CKD + Hypertension Flashcards
(37 cards)
definition of chronic kidney disease
Abnormalities of kidney structure or function present for 3 months with implications for health. Evidence of Kidney disease include the following
1) albumin:creatinine ratio >3mg/mmol
2) eGFR <60ml/min/1.73²
3) evidence of kidney damage, 1 of the following
albuminuria/proteinuria
hematuria
electrolytes abnor due to tubular disorder
abnor detected by histology
structural abnor detected by imaging
hx of kidney transplant
what is the most common cause of CKD
DM
aetiology of CKD
DM - most common cause HTN - 2nd most common cause CV disease nephrotoxic drugs smoking polycystic kidney disease glomerular nephrotic and nephritic syndrome obstructive kidney disease atherosclerotic renal vascular disease neurogenic bladder BPH urinary diversion surgery urinary stone schistosomiasis - common in the middle east SLE?Vasculitis/myeloma amyloidosis
pathophysiology of CKD
- Kidney damage:
- Proteinuria
- Haematuria
- Anatomical abnormality
- Impaired GFR <60ml/min on at least 2 occasions
leads to
• Fibrosis of tubules, glomeruli and small blood vessels
• Progressive renal scarring
• Mostly irreversible
what are the 2 parameters used in staging CKD
GFR
albuminuria
what is the stages of CKD according to GFR criteria
stage 1 (normal or high) - > 90
Stage 2 (mildly decreased) - 60-90
stage 3a (mildly to moderately decreased) - 45 - 59
stage 3b (moderately to severely decreased) - 30 - 44
stage 4 (severely decreased) - 15-29
stage 5 (kidney failure) - < 15
what is the stages of CKD according to Albuminuria criteria
A1 (normal to mildly inc) - < 3
A2 (moderately inc) - 3-29
A3 (severely increased) - > 30
what are some urine related clinical features of CKD
- Nocturia
- Polyuria – initial stages due to inability to concentrate urine
- foamy urine – due to proteinuria
- hematuria
- GI symptoms: N+V, anorexia, peptic ulceration (due to urea levels toxic)
- Pruritus – due to build-up of toxic waste
what are some protein & haemoblobuline related clinical features of CKD
odema paller lethargy SOB epistaxis brusising - dec erythropoietin production
what are some extra-renal clinical features of CKD
hyperparathyroidism bone pain osteomalacia - dec Ca, inc PO4, incPTH peripheral paraesthesia and weakness autonomic dysfunction - postural hypotension and disturbed GI motility depressed cerebral function median tunerl compression amenorrhea erectile dysfunction infertility restless leg syndrome - due to ureamia build up
how do you diagnose a patient with CKD
serum creatinin - for eGFR
- if < 60, repeat wihtin 2 weeks
- if no deterioration, repeat within 3 months
- if still between 45- 59 & no proteinuira (ACR<3), confirm diagnsiss using eGFRcystatinC test
ARC ration & haematuria dip
- if ACR between 3 and 70, repeat within 3 months with an early mornign urine sample
- it initial ACR > 70, no need for further testing
- use urine dip strips to test for haematuria –> investigate further if strips shown 1+ or more blood
who would need a renal USS when diagnosing CKD
- Accelerated progression of CKD - >25% or > 15GFR dec in 1 year
- Visible or persistent invisible hematuria
- Symptoms of urinary tract obstruction
- Fhx of PCKD & are over 20 yrs old
- GFR < 30
- Who would need a renal biopsy
who would you refer to renal specialist for further care when diagnosing CKD
- eGFR <30 or a dec of >25%/15ml/min in the last 12 months
- ACR of >70mg/mmol
- ACR of >30mg/mmol + persistent haematuria + ruled out UTI
- Poorly controlled hypertension
- Rare/genetic cause of kidney disease
- Suspected renal artery stenosis
- Renal anaemia
what is the pharmacological treatment of CKD
HTN control
- • Off a renin-angiotensin system antagonist to people with CKD and
o DM and ACR >3
o HTN and ACR > 30
o ACR > 70
o Renin-angiotension sytem antagonist ACEi, ARB, renin blocker (Aliskiren), alderstone antagonist (spironolactone)
• Follow normal HTN guideline for CKD + HTN + ACR < 30
atorvastatin 20mg
aspirin or clopidergrea for secondary preventionm of CKD
apixaban if eGFR 30-50 + non-valvular AF + prior stroke/>75/HTN/DM/symptomatic heart failure
what are the causes of secondary HTN
Conn’s adenoma
renovascular disease
phaeochromocytoma
definition of white coat HTN?
blood pressure that is unusually raised when measured during consultations with clinicians but return to normal when measured in ‘non-threatening’ suitations
- difference in measurement by 20/10 mmHG
what BP measure is stage 1 HTN
clinic BP - > 140/90
ABPM/HBPM - 135/85 average
what BP measure is stage 2 HTN
clinic - 160/100
ABPM/HBPM - 150/95
what BP measure is severe HTN
clinic - > systolic 180 or diastolic > 110
definition of accelerated HTN
clinic BP - > 180 + signs of papilloedema +/- retinohaemorrhage
Pathophysiology of HTN
- Blood pressure is dependent on cardiac output and peripheral resistance
- Cardiac output is determined by stroke volume and heart rate
- Stroke volume is related to myocardial contractility and size of the vascular compartment
- Cardiac output is ↑ early in the disease course
- Then cardiac output ↓ but total peripheral resistance ↑
- Why this happens is not well understood but there are 3 theories:
- 1) over-reactive renin-angiotensin system = vasoconstriction and retention of Na and H20
- 2) Overactive sympathetic nervous system = ↑ stress response
Aetiology/RF of HTN?
- Age — blood pressure tends to rise with advancing age.
- Sex — Up to about 65 years, women tend to have a lower blood pressure than men. Between 65 to 74 years of age, women tend to have a higher blood pressure.
- Ethnicity — people of Black African and Black Caribbean origin are more likely to be diagnosed with hypertension.
- Genetic factors — research on twins suggest that up to 40% of variability in blood pressure may be explained by genetic factors.
- Social deprivation — people from the most deprived areas in England are 30% more likely to have hypertension than those from the least deprived.
- Lifestyle — smoking, excessive alcohol consumption (recently shown that this has a large influence on BP), excess dietary salt, obesity, and lack of physical activity are associated with hypertension.
- Anxiety and emotional stress — can raise blood pressure due to increased adrenaline and cortisol levels.
how you would you measure BP in clinic
1) measure BP in both arms
- if > 15 difference, measure a 2nd time
- if still different, take the higher reading
2) if BP reading > 140/90 during clinic, take a 2nd reading
- if still significantly different, take a 3rd reading and record the lowest 2 reading
how you confirm a diagnosis of HTN
if clinic reading between 140/90 and 160/110, the offer ABPM or HBPM for confirmation
if clinic reading > 180/120 but no signs of papilloedema and retinal haemorrhage –> repeat BP reading in clinic in 7 days but investigates for end-organ damages
if clinic reading > 180/120 + signs of papilloedema and retinal haemorrhage –> refer to specialist same day