Chronic Kidney Disease Flashcards
What does chronic kidney disease describe?
Abnormal kidney and/or structure
What are some features of chronic kidney disease?
Common, frequently goes unrecognised, often co-exists with other conditions (e.g diabetes), risk increases with age
What is moderate/severe chronic kidney disease associated with?
Increased risk of acute kidney injury, falls, frailty and mortality
How many samples are needed to define chronic kidney disease?
At least two samples taken at least 90 days apart
What is the best way of defining chronic kidney disease?
eGFR = more accurate measure of renal function than creatine, units are mg/ml/1.73 metres squared
What is eGFR based on?
Serum creatine level, age, sex and race
What is used to estimate the GFR of creatine?
The CKD-EPI creatine equation
What is stage G1 of CKD?
eGFR >90
Normal kidney function but urine findings/structural abnormalities/genetic trait point to kidney disease
What is stage G2 of CKD?
eGFR of 60-89
Mildly reduced kidney function but urine findings/structural abnormalities/genetic trait point to kidney disease
What is stage G3 of CKD?
Moderately reduced kidney function
3a = eGFR of 45-59
3b = eGFR of 30-44
What is stage G4 of CKD?
eGFR of 15-29
Severely reduced kidney function
What is stage G5 of CKD?
eGFR < 15
Established renal failure
How can the albumin/creatine ratio be used to stage CKD?
A1 = ACR <3 mg/mmol A2 = ACR of 3-30 mg/mmol A3 = ACR >30 mg/mmol
How long should patients who have suffered from an acute kidney injury be monitored for CKD?
At least 2-3 years after (even if serum creatine returns to baseline)
What should be used to confirm CKD?
eGFRcystatinC
When should you consider diagnosing CKD?
Patients with an eGFR creatine of 45-59 sustained for at least 90 days and no proteinuria (ACR <3 mg/mmol)
What patients should you not diagnose CKD in?
eGFR creatine of 45-59
eGFRcystatinC >60
No other marker of kidney disease
When should you offer testing for chronic kidney disease?
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
What indicates that chronic kidney disease is progressing?
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
What are the risk factors for chronic kidney disease progression?
CV disease, proteinuria, acute kidney injury, hypertension, diabetes, smoking, African/Afro-Caribbean/Asian, chronic use of NSAIDs
When should you consider referring a patient?
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
What is the target blood pressure for people with chronic kidney disease?
Systolic <140 mmHg (target is 120-139 mmHg)
Diastolic <90 mmHg
What is the target blood pressure for patients with CKD and diabetes/ACR >= 70 mg/mmol?
Systolic <130 mmHg (target is 120-129 mmHg)
Diastolic < 80mmHg
When should you not consider lowering the dose of RAAS inhibitors (e.g ACEi)?
If GFR decreases from pre-treatment baseline by less than 25% or the serum creatine increases from baseline by <30%
What is the first choice drug for lowering lipids in patients with CKD?
Atorvastatin = 20mg for prevention of CVD
When should you consider increasing the dose of atorvastatin?
If >40% reduction in HDL-cholesterol isn’t achieved and eGFR is >=30
What is the prevalence of CKD in England?
Stage 3-5 is 6%
1% of males and 2% of females aged 16-54
31% of males and 36% of females aged >=75
What are some causes of CKD?
Diabetes, hypertension, calculi, ischaemic/hypertensive nephrosclerosis, cancer, GPA, EGPA, MPA
What are the clinical signs of chronic kidney disease?
Anaemia = conjunctival and palmar pallor
Weight loss and signs of advanced uraemia
What are the signs of advanced uraemia?
Lemon yellow, uraemic frost, twitching, confusion, encephalopathic flap, pericardial rub or effusion, metabolic acidosis
What are the symptoms of chronic kidney disease?
Uraemic = nausea/vomiting, anorexia, fatigue, itch, altered taste, restless legs, difficulty concentrating Anaemia = fatigue, muscle weakness Pain = bony, neuropathic, ischaemic, visceral
What are some renal consequences of chronic kidney disease?
Pain, haemorrhage, infection, haematuria, proteinuria, impaired salt and water handling, hypertension, electrolyte abnormalities, acid-base disturbance
What are some extra-renal consequences of CKD?
CV disease, mineral and bone disease (CKD-MBD), anaemia, nutrition
How may end stage renal disease (ESRD) be treated?
Renal replacement therapies (RRT) = haemodialysis, peritoneal dialysis, transplantation
Conservative management
When does CV disease associated with chronic kidney disease begin?
Starts from eGFR <50 ml/min
Risk increases with albuminuria (even if eGFR normal)
How useful are CV risk calculators for predicting the risk of CKD patients developing CV disease?
Not very useful = significantly underestimate risk
How can risk of developing CV disease be reduced?
General = smoking cessation, weight loss, aerobic exercise, limiting salt intake
Control of hypertension and lipid lowering therapy
Consider aspirin for secondary prevention
What causes mineral and bone disease?
Adaptive changes in calcium, phosphate, PTH, vitamin D and FGF-23 = compromises homeostatic mechanism
What are the consequences of mineral and bone disease?
Secondary/tertiary HPT, vascular calcification, bone pain, fractures, CV events, metabolic acidosis
What dietary advice is given to patients with mineral and bone pain?
Phosphate restriction (if high), salt reduction, potassium reduction (if >5.5 mmol/l), fluid restriction to 1-1.5 l/day
What are some medications given to treat mineral and bone disease?
Alfacalcidol = active vitamin D
Phosphate binders = calcium based (Adcal/PhosLo), aluminium (Alucaps), non-calcium based (Lanthanum)
Calcimimetic (Cinacalet)
What patients with CKD are most at risk of developing anaemia?
Those with diabetes = less common in patients with eGFR >45
What are the targets for patients with anaemia?
Hb = 100-120 g/l
Ferritin >100
TSats >20%
What must be ruled out in patients with anaemia?
B12 and folate deficiencies
What ion therapy is used in patients with anaemia?
Ferinject (ferric carboxymaltose) or Venofer (iron sucrose)
When is IV iron offered to patients with anaemia?
If oral iron fails to replete stores or isn’t tolerated
When are ESAs offered to patients with anaemia?
If Hb <100-110 g/dl despite no iron or haematinic deficiencies
