reference values for serum creatinine concentrations in...
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Reference values for serum creatinineReference values for serum creatinineconcentrations with Jaffe-compensated
assay in Iranian adult subjectsassay in Iranian adult subjects
Asghar Ghasemi Iraj Azimzadeh Saleh Zahediasl Fereidoun AziziAsghar Ghasemi, Iraj Azimzadeh, Saleh Zahediasl, Fereidoun Azizi
Endocrine Physiology Research Center, Research Institute forEndocrine Sciences, Shahid Beheshti University of MedicalSciences,Tehran, Iran
IntroductionChronic kidney disease is a worldwide public health problem with
increasing prevalence and incidenceg p
Glomerular filtration rate (GFR), the best overall index of renal
function, is mostly estimated from serum creatinine concentration
Any equation using serum creatinine level for estimating GFR is
dependent on the serum creatinine assayp yLevey AS: Ann Intern Med 139:137-147, 2003------------- Hosseinpanah F: BMC Public Health 9:44, 2009Levey AS: Ann Intern Med 130:461-470, 1999--------------- Selvin E: Am J Kidney Dis 50:918-926, 2007
Coresh J: Am J Kidney Dis 39:920-929, 2002--------------- Hetu PO: Clin Biochem 43:1158-1162, 2010yKuster N: Clin Biochem 45:320-325, 2012--------
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IntroductionSerum creatinine concentration is affected by factors other than creatinine filtration
including:including:
Sex
Age
Race
Diet
Muscle mass
Analytical methodLevey AS: Ann Intern Med 130:461-470, 1999 Ceriotti F: Clin Chem 54:559-566 2008Ceriotti F: Clin Chem 54:559-566, 2008Myers GL: Clin Chem 52:5-18, 2006
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IntroductionJaffe method, used in most routine laboratories, has a low specificity and
overestimates serum creatinine by approximately 20-30% at physiological
values, because of noncreatinine chromogens (mainly proteins)g ( y p )
Enzymatic creatinine methods are more specific and have been widely
adopted for routine clinical laboratory as alternatives to the alkaline picrate
h dmethods
Coresh J: Am J Kidney Dis 39:920-929, 2002ChromyV: Clin Chem Lab Med 46:1127-1133 2008ChromyV: Clin Chem Lab Med 46:1127-1133, 2008JungeW: Clin Chim Acta 344:137-148, 2004
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IntroductionFor serum creatinine, like other naturally occurring biochemical compounds, a
reference interval needs to be provided
Reports of reference intervals for serum creatinine levels in Asian populations,
considering IFCC (International Federation of Clinical Chemistry) criteria with
accurate description of the measurement method, are scant
To our knowledge, there is no documented report on reference values of serum
creatinine in Irancreatinine in Iran
Ceriotti F: Clin Chem 54:559-566, 2008--------- Jorgensen LG: Clin Chem Lab Med 42:817-823, 2004
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AimAimTo determine age and sex specific reference intervalsTo determine age- and sex-specific reference intervals
for serum creatinine concentration using data from a g
population-based study from Iran
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Subjects and Methods
Subjects
Participants of Tehran Lipid and Glucose Study (TLGS) from June Participants of Tehran Lipid and Glucose Study (TLGS) from June
2008 to September 2011
Number of subjects
5247 apparently healthy participants (2792 men and 2455 women), 5247 apparently healthy participants (2792 men and 2455 women),
aged 20 to 88 years
Separate analysis was done for healthy menopausal women (n= 452;
age range 51-84 years). g g y
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Subjects and MethodsExclusion criteria
Pregnancy
Hypertension
Diabetes
History of cardiovascular disease, cancer, and diarrhea
History of hospitalization during the past 3 months
History of significant weight loss during past 6 months
Using medications including steroids, diuretics, betablockers, digitals, calcium channelg g , , , g ,
blockers, angiotensin converting enzyme inhibitors, aspirin and other anticoagulants,
lipid lowering drugs, male or female hormones, contraceptives (oral or injection), or
