Pediatric reference ranges for creatine kinase, CKMB, troponin I, iron, and cortisol

Boyajian

et al. 2006

Clinica Chimica Acta

Background-Brain natriuretic peptide (BNP) and N-terminal pro-brain natriuretic peptide (NTproBNP) have been shown to be useful biomarkers for the diagnosis of heart failure. Pediatric reference intervals for these analytes have been reported in part. Previous studies lack large numbers in each group, have not covered all age ranges and have not compared results for BNP with NT-proBNP in simultaneously drawn samples.Methods-We measured BNP in whole blood using the Biosite Triage point-of-care method and plasma NT-proBNP using the Dade RxL Dimension. We assessed between and within-day precision of both methods and after removing outliers employed the Hoffmann approach to calculate pediatric reference intervals over the age range of 0-21 y. We also compared the 2 methods on simultaneously drawn samples.Results-Reference intervals revealed approximately 20-fold higher 97.5th percentiles for neonates than for children >3 y of age. 97.5th percentiles decreased significantly over the first 3 years of life. As shown by others, the CVs for the automated Dade RxL platform were somewhat lower than those for the POCT method. BNP and NT-proBNP correlated well in simultaneously drawn samples (r =0.947).Discussion-Reference intervals for BNP and NT-proBNP are far higher in neonates and infants than in children older than three years of age. The reasons for this are unknown but resemble the elevated CK-MBs and troponins also found in neonates, although the 97.5th percentiles for these latter 2 cardiac markers decrease more rapidly to values found in older children by 6 months of age.

Section: Discussionsupporting

confidence: 57%

Pediatric brain natriuretic peptide and N-terminal pro-brain natriuretic peptide reference intervals

Boyajian

et al. 2006

Clinica Chimica Acta

“…Notice that the upper cortisol ranges are higher for sick patients than for healthy individuals, no doubt due to the stress of illness. We have reported this observation before using other immunoassay methods (Table 6) [10].…”

Section: Resultsmentioning

confidence: 57%

Pediatric reference intervals for FSH, LH, estradiol, T3, free T3, cortisol, and growth hormone on the DPC IMMULITE 1000

Hoffman

Waring

et al. 2005

Clinica Chimica Acta

Background-We studied serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), triiodothyronine (T3), free T3 (FT3), cortisol and growth hormone (GH) concentrations in a population of pediatric patients. The reference intervals were determined separately for females and males stratified by age groups to assess age-and sex-related differences. Our objective was to obtain reference intervals for the 7 serum analytes for our pediatric population using the IMMULITE 1000 system. Methods-Serum samples of 800 in-and out-patients, newborn to 19 years old were analyzed using the DPC IMMULITE 1000 chemiluminescent immunoassay system.Results and conclusions-We report pediatric reference intervals for FSH, LH, E2, T3, FT3, cortisol, and GH. These reference intervals provide the basis for clinical interpretation of laboratory results using the IMMULITE 1000 system and the assessment of child development.

“…An abnormal result obtained for any of the analytes studied would lead to physician concern and intervention. As with other reference intervals published previously by our group [1,4,6,7,[22][23][24] these new ranges have been implemented at Children's National Medical Center since August 07 and have been well accepted by the medical staff. They are applied to results obtained for both in-and outpatients.…”

Section: Resultsmentioning

confidence: 58%

IMMULITE® 2000 age and sex-specific reference intervals for alpha fetoprotein, homocysteine, insulin, insulin-like growth factor-1, insulin-like growth factor binding protein-3, C-peptide, immunoglobulin E and intact parathyroid hormone

Dahlin

Gresham

et al. 2008

Clinical Biochemistry

Objectives-To determine age and sex-specific pediatric reference intervals for serum alpha fetoprotein, homocysteine, insulin, insulin-like growth factor-I, insulin-like growth factor binding protein-3, C-peptide, immunoglobulin E and parathyroid hormone.Design and methods-The study was conducted at both Children's National Medical Center and Georgetown University, Washington D.C. Results for the above analytes were obtained from the Children's National Medical Center laboratory information system over the period of 1/5/2001-3/8/2007.Patient results using the IMMULITE 2000® were accessed and used to establish reference intervals for the analytes studied. All patient identifiers were removed except age and sex. Analysis of the data was performed at Georgetown University in the Bioanalytical Core Laboratory. The data was analyzed using the Hoffmann approach, and was computer adapted. The number of patient samples studied varied with each analyte and were: Alpha fetoprotein (557), homocysteine (924), insulin-like growth factor-1 (1352), insulin-like growth factor binding protein-3 (711), insulin (3239), C-peptide (267), immunoglobulin E (2691) and parathyroid hormone (513).Results and conclusions-This study provides pediatric reference intervals for the eight analytes for children from birth to 18 years of age. All the analytes exhibited at least some age dependence. Sex differences between early and late childhood and adolescence were also frequently found.