Chronic Kidney Disease Flashcards
What is CKD?
Chronic reduction in kidney function as a result of damage to the kidneys, their vessels or pathology in lower urinary tract
Clinical definition of CKD?
Reduction in GFR to <60mL/min for at least 3 months
OR
Persistent proteinuria/haematuria
Causes of CKD?
- Diabetes
- HT
- Age-related decline
- Glomerulonephritis
- Polycystic kidney disease
- Medications eg NSAIDs, PPI, Ciclosproin, lithium
- SLE
Risk factors for CKD?
- Older
- HT
- Diabetes
- Smoking
- Use of kidney affecting meds
- Renal tract infections
Who gets CKD?
- African-Carribean
-South Asian
(probably because of prevalence of HT/T2DM)
-Acute kidney injury
-Hereditary diseases
Presentation of CKD?
Asymptomatic usually diagnosed on routine screening
Signs which suggest CKD?
- Pruritus
- Loss of appetite
- Nausea
- Oedema
- Muscle cramps
- Peripheral neuropathy
- Pallor
- HT
Complications arising from CKD?
- Anaemia
- Renal bone disease
- CVS
- Peripheral neuropathy
- Dialysis related problem
Investigation for CKD?
- U&E blood test (Find eGFR)
- Albumin: creatinine ratio to check for Proteinuria
- Urinalysis dip stick: check for haematuria
- Renal USS
- Urine microscopy: WBC, RBC
- Urine electrolytes
- FBC
- Biopsy if cause unclear
What is checked in a blood test for CKD?
- Urea, creatinine, eGFR
- Electrolytes
- Calcium
- Phosphate
- PTH
- FBC
- Complement components
2 aspects of staging CKD?
G score (based on eGFR) A score (based on albumin: creatinine ratio)
What is G score?
G1: eGFR= >90 G2: eGFR = 60-89 G3A: eGFR = 45-59 G3b: eGFR = 30-44 G4: eGFR 15-29 G5: eGFR <15
What is G5 also known as?
End stage renal failrue
What is A score?
A1: <3mg/mmol
A2: 3-30mg/mmol
A3: >30mg/mmol
What must a patient have for a diagnosis of CKD?
eGFR of <60
OR
Proteinuria
NICE suggest to refer to a specialist when?
- eGFR < 30
- ACR > 70mg/mmol
- ACR 30mg/mmol or more + haematuria
- Accelerated progression defined as a decrease in eGFR of 15 or 25% or 15ml/min in 1 year
- Uncontrolled HT despite 4 or more anti-HTs
- rare/genetic causes of CKD suspected or suspected renal artery stenosis
Reducing risk of complications with CKD?
- Exercise, diet, stop smoking, weight loss
- Special dietary advice about Phosphate, sodium, potassium and water intake
- Offer atorvastatin 20mg for primary prevention of CVD to people who have CKD
Treating complication: metabolic acidosis?
-Oral sodium bicarbonate
Treating complications: anaemia?
- Iron supplementation
- Erythropoietin
Treating complications: Renal bone disease?
Vit D
Treating HT?
1st line = ACEis However monitor serum K+ ONLY modify dose if - GFR decrease >25% or - serum creatinine increase>30% if less than these don't modify
What do healthy kidney cells produce?
Erythropoietin
What is erythropoietin?
Hormone which stimulates production of RBCs
What can anaemia be treated with?
Erythropoiesis stimulating agents such as exogenous erythropoietin
What is renal bone disease AKA?
Chronic kidney disease- Mineral and bone disorder (CKD MBD)
Features of renal bone disease?
- Osteomalacia
- Osteoporosis
- Osteosclerosis
X-ray changes in renal bone disease?
Rigger jersey spine
- Sclerosis of both ends of vertebra (denser white)
- Osteomalacia in centre of vertebra (less white)
Why does high serum phosphate happen in CKD?
Occurs due to reduced phosphate excretion
- Low active Vit D occurs because kidney is essential in metabolising Vit D to active form
- Vit D also regulates bone turnover
What can be caused by CKD?
- High serum phosphate
- Secondary hyperparathyroidism
- Osteomalacia
- Osteosclerosis
- Osteoporosis
Why does secondary hyperparathyroidism happen in CKD?
Parathyroid glands react to low serum calcium and high serum phosphate by excreting more PTH
- This leads to increased osteoclast activity
- Osteoclast activity leads to absorption of calcium from bone
What can be used to treat osteoporosis?