drugs for thyroid disordersDr. Ghasemi9
Subjects and MethodsCreatinine measurement
Serum creatinine was measured using the photometric Jaffe methodSerum creatinine was measured using the photometric Jaffe method
(Pars Azmoon Kit,Tehran, Iran)
In 382 samples, creatinine measurement was done with both Jaffe
and enzymatic p-aminophenazone (PAP) methodsy p p ( )
Method for determining reference values:
IFCC criteria (non-parametric method)( p )
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R lResults
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Regression line between Cr measurement with Jaffe and PAP (enzymatic) methods
2 5
Jaffe Cr = 0.863 × PAP Cr + 0.44 mg/dL
r = 0 973 n= 383 p < 0 001)
2.0
2.5 r 0.973, n 383, p < 0.001)dL
)
1.0
1.5
e cr
eatin
ine
(mg/
d
0.5
Jaff
0.0 0.5 1.0 1.5 2.0 2.50.0
PAP creatinine (mg/dL)
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Bland-Altman method comparison for comparingcreatinine measurements by Jaffe and PAP methods
0.5
creatinine measurements by Jaffe and PAP methods
0.4
Mean =0.32 ± 0.05
+2SD=0.42
0 2
0.3
ea 0 3 0 05
-2SD =0.22
P (m
g/dL
)
0.1
0.2
Jaffe
- PA
P
0.5 1.0 1.5 2.0 2.50.0
Mean of Jaffe and PAP creatinine (mg/dL)
-0.1Dr. Ghasemi13
Comparison of serum creatinine concentration according to sex and age*: significant difference with other groups
1.0 WomenMen
: significant difference with other groups†: significant difference compared to men
0.7
0.8
0.9*
* †
0.80
ol/L
)
0 4
0.5
0.6 *†
crea
tinin
e ( μ
m
0.2
0.3
0.4
Seru
m
20-2
9
30-3
9
40-5
0
> 50
20-2
9
30-3
9
40-5
0
> 50
en-to
tal
en-to
tal0.0
0.1
0.57
A ( ) Me
Wom
eAge groups (years)
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Reference intervals for serum creatinine concentration (mg/dL) in healthy d l bj di d i h d J ff h dadult subjects according to age and sex using the compensated Jaffe method
Age (years) n 95% Reference intervals Men 20-29 856 0.53-1.00 30-39 633 0.53-1.00 40-50 701 0 53-1 110.53 1.11 >50 602 0.53-1.11 All 2792 0.53-1.11WomenWomen 20-29 972 0.31.77 30-39 818 0.42-0.77
40 50 665 40-50 665 0.42-0.77 >50 452 0.42-0.88 All 2455 0.42-0.77
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Di i Discussion
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Serum creatinine reference values (mg/dL) in selected countries
Age Creatinine reference values MethodCountry year
Age
(years)
Creatinine reference values
(μmol/L)
Method
Males Females
S th A t li (Ad l id ) 2000 18 70 0 70 1 20 0 50 0 91 C t d J ffSouth Australia (Adelaide) 2000 18-70 0.70-1.20 0.50-0.91 Compensated Jaffe
Germany 2004 18-74 0.71-1.17 0.54-0.96 Compensated Jaffe
Nordic countries 2004 ≥18 0 70 1 20 0 63 1 00
Compensated Jaffe
(Denmark, Finland, Iceland,
Norway, and Sweden) 2004 ≥18 0.70-1.20 0.63-1.00
India 2006 20-60 0.80-1.30 0.60-1.00 Enzymatic
S i 2007 19 65 0 72 1 20 0 59 0 96 C t d J ffSpain 2007 19-65 0.72-1.20 0.59-0.96 Compensated Jaffe
Belgium 2008 20-70 0.63-1.17 0.48-0.93 Enzymatic
Italy 2010 18-79 0.65-1.17 0.45-1.00 Compensated Jaffe
China 2011 20-91 0.66-1.11 0.49-0.79 Enzymatic
Kenya 2012 18-50 0.63-1.12 0.54-0.96 ND
Iran Present 20-88 0.53-1.11 0.42-0.77 Compensated
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Conclusion1. Reference intervals for serum creatinine concentration
according to compensated Jaffe method derived from aaccording to compensated Jaffe method, derived from a
population-based study in Iran, are 0.53-1.11 and 0.42-0.77
mg/dL in men and women respectively
2. Upper limits of serum creatinine reference values are lowerpp
than European countries and are close to the China and Kenya
3 h l ld b d f h di i d3. These values could be used for research, diagnostic and
therapeutic purposes
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Thanks
Intra-assay CVs were 2.2% and 3.1% for Jaffe and PAP methody J
respectively (n=72).
Inter-assay CVs for normal creatinine concentration were 4.1%
and 6.1% for Jaffe and PAP method respectively and for high
creatinine concentration were 1.3% and 1.7% for Jaffe and
PAP method respectively (n=17)PAP method respectively (n=17).
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