C-reactive protein (CRP) in cord blood: Is "negative" CRP negative?

Serum concentration of C-reactive protein (CRP) has a high specificity, but low sensitivity in the early diagnosis of neonatal bacterial infection. Its sensitivity may be increased by determination of CRP - concentrations below 0,5 mg/dl, the lowest detection limit of conventional tests. Information on CRP-concentrations below 0.5 mg/dl in healthy newborns is limited. We measured CRP in cord blood sera of 60 consecutive healthy term infants using a high sensitive Latex-nephelometry with a lower detection limit of 0,02 mg/dl. 98% of the 60 eligible infants had cord blood CRP - concentrations I 0,02 mg/dl. Our results are useful for the interpretation of CRP-levels between 0,02 mg/dl - 0,5 mg/dl in infants suspicious of neonatal infection.