Are Complete Blood Cell Counts Useful in the Evaluation of Asymptomatic Neonates Exposed to Suspected Chorioamnionitis?
* Department of Pediatrics, Division of Neonatal-Perinatal Medicine, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas
Parkland Health and Hospital System, Dallas, Texas
Objective. Chorioamnionitis complicates 1% to 10% of pregnancies and increases the risk of neonatal infection. Women with chorioamnionitis receive intrapartum antibiotics, often resulting in inconclusive neonatal blood cultures. Peripheral neutrophil values are used frequently to assist in the diagnosis of neonatal infection and to determine duration of antibiotics; we sought to determine the utility of this approach.
Methods. A prospective observational study was performed in 856 near-term/term neonates who were exposed to suspected chorioamnionitis. Each received antibiotics for 48 hours unless clinical infection or positive blood cultures occurred. Peripheral neutrophils were measured serially and analyzed using the reference ranges of Manroe et al; an additional analysis of only the initial neutrophil values used the normal ranges of Schelonka et al. Results of neutrophil analyses were not used to determine duration of therapy. Fifty percent of asymptomatic neonates were seen postdischarge to ascertain recurrent infection. Local patient charges were examined.
Results. Ninety-six percent of neonates were asymptomatic and had negative cultures, and antibiotics were discontinued at 48 hours. A total of 2427 neutrophil counts were analyzed. Although abnormal neutrophil values were more frequent in infected or symptomatic neonates, 99% of asymptomatic neonates had 
1 abnormal value. The specificity and negative predictive values for abnormal neutrophil values ranged between 0.12 and 0.95 and 0.91 and 0.97, respectively; sensitivity was 0.27 to 0.76. Significant differences in interpretation of the initial neutrophil values were noted, depending on the normal values used. Follow-up was performed for 373 asymptomatic neonates until 3 weeks’ postnatal age. Eight required rehospitalization; none had evidence of bacterial infection. If neutrophil values had been used to determine duration of antibiotics, then local costs would have increased by $76 000 to $425 000 per year.
Conclusions. Single or serial neutrophil values do not assist in the diagnosis of early-onset infection or determination of duration of antibiotic therapy in asymptomatic, culture-negative neonates who are 35 weeks’ gestation and are delivered of women with suspected chorioamnionitis.
Key Words: intraamniotic infection • neutrophil values • complete blood count • early-onset infection • antibiotic therapy • length of stay • resource utilization
Abbreviations: CDC, Centers for Disease Control and Prevention • CBC, complete blood cell count • ATN, absolute total neutrophil count • ATI, immature neutrophil count • I:T, immature neutrophil count:absolute total neutrophil count proportion • NBN, normal newborn nursery • GBS, group B streptococcus
Received for publication Jun 19, 2003; Accepted Jan 5, 2004.
CiteULike 
Connotea 
Del.icio.us 
Digg 
Facebook 
Reddit 
Technorati 
Twitter What's this?
This article has been cited by other articles:
|
|
 |
|
  P. F. Tumbaga and A. G.S. Philip Perinatal Group B Streptococcal Infections and the New Guidelines: An Update NeoReviews, October 1, 2006; 7(10): e524 - e530. [Full Text] [PDF]
|
|
|
|
 |
|
 CBCs, Neonates, and Chorioamnionitis Journal Watch (General), June 1, 2004; 2004(601): 4 - 4. [Full Text]
|
|
eLetters:
Read all eLetters
- Labor and stress at delivery are confounders in the evaluation of neonatal sepsis
- Eleanor J Molloy, et al.
- Pediatrics Online, 28 May 2004 [Full text]
