Infection in late preterm infants

Abstract

Background: Late preterm (LP) are at higher risk than term infants to develop infections due to their more immature immune system. Little data about the risks and incidence of infection and sepsis in LP are present in literature.

Aims: To evaluate treated infection rates and risk factors for infection in moderate and late preterm infants (gestational age = 32-36 weeks).

Study design: We retrospectively studied a population of 771 moderate and late preterm infants consecutively admitted to our unit from June 2008 to November 2013.

Results: Treated infections were 128, with an incidence of 16.6%; the 90% (n = 115) occurred during the first 72 hours of life. Blood cultures were positive in 22% of cases, umbilical venous catheter cultures were positive in 26% of cases; Coagulase-negative staphylococci were the most frequently isolated pathogens. Patