Embed Size (px)
Citation preview
CKD.
• CKD is defined as abnormalities of kidney
structure or function, present for > 3 months,
with implications for health.
• CKD is classified based on cause, GFR
category, and albuminuria category (CGA).
Inulin clearance.
• Inulin is a sugar which is filtered by the glomerulus and neither reabsorbed nor secreted into the tubule.
• The gold standard is to inject inulin into the blood and measure the clearance of inulin in the urine.
GFR = Vol of urine per time X Conc of inulin in urine
Conc of inulin in blood
1
3
2
4
5
6
7
8
9
10
55 65 75 85 95 105 115 125 135
.
Patient
Cr (mmol/L)
Population ref. range
Problems with S Cr: Variability
• Up to 50% loss of GFR
can occur with serum creatinine
remaining within population
reference range
C inulin (ml/min/1.73m2)
Seru
m c
reatin
ine (m
mol/L
)
Creatinine-’blind’
region
0 20 40 60 80 100 120 140 160 180
100
200
300
400
500
600
700
900
1000
Problems with Serum Creatinine: Insensitive
0 55 125
Population ref. range
Estimated GFR.
• More typically derived formula, using a single
blood test of the serum creatinine, which is used
to calculate the estimated glomerular filtration
rate (eGFR).
• Cockcroft and Gault, MDRD, CKD-EPI.
• GFR=141 × min(Scr/κ, 1)α × max(Scr/κ, 1)−1.210 ×
0.993Age × 0.993 [if female] × 1.16 [if Black] ×
1.05 [if Asian] × 1.01 [if Hispanic and Native
American]
CKD - Staging
• Divided into 5 stages:
CKD 1 GFR > 90 ml/min
CKD 2 GFR 60- 90 ml/min
CKD 3a GFR 45 - 60 ml/min
CKD 3b GFR 30 – 45 ml/min
CKD 4 GFR 15- 30 ml/min
CKD 5 GFR < 15 ml/min
Albuminuria
• Is a marker of renal disease and
prognosis.
• Addition of albuminuria to staging:
A1 < 30 mg/mmol
A2 30-300 mg/mmol
A3 >300mg/mmol
Renal prognosis.
Other implications.
RRT in NZ.
Over 4000 people on RRT in NZ.
CKD in NZ is unknown but estimated as:
CKD 5 = 3000
CKD 4 = 8000
CKD 3 = 70,000
CKD 2 = 170,000
CKD 1 = >250,000
Sociodemographic risk factors.
• Age – more common in the elderly
• Sex – more common in men
• Ethnicity – more common in Asians, Pacific
Island peoples and Māori.
Cases.
• What is the classification for the renal disease?
• What else would you like to know?
• What other investigations are needed?
• What are the key management points?
Case 1.
• 54 year old Samaon lady
DM for 12 years, HT, Dyslipidaemia
Aspirin 100mg, Metformin 500mg tds,
Cilazapril 5mg, Simvastatin 20mg
Wt 100kg, BMI 37, BP 150/90mmHg
Cr 140umol/L, Urine ACR 70, HbA1c 60
Discussion
• Diabetic nephropathy
• Major cause of CKD (>40%)
• Serial Cr and urinalysis
• Optimise HbA1c
• Lower BP 130/80mmHg (diuretic/CCB)
• No absolute need for imaging
Case 2.
• 43 year old Chinese man
Usually well.
Sore throat and macroscopic haematuria
No medications
Wt 67kg, BP 150/90mmHg, BMI 24
Cr 140umol/L, MSU RCC >1000, Urine ACR 40
Renal Biopsy – Histology.
Renal Biopsy – Immuno (IgA)
Discussion.
• Probably glomerulonephritis (30%-35% of
ESKD).
• ANA, ANCA, dsDNA, C3, C4,
streptococcal serology, hepatitis serology.
• US and renal biopsy (confirms IgA)
• Treat BP 140/90mmHg or lower
(ACEI/ARB)
Case 3.
• A 39 year old lady presents for routine
renewal of the OCP. She has a family
history of polycystic kidney disease.
She is on no other regular medications.
Wt 67kg, BP 150/90mmHg, BMI 24
Cr 80umol/L, MSU RCC 10, Urine ACR 20
Imaging.
Discussion.
• PCKD (10% ESKD).
• U/S renal tract
• Treat BP 140/90mmHg or lower
• New agents coming (Sirolimus Tolvaptan)
• Advice about family hx and screening
• Advice about stones, infections and
aneurysms.
Case 4.
• 68 year old man with hypertension, Type 2 DM.
On Aspirin 100mg, Metoprolol 47.5mg daily,
Pravastatin 10mg daily, Metformon 850mg tds
• Examination:
HR 72/min, BP 160/90mmHg, JVP 2cm, Wt 98kg
• Investigations:
Na 140, K 5.0, Cr 150µmol/L, urine ACR 10, HbA1c 49
Discussion.
