Question 24

When should you not consider lowering the dose of RAAS inhibitors (e.g ACEi)?

Answer 24

If GFR decreases from pre-treatment baseline by less than 25% or the serum creatine increases from baseline by <30%

Question 25

What is the first choice drug for lowering lipids in patients with CKD?

Answer 25

Atorvastatin = 20mg for prevention of CVD

Question 26

When should you consider increasing the dose of atorvastatin?

Answer 26

If >40% reduction in HDL-cholesterol isn't achieved and eGFR is >=30

Question 27

What is the prevalence of CKD in England?

Answer 27

Stage 3-5 is 6% 1% of males and 2% of females aged 16-54 31% of males and 36% of females aged >=75

Question 28

What are some causes of CKD?

Answer 28

Diabetes, hypertension, calculi, ischaemic/hypertensive nephrosclerosis, cancer, GPA, EGPA, MPA

Question 29

What are the clinical signs of chronic kidney disease?

Answer 29

Anaemia = conjunctival and palmar pallor | Weight loss and signs of advanced uraemia

Question 30

What are the signs of advanced uraemia?

Answer 30

Lemon yellow, uraemic frost, twitching, confusion, encephalopathic flap, pericardial rub or effusion, metabolic acidosis

Question 31

What are the symptoms of chronic kidney disease?

Answer 31

``` Uraemic = nausea/vomiting, anorexia, fatigue, itch, altered taste, restless legs, difficulty concentrating Anaemia = fatigue, muscle weakness Pain = bony, neuropathic, ischaemic, visceral ```

Question 32

What are some renal consequences of chronic kidney disease?

Answer 32

Pain, haemorrhage, infection, haematuria, proteinuria, impaired salt and water handling, hypertension, electrolyte abnormalities, acid-base disturbance

Question 33

What are some extra-renal consequences of CKD?

Answer 33

CV disease, mineral and bone disease (CKD-MBD), anaemia, nutrition

Question 34

How may end stage renal disease (ESRD) be treated?

Answer 34

Renal replacement therapies (RRT) = haemodialysis, peritoneal dialysis, transplantation Conservative management

Question 35

When does CV disease associated with chronic kidney disease begin?

Answer 35

Starts from eGFR <50 ml/min | Risk increases with albuminuria (even if eGFR normal)

Question 36

How useful are CV risk calculators for predicting the risk of CKD patients developing CV disease?

Answer 36

Not very useful = significantly underestimate risk

Question 37

How can risk of developing CV disease be reduced?

Answer 37

General = smoking cessation, weight loss, aerobic exercise, limiting salt intake Control of hypertension and lipid lowering therapy Consider aspirin for secondary prevention

Question 38

What causes mineral and bone disease?

Answer 38

Adaptive changes in calcium, phosphate, PTH, vitamin D and FGF-23 = compromises homeostatic mechanism

Question 39

What are the consequences of mineral and bone disease?

Answer 39

Secondary/tertiary HPT, vascular calcification, bone pain, fractures, CV events, metabolic acidosis

Question 40

What dietary advice is given to patients with mineral and bone pain?

Answer 40

Phosphate restriction (if high), salt reduction, potassium reduction (if >5.5 mmol/l), fluid restriction to 1-1.5 l/day

Question 41

What are some medications given to treat mineral and bone disease?

Answer 41

Alfacalcidol = active vitamin D Phosphate binders = calcium based (Adcal/PhosLo), aluminium (Alucaps), non-calcium based (Lanthanum) Calcimimetic (Cinacalet)

Question 42

What patients with CKD are most at risk of developing anaemia?

Answer 42

Those with diabetes = less common in patients with eGFR >45

Question 43

What are the targets for patients with anaemia?

Answer 43

Hb = 100-120 g/l Ferritin >100 TSats >20%

Question 44

What must be ruled out in patients with anaemia?

Answer 44

B12 and folate deficiencies

Question 45

What ion therapy is used in patients with anaemia?

Answer 45

Ferinject (ferric carboxymaltose) or Venofer (iron sucrose)

Question 46

When is IV iron offered to patients with anaemia?

Answer 46

If oral iron fails to replete stores or isn't tolerated

Question 47

When are ESAs offered to patients with anaemia?

Answer 47

If Hb <100-110 g/dl despite no iron or haematinic deficiencies