C-Reactive Protein (CRP) in Neonates: Comparing VITROS Slide and High-Sensitivity CRP Methods

Abstract

C-reactive protein (CRP) is measured on VITROS® Chemistry Systems (Ortho-Clinical Diagnostics) using a “MicroSlide” method. At our hospitals plasma CRP concentrations <10 mg/L are used as an indicator that it is safe to discontinue antibiotic therapy in neonates with known or suspected sepsis (1). After implementing the neonatal sepsis protocol, we found that the VITROS CRP slide gave results up to 33 mg/L higher in neonatal specimens (Fig. 1⇓ , open triangles) than the Behring Nephelometer II (BNII, Dade Behring) high-sensitivity CRP (hsCRP) assay, a well-characterized method for CRP measurements(2). Figure 1. Bland-Altman plot showing the difference between CRP by VITROS and comparative methods. Δ, VITROS CRP Slide vs Behring Nephelometer II. ▪, VITROS hsCRP MicroTip method vs Behring Nephelometer II, DPC IMMULITE, or Roche Integra. Dotted vertical line is the sepsis protocol decision …