321 - Bacterial attributes in chorioamnionitis affects blood inflammatory indices in very preterm infants

Poster Number: 321
Publication Number: 321.439

Taketoshi Yoshida, Toyama university hospital, toyama, Toyama, Japan; Takashi Okuno, Department of Pediatrics, Faculty of Medical Sciences, University of, eiheiji-cho, Yoshida-gun, Fukui, Japan; Kentaro Tamura, University of Toyama, Toyama, Toyama, Japan; Kenta Matsumura, University of Toyama, Toyama, Toyama, Japan; Hideki Niimi, Toyama University Hospital, Toyama, Toyama, Japan

Background: Although chorioamnionitis (CAM) is associated with preterm delivery, there is no consensus on whether CAM increases the risk of neonatal complications such as bronchopulmonary dysplasia (BPD), intraventricular hemorrhage, and cerebral palsy. Accurate assessment of the severity of CAM may help clarify the inflammatory effects of CAM on fetus.

Objective: This study aimed to investigate the relationship between bacterial properties in CAM and blood inflammatory indices at birth in very preterm infants.

Design/Methods: Very preterm infants (gestational age ≤30 weeks) were included. Bacterial isolates from neonatal gastric fluid at birth were identified and the number of bacteria was measured by quantitative-PCR. Interleukin-6 (IL-6) level in cord blood and white blood cell (WBC), leukocyte fraction, C-reactive protein, and IgM levels in neonatal blood were measured. We divided the infants into 3 groups according to the kind of bacteria: (1) no bacteria (under the limit of detection); (2) Ureaplasma and/or Mycoplasma; (3) bacteria other than Ureaplasma and Mycoplasma. The species and number of bacteria in neonatal gastric fluid and blood inflammatory indices were compared.

Results: The study included 42 preterm infants (mean gestational age: 27.0 weeks; mean birth weight: 966 g). Histological CAM was found in 30 mothers (71%) and stage 3 was most common. The median cord blood IL-6 level was 4.321 pg/mL and fetal inflammatory response syndrome was found in 24 newborns (57.1%). Twenty-six newborns (62%) had at least one type of bacteria in their gastric fluid. The number of bacteria showed significant correlation with cord blood IL-6, neonatal WBC, neutrophils, and IgM levels. WBCs and neutrophils were significantly increased in Ureaplasma and/or Mycoplasma infection.Conclusion(s): Bacterial load in gastric fluid is associated with blood inflammatory markers at birth in very preterm infants. Leukocytosis and neutrophilia in Ureaplasma and/or Mycoplasma infection with CAM may be involved in the pathogenesis of neonatal complications such as BPD.