Chronic Kidney Disease Flashcards
definition of chronic kidney disease?
abnormal kidney function and/or structure (includes genetic/inherited)
requires a minimum of two positive samples at least 90 days apart
chronic kidney disease often co-exists with other diseases?
cardiovascular disease
diabetes
best indication of kidney function? what does this include?
eGFR based on - creatinine level - age - sex - race
5 stages of CKD based on eGFR?
1 = >90 2 = 60-89 3a = 45-59 3b = 30-44 4 = 15-29 5 = <15
stages of CKD based on description?
1 = normal function but urine findings/structural abnormalities/genetic trait point to kidney disease 2 = mildly reduced function but findings point to kidney disease 3 = moderately reduced kidney function 4 = severely reduced kidney function 5 = established renal failure
chroni kidney disease epidemiology collaboration (CKD EPI)?
equation to estimate GFR creatinine
only given as >60, no specific value if GFR more than 60
categories of ACR (albumin:creatinine ratio)?
A1 = ACR <3 A2 = ACR 3-30 A3 = >30
why is albumin used?
leaks out of the glomerulus when kidney function is reduced
how are eGFR and ACR used?
stage of CKD and category of ACR used to determine severity and requirement for follow up
how does acute kidney injury relate to CKD?
increased risk of CKD (nephrons can be damaged/lost)
therefore need monitoring for development/progression of CS for at least 2-3 years after acute kidney injury (even if serum creatinine has returned to baseline)
what is eGFRcystatinC?
test used at initial diagnosis to confirm or rule out CKD in people with eGFRcreatinine of 45-59 but no other marker of CKD (no proteinuria etc)
- > 60 = not CKD
- used as diagnosis of CKD can affect life insurance etc
definition of accelerated progression of CKD?
sustained decrease in GFR of 25% or more and a change in GFR category within 12 months
or
sustained decrease in GFR of 15ml/min/1.73m2 per year
risk factors for CKD progression?
cardiovascular disease proteinuria acute kidney injury hypertension diabetes smoking African, African-Caribbean or Asian family origin chronic NSAID use untreated urinary outflow tract obstruction
indications for referral for specialist assessment of kidney function?
GFR <30
ACR 70 or more (unless due to diabetes and already being treated)
ACR 30 or more with haematuria
sustained decrease in GFR of 25% or more and a change in GFR category
sustained decrease in GFR of 15ml/min or more within 12 months
hypertension which is poorly controlled despite use of 4 antihypertensive drugs
known or suspected rare or genetic causes of CKD
suspected renal artery stenosis
blood pressure control in CKD?
target BP in CKD = 120-139 systolic, diastolic <90
target BP in people with CKD AND diabetes and also people with ACR >69 = <130 systolic and diastolic <80
introduction of RAAS inhibitor medications (antihypertensives) are expected to have which effects which are considered normal?
GFR decrease up to 25% at most
increase in serum creatinine of at most 30%
any more than this then need to modify dose of drug
what drug is given first line for primary/secondary prevention of CVD in people with CKD?
atorvastatin
- increase dose if more than 40% reduction in non-HDL cholesterol is not achieved and eGFR is 30ml/min
3 main causes of CKD?
diabetes
hypertension
glomerulonephritis
examples of primary CKD?
membranous
IgA
primary FSGS
examples of secondary CKD?
diabetes lupus FSGS due to HIV heroin obesity
causes of vascular CKD?
Renal artery stenosis ischaemic/hypertensive nephrosclerosis microengiopathic (e.g haemolytic uraemic syndrome, TTP, pre-eclampsia) small vessel vasculitis - GPA - MPA - EGPA
causes of tubulointerstitial CKD?
acute interstitial nephritis tubulointerstitial nephritis autosomal dominant polycystic kidney disease reflux nephropathy infections etc
post renal causes of CKD?
obstruction
- calculi
- prostate
- bladder (malignancy, wall thickening etc)
clinical signs of CKD?
anaemia signs of weight loss advanced uraemia - lemon yellow skin tinge (not jaundice) - uraemic frost (smell of urea on skin) twitching - encephalopathic flap - confusion - pericardial rub/effusion (emergency) - kussmaul breathing
CKD may cause what ABG result?
metabolic acidosis
uraemic symptoms of CKD?
nausea and vomiting anorexia/weight loss fatigue itch altered taste restless legs muscle twitching concentration problems confusion
anaemia symptoms?
fatigue
muscle weakness
pain in CKD?
bony
neuropathic
ischaemic
visceral
renal consequences of CKD?
local - pain/haemorrhage/infection urinary - haematuria/proteinuria impaired salt and water handling hypertension electrolyte abnormalities acid-base disturbance
extra renal consequences of CKD?
cardiovascular disease
mineral and bone disease (CKD-MBD)
anaemia
nutrition
4 paths of renal replacement therapy (RRT) in end stage renal disease (ESRD)?
haemodialysis
peritoneal dialysis
transplantation
conservative management
CV risk in CKD?
10-20X higher risk of CVD death
risk starts when eGFR drops below 50
risk increases with microalbuminuria, even if eGFR is normal
CV risk modification in CKD?
general (diet, smoking etc)
control hypertension
prophylaxis (lipid lowering therapy, aspirin)
risk of aspirin in CKD?
risk of bleeding complications for patients on multiple anti-thrombotic agents
what is CKD-MBD?
chronic kidney disease - mineral and bone disorder causes changes in - calcium - phosphate - PTH - Vit D - FGF-23 presents with bone abnormalities, vascular calcification and lab abnormalities
consequences of CKD-MBD?
secondary/tertiary HPT vascular calcification bone pain fractures CV events lower QoL high morbidity and mortality
how is CKD-MBD managed via diet?
phosphate restriction (body cant excrete it well) salt reduction potassium restriction (if elevated >5.5) fluid restriction to 1-1.5L/day correct metabolic acidosis (sodium bicarbonate can cause a sodium load)
how can CKD-MBD be managed with medication?
alfacalcidol (active Vit D) phosphate binders - calcium based - aluminium - non calcium based calcimimetic (cinacalet)
risk of anaemia in CKD?
more common in eGFR <45
diabetic more at risk
target Hb = 100-120
how is anaemia investigated in CKD?
exclude other causes of anaemia
- B12 and folate deficiency
- check ferritin and iron stores, aiming for
- ferritin >100
- TSats >20%
- consider MDS/other haematological causes
how is renal anaemia managed?
iron therapy
if oral iron fails to replete store - refer for IV iron
- ferinject
- venofer
ESA (erythropoiesis stimulating agent) if Hb <100-110 despite no iron/haematinic deficiencies
