Serum C-Reactive Protein in the Early Diagnosis of Neonatal Septicemia and Bacterial Meningitis

The usefulness of serum C-reactive protein (CRP) in the early detection of neonatal infection was studied using a special laser nephelometric apparatus (CRP-1), by which CRP concentrations could be quickly determined in the nursery, with only a small amount of serum (20 μL). Initial serum CRP concentrations of samples obtained from 90 infants suspected to have sepsis and/or meningitis were evaluated. Of the 90 infants, 25 showed culture-proven septicemia and/or bacterial miningitis, while 18 were considered to be infectious based on clinical signs and positive sepsis work-up even though cultures were negative. 47 infants had negative cultures and sepsis work-up and showed a favorable clinical courses. Statistical analysis for the evaluation of serum CRP at the level of one mg/dL was performed. False negative CRP was demonstrated in seven of 25 infants with culture-proven sepsis and/or meningitis (28%) and in 4 of 18 infants with other infections (22%). On the other hand, seven of 47 (15%) non-infected infants showed false positive results. The specificity and sensitivity of serum CRP determination were 85% and 74%, respectively, for all patients, and 85% and 72%, respectively, for patients with sepsis and/or meningitis. The sensitivity varied with the pathogens. We conclude that, while the initial CRP values alone are unsatisfactory for deciding the need for antibiotic therapy, CRP is useful in the early detection of neonatal infections, and its measurement by this new equipment should available in the nursery.