Late-onset sepsis in very low birth weight (VLBW) infants is a diagnostic challenge. We aimed to evaluate the diagnostic utility of the C-Reactive protein (CRP) and the complete blood count (CBC) for late-onset sepsis in VLBW infants.
In a 5-year retrospective cohort of 416 VLBW infants born at less than 1500 g, there were 590 separate late-onset sepsis evaluations. CRP and CBC were drawn at time of initial blood culture (T0), at 16–24 h (T24) and 40–48 h (T48) after. The positive cut-off values for abnormal values were the following: CRP ≥10 mg/L and CBC with at least one anomaly, including white blood cell count < 5000/mm3, immature neutrophil/total neutrophil ratio > 0.10, or platelet count < 100,000/uL. Sensitivity and specificity for predicting late-onset sepsis were calculated for each laboratory test and their combinations. Receiver operating characteristics curves were obtained for each test and for the absolute change from T0 to T24 in the laboratory value of CRP, white blood cell count and immature neutrophil/total neutrophil.
At T0, combining the CBC and the CRP had the highest sensitivity of 66% (95% confidence interval [CI], 58–73) compared to both individual tests for predicting late onset sepsis. At T24, CRP’s sensitivity was 84% (95% CI, 78–89) and was statistically higher than the CBC’s 59% (95% CI, 51–67). The combination of CBC at T0 and CRP at T24 offered the greatest sensitivity of 88% (95% CI, 82–92) and negative predictive value 93% (95% CI, 89–96), with fewer samples, compared to any other combination of tests. The area under the curve for the change in the white blood cell count from T0 to T24 was 0.82.
At initial sepsis evaluation (T0), both CBC and CRP should be performed to increase sensitivity. A highly negative predictive value is reachable with only two tests: a CBC at T0 and a CRP a T24.
Fanaroff AA, Korones SB, Wright LL, Verter J, Poland RL, Bauer CR, et al. Incidence, presenting features, risk factors and significance of late onset septicemia in very low birth weight infants. The National Institute of Child Health and Human Development neonatal research network. Pediatr Infect Dis J. 1998;17(7):593–8. CrossRefPubMed
Arnon S, Litmanovitz I, Regev R, Lis M, Shainkin-Kestenbaum R, Dolfin T. The prognostic virtue of inflammatory markers during late-onset sepsis in preterm infants. J Perinat Med. 2004;32(2):176–80. PubMed
Marchant EA, Boyce GK, Sadarangani M, Lavoie PM. Neonatal sepsis due to coagulase-negative staphylococci. Clin Dev Immunol. 2013;5(8):60–76.
Hentges CR, Silveira RC, Procianoy RS, Carvalho CG, Filipouski GR, Fuentefria RN, et al. Association of late-onset neonatal sepsis with late neurodevelopment in the first two years of life of preterm infants with very low birth weight. J Pediatr. 2014;90(1):50–7. CrossRef
Pourcyrous M, Bada HS, Korones SB, Baselski V, Wong SP. Significance of serial C-reactive protein responses in neonatal infection and other disorders. Pediatrics. 1993;92(3):431–5. PubMed
Shah J, Jefferies AL, Yoon EW, Lee SK, Shah PS, Network CN. Risk factors and outcomes of late-onset bacterial sepsis in preterm neonates born at < 32 Weeks’ gestation. Am J Perinatol. 2015;32(7):675–82. PubMed
Rewa O, Muscedere J, Reynolds S, Jiang X, Heyland DK. Coagulase-negative staphylococcus, catheter-related, bloodstream infections and their association with acute phase markers of inflammation in the intensive care unit: an observational study. Can J Infect Dis. 2012;23(4):204–8.
- C-reactive protein for late-onset sepsis diagnosis in very low birth weight infants
- BioMed Central