Serum C‐reactive protein is a useful marker for congenital infection

Serial quantitative measurements of C-reactive protein (CRP) were performed by reaction rate nephelometry on cord blood and scrum of 70 babies (60 preterm and 10 full term). There were 41 babies born to mothers with no risk factors for bacterial infection (Group 1) and 29 babies born to mothers with risk factors (Group 2), Maternal risk factors for congenital infection were: a history of prolonged rupture of membranes, maternal treatment with antibiotics, chorioamnionitis or positive cultures from high vaginal swabs. Twelve babies had raised CRP levels (>10 mg/1), 2 from Group 1 and 10 from Group 2, 9 of whom were subsequently found to have bacterial infections. One of the 2 babies without suspected infection had severe birth asphyxia. Specificity, sensitivity, positive and negative predictive values were calculated for CRP levels and total white cell counts (TWCC). Within Group 2, the specificity of raised CRP for diagnosis of congenital bacterial infection was 95% and the sensitivity was 100%, compared to the specificity of TWCC 95% and sensitivity 55%. CRP can be used as a marker for congenital bacterial infection and appears to be more sensitive than TWCC.