• Probably HT nephrosclerosis
• Do bloods and US renal tract
• Try to optimise BP 140/80mmHg or lower
Case 5.
• 82 year old man with hypertension, osteoarthritis,
GOR, gout and COAD. Has recently completed
antibiotics (Augmentin). On Cilazapril 5mg,
Bendrofluazide 5mg, omeprazole 20mg daily,
allopurinol 100mg, serevent and flixotide. Takes
diclofenac SR 75g mgs 1-2/week.
• Examination:
HR 72/min, BP 150/90mmHg, JVP 1cm, No oedema
RR 18/min, wheeze, PEFR 300l/min
• Investigations:
Na 140, K 5.0, Urea 10, Cr 140µmol/L, urine ACR 10
Discussion.
• Multiple potential causes for renal
impairments HT, drugs.
• Probably not significantly abnormal for his
age.
• Try stopping diuretic and starting CCB
• Consider stopping PPI and NSAID
Case 6.
• 35 year old Samoan man. Usually fit and well.
Presents for a well man check.
• Examination:
Wt 100kg, HR = 70/min, BP 112/60mmHg, no oedema
• Investigations:
Na 140mmol/L, K 4.5mmol/L, urea 6.0mmol/L, Cr
125µmol/L, urine ACR 3
Discussion.
• Probably not abnormal for his age.
• Could do a urinalysis and 24 hour
creatinine clearance to check.
Creatinine and eGFR.
Serum Cr 140 mmol/L
GFR = 120 ml/min GFR = 20 ml/min
Renal Function changes with age.
0
20
40
60
80
100
120
140
160
1801
6-2
9
30
-39
40
-49
50
-59
60
-69
70
-79
80
-89
90
-99
Age (years)
eG
FR
(m
L/m
in/1
.73
m2
)
0
10
20
30
40
50
60
Low Limit
Median
High Limit
60 mL/min
%<60 mL/min
Based on 200,000 routine pathology results, courtesy Dr Ken Sikaris
Causes of CKD.
• The most common causes of CKD are:
Diabetic nephropathy 40%
Glomerulonephritis 30%
Hypertensive nephrosclerosis 10%
Polycystic kidney disease 10%
Slowing progression.
• Intervention into the primary renal disease
• Intervention into secondary factors
Diabetes
Hypertension.
• Progression of CRF has been linked to HT.
• Lowering BP alters speed of progression.
Renal survival and hypertension.
50
70
90
0 6 12 18 24 30
Months
Ren
al s
urvi
val (
%)
< 107mmHg
> 107mmhg
Locatelli et al. NDT 1996
Hypertension.
• Target 140/80 mmHg or better
• Weight loss
• Salt restriction
• Exercise
• Moderation of alcohol
• Stop smoking
Drugs and hypertension.
MDRD ABCD HOT UKPDS
Goal BP MAP < 92
mmHg DBP < 75
mmHg DBP < 80
mmHg DBP < 85
mmHg
Achieved BP 93 mmHg 75 mmHg 81 mmHg 82 mmHg
Average number
of drugs 3.6 2.7 3.3 2.8
HT drugs
• Naturesis (diuretics)
• Renin : angiotensin system
• Sympathetic nervous system
Complementary Drugs.
(RAAS +/- SNS blockade) (Natriuretic +/-vasodilator)
Beta blockers Diuretics
ACE inhibitors CCB
ARB’s Alpha-blocker
Clonidine Minoxidil
Methyldopa
Good and bad combinations
• Good
Thiazide and ACEI
ACE and CCB
B-blocker and α-blocker
Thiazide and CCB
• Bad
ACEI and B-blocker
ARB and B-blocker
ACEI and ARB
Screening – as part of CV risk.
• Hypertension
• Diabetes
• BMI > 35
• Cardiovascular disease
• Family history of kidney disease
• Prostatic syndrome/urologic disease
• Nephrotoxic drugs
• Māori, Pacific Island People or Indo- Asians
• Age over 60 years.
Who to refer.
• Intrinsic kidney disease
• Drug-resistant hypertension
• Progressive Stage 3B and 4 CKD
• CKD 5
• Where uncertainty about management or
referral exists, use of telephone consultations
and/or ‘virtual’ referrals is highly recommended
Interesting Links.
• http://www.rnzcgp.org.nz/assets/documents/Sta
ndards--Policy/Consultations/CKD-consensus-
statement-25-Sept-2013.pdf
• http://www.kdigo.org/clinical_practice_guidelines
/pdf/CKD/KDIGO_2012_CKD_GL.pdf
• http://jama.jamanetwork.com/article.aspx?articlei
d=1791497
