Endocrine Abstracts

Introduction: Obesity as a pro-inflammatory state is associated to increased levels of C-reactive protein (CRP). CPR is considered as a cardiovascular (CV) risk independent marker and is being researched as a predictive atherosclerosis biomarker in obese children. The American Heart Association (AHA) recommends a three classes approach when aiming at CV risk stratification (low <1.0 mg/l; moderate 1.0–3.0 mg/l; and high >3.0 mg/l). These classes were extrapolated to the paediatric aged patients.

Objective: Compare the performance of two different CPR assays, using blood samples from an obese paediatric population.

Methods: 79 patients were enrolled (convenience sample) (ages 12–17). Serum CPR levels were simultaneously assayed using two distinct analytical methods: Classic wide rage CPR assay (wrCPR Siemens Latex enhanced immunoturbidimetry; ADVIA 2400; CMD=0.03 mg/l normalization: CRM 470 IFCC), and high sensitivity PCR (CardioPhase hsCRP Siemens BNproSpec Siemens CMD=0.175 mg/l). SPSS 20V Software was used for statistical analysis.

Results: The correlation coefficient (R=0.9971) (P<0.001) (Pearson’s test) showed a very strong positive correlation between the two assays (y=1.26x−0.34). The Bland–Altman dispersion plot, pointed that the inter assay (absolute (AD) and percentual (PD)) differences were in 95% CI (except one outlier (>10 mg/l) (AD) and the six lowest pairs (PD)). PCR values of both assays were stratified according to AHA CV risk classes (72 pairs (91.14%) were grouped in the same class, including the aforementioned six lowest pairs). The Fleiss’ test (κ=0.858) (P<0.001) showed a very strong AHA class agreement of both assays.

Conclusion: A strong correlation and agreement has been shown between the two assays.