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A Murine Model of Fetal Exposure to Maternal Inflammation to Study the Effects of Acute Chorioamnionitis on Newborn Intestinal Development
Published on: June 24, 2020
Chorioamnionitis and Culture-Confirmed, Early-Onset Neonatal Infections
Jonathan M Wortham1, Nellie I Hansen2, Stephanie J Schrag3
1Epidemic Intelligence Service, Centers for Disease Control and Prevention, Atlanta, Georgia vij5@cdc.gov.
Insights
Some newborns exposed to chorioamnionitis may have early-onset group B streptococcal infections but show no symptoms. Current guidelines may lead to unnecessary antibiotic treatment for many uninfected infants.
Area of Science:
- Neonatal Medicine
- Infectious Diseases
- Public Health
Background:
- Current guidelines recommend evaluation and antibiotics for newborns exposed to chorioamnionitis.
- Concerns exist regarding these recommendations due to declining early-onset group B streptococcal disease rates and antibiotic risks.
Purpose of the Study:
- To determine if newborns with culture-confirmed early-onset infections and chorioamnionitis exposure can be asymptomatic at birth.
Main Methods:
- Prospective surveillance of early-onset neonatal infections (2006-2009).
- Maternal chorioamnionitis defined by clinical or histologic diagnosis.
- Retrospective review of hospital records to determine symptom onset in infected newborns.
Main Results:
- 232 of 389 early-onset infections occurred in newborns exposed to chorioamnionitis.
- 13% of these infants had no symptoms within 6 hours of birth; 9% remained asymptomatic at 72 hours.
- Intrapartum antibiotic prophylaxis exposure did not differ significantly between asymptomatic and symptomatic infants.
Conclusions:
- Some infants with culture-confirmed infections following chorioamnionitis may not exhibit sepsis signs at birth.
- Current guidelines may lead to early diagnosis but also overtreatment of uninfected infants.
Background:
Current guidelines for prevention of neonatal group B streptococcal disease recommend diagnostic evaluations and empirical antibiotic therapy for well-appearing, chorioamnionitis-exposed newborns. Some clinicians question these recommendations, citing the decline in early-onset group B streptococcal disease rates since widespread intrapartum antibiotic prophylaxis implementation and potential antibiotic risks. We aimed to determine whether chorioamnionitis-exposed newborns with culture-confirmed, early-onset infections can be asymptomatic at birth.
Methods:
Multicenter, prospective surveillance for early-onset neonatal infections was conducted during 2006-2009. Early-onset infection was defined as isolation of a pathogen from blood or cerebrospinal fluid collected ≤ 72 hours after birth. Maternal chorioamnionitis was defined by clinical diagnosis in the medical record or by histologic diagnosis by placental pathology. Hospital records of newborns with early-onset infections born to mothers with chorioamnionitis were reviewed retrospectively to determine symptom onset.
Results:
Early-onset infections were diagnosed in 389 of 396,586 live births, including 232 (60%) chorioamnionitis-exposed newborns. Records for 229 were reviewed; 29 (13%) had no documented symptoms within 6 hours of birth, including 21 (9%) who remained asymptomatic at 72 hours. Intrapartum antibiotic prophylaxis exposure did not differ significantly between asymptomatic and symptomatic infants (76% vs 69%; P = .52). Assuming complete guideline implementation, we estimated that 60 to 1400 newborns would receive diagnostic evaluations and antibiotics for each infected asymptomatic newborn, depending on chorioamnionitis prevalence.
Conclusions:
Some infants born to mothers with chorioamnionitis may have no signs of sepsis at birth despite having culture-confirmed infections. Implementation of current clinical guidelines may result in early diagnosis, but large numbers of uninfected asymptomatic infants would be treated.
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