Bisphosphonates
what is the pattern of CKD?
frequently unrecognised
often co-exists with other conditions e.g. CVD, DM
moderate to severe CKD - increased risk of
- AKI
- falls
- fragility
- mortality
risk of developing CKD increases with age
aim of CKD treatment?
prevent/delay progression
reduce/ prevent complications
reduce risk of CVD
As people with AKI have an increased risk of CKD how should AKI patients be managed?
monitor people for development/ progression of CKD for 2-3 years after AKI even if serum Cr has returned to normal
when should atorvastatin be increased in patient with CKD to prevent CVD?
increase dose if
- non-HDL cholesterol is not decreased by >40%
and
- eGFR is > 30ml/min/1.73m2 or more
higher doses need to be agreed with renal specialist if eGFR <30ml/min/1.73m2
what is eGFRcystatinC used for?
at initial diagnosis - confirms/rules out CKD in people with eGFR creatinine 45-59 sustained for at least 90 days
no proteinuria (ACR <3mg/mol)/other marker of kidney disease
CKD if <60ml/min/1.73m2
what are the possible conditions/possible pathogenesis that lead to CKD?
diabetes mellitus hypertension glomerulonephritis - primary - membranous/IgA/FSGS - secondary - membranous/lupus/FSGS due to HIV/heroin/obesity vascular (macro and micro) - RAS - ischaemic/hypertensive nephrosclerosis - microangiopathic - HUS/TTP - SVV - GPA/MPA/EGPA tubulointerstitial - acute interstitial nephritis - tubulointerstitial nephritis - ADPKD - Reflux nephropathy post-renal (obstructive) - calculi: renal/ureteric/bladder - prostatic: BPH, cancer - bladder: malignancy, bladder wall thickening - urethral stricture
how does CKD present?
anaemia - conjunctival and palmar pallor, fatigue, muscle weakness signs of weight loss advanced uraemia uraemic symptoms - N&V - anorexia - weight loss - fatigue - itch - altered taste - restless legs - muscle twitching - difficulties concentrating - confusion pain - bony - neuropathic - ischaemic - visceral oedema - swelling - breathlessness
what is accelerated progression of CKD?
sustained decrease in GFR of 25% or more and change in GFR category within 12 months
or
sustained decrease in GFR of 15ml/min/1.73m2/year
risk factors for accelerated progression of CKD
CVD proteinuria AKI hypertension diabetes smoking African, African-Caribbean, Asian chronic NSAID use untreated urinary outflow tract obstruction
renal consequences of CKD
local - pain, stones, haemorrhage, infection
urinary - haematuria, proteinuria, nocturia, oliguria
impaired salt and water handling - pee at night, difficulty concentrating
hypertension
electrolyte abnormalites
acid-base disturbance
ESRD
extra renal consequences of CKD
cardiovascular disease - 10-20 fold higher risk of death than general population for ESRD. It starts early: eGFR <50ml/min. The risk is increased with microalbuminuria
mineral and bone disease
anaemia - less common if eGFR >45, diabetics are more at risk
how is the risk of CV disease managed?
- smoking cessation
- weight loss
- aerobic exercise
- limiting salt intake
control of hypertension
other prophylaxis - lipid-lowering therapy
- consider aspirin for secondary prevention (bleeding :( )
what causes the mineral and bone disease related to CKD?
different adaptive changes in - calcium - phosphate - PTH - Vitamin D - FG-23 seriously compromised homeostatic mechanisms bone abnormalities and vascular calcification and laboratory abnormalities
what are the consequences of the bone and mineral abnormalities associated with CKD?
secondary/ tertiary HPT vascular calcification bone pain fractures CV events lower QoL higher morbidity and mortality
how are bone and mineral abnormalities associated with CKD managed?
phosphate restriction also consider - salt reduction - potassium restriction (if persistentily >5.5 mmol/L) - fluid restriction: 1-1.5L/day - dietary restrictions also - DM/coeliac disease correct metabolic acidosis: NaHCO3 can result in Na overload medications alfacalcidol - active vitamin D phosphate binders - calcium based - aluminium - non-calcium based calcimimetic = cinacalcet
how is anaemia managed?
target Hb:100-12 g/L
- lower level acceptable if Hb fails to rise despite adequate iron replacement & epoetin therapy
investigation
- exclude other causes: B12/folate deficiency
- check ferritin & iron stores: ferritin >100, T Sats > 20%
- consider MDS/ other haematological causes
management
- ferinject - ferric carboxymaltose
- venofer - iron sucrose
- if oral fails - IV iron
