A detailed analysis of changes in serum C-reactive protein levels in neonates treated for bacterial infection

A prospective study was undertaken to characterize the rate of increase. ti me of peak values and rates of decrease in serum concentrations of C-reacti ve protein (CRP) in a group of infants treated for neonatal bacterial infec tion. A total of 176 consecutively admitted neonates with birth weight > 15 00 g and without mechanical ventilation or central lines in situ, who recei ved antibiotic therapy for suspected bacterial infection, were enrolled. Th e changes in serum CRP concentration in 60 of 63 infants who had CRP values above 20 mg/l 24-48 h after the beginning of treatment were analysed in de tail. Initial increase rates in serum CRP levels of up to 4.5 mg/l per h we re documented peak were reached at a mean of 19.5 h after antibiotic therap y had been initiated, but in some patients an increase in serum CRP levels occurred up to 40-48 h after the beginning of treatment. The mean serum hal f-life of CRP in infected neonates was 21 h (range 11.2-38 h). Conclusion In neonates with bacterial infection (defined by a combination o f clinical signs and increased C-reactive protein and immature-total quotie nt values) no differences in the overall pattern nor in any of the particul ar phases of the C-reactive protein response curves could be observed betwe en neonates with positive (n = 13) or negative blood cultures (n = 47).