Relationship between Histologic Chorioamnionitis and Early Inflammatory Variables in Blood, Tracheal Aspirates, and Endotracheal Colonization in Preterm Infants

Abstract

Histologic results of the placenta are usually not available within the first days of life. We identified inflammatory variables in tracheal aspirates and blood that were associated with histologic chorioamnionitis (HC). A derivation cohort consisted of 62 neonates and a validation cohort of 57 neonates with a gestational age Ͻ 31 wk and ventilated on d 1. Tracheal aspirates were taken on d 1 and on d 3, if the patient was still ventilated. HC was diagnosed by light microscopy. Logistic regression was used to identify independent factors in the derivation cohort associated with HC at d 1, 2, and 3. Model performance was studied using receiver operating characteristic curve analysis. Independent factors associated with HC were, at d 1, tracheal aspirate IL-8 Ն 917 pg/mL (odds ratio, 60.7; 95% confidence interval, 11-328); at d 2, blood C-reactive protein Ն 14 mg/L (odds ratio, 9.2; 95% confidence interval, 2-38), blood white blood cell count Ն 10,400/mm 3 (odds ratio, 7.4; 95% confidence interval, 2-28); and at d 3, blood neutrophil count Ն 4968/mm Chorioamnionitis is considered to be one of the main causes of preterm labor and has been associated with an adverse perinatal outcome (e.g. cerebral palsy and chronic lung disease) in preterm infants (1, 2). Histologic results of the examination of the placenta are usually not available within the first days of life, and prenatal diagnosis of chorioamnionitis remains difficult. An early diagnosis is difficult and can only be made in 6% to 24% of these patients by amniotic fluid culture (3). As a result of the "chronic inflammation" of fetal or maternal membranes, elevated proinflammatory cytokine levels are found in the amniotic fluid and ultimately in the fetus. These cytokines are associated with preterm labor and delivery, a fetal inflammatory response, and the associated negative outcomes (4, 5).The objective of the present study was to identify variables in the TA and blood of preterm infants, measured within the first 3 d of life, that are associated with HC in the placenta. These factors would allow us to identify infants with the highest risk of suffering from the adverse consequences of chorioamnionitis. METHODS Study population.

Nuclear Factor κB Activation in Pulmonary Leukocytes from Infants with Hyaline Membrane Disease: Associations with Chorioamnionitis and Ureaplasma urealyticum Colonization

“…Significantly higher levels of TNF-␣ and IL-8 were found in the tracheal aspirates of this group, suggesting increased severity of inflammation in this group. This extends the work of Watterberg et al (21), who showed elevation of IL-1␤ in first-day aspirates from infants who were exposed to intrauterine inflammation, and is also consistent with recently published evidence for IL-8 being an accurate indicator of histologic chorioamnionitis (54). A notable finding in our study is that significantly more infants with chorioamnionitis had lung neutrophils and macrophages expressing NF-B activation in the first week of life.…”

Association of BPD and IVH with early neutrophil and white counts in VLBW neonates with gestational age <32 weeks

“…Infections and inflammatory processes in both the mother and infant are involved. 20,21 High white counts in our population appear partly explained by maternal infections, as exposure to PROM and chorioamnionitis were common at high total WBC. Low neutrophil counts were very rare in these groups, however.…”

Endotracheal Colonization at Birth Is Associated with a Pathogen-Dependent Pro- and Antiinflammatory Cytokine Response in Ventilated Preterm Infants: A Prospective Cohort Study

“…Recently, we demonstrated that TA pro-inflammatory cytokines (e.g. IL-8) measured immediately after birth are significantly increased in infants born from mothers with histologic chorioamnionitis (8).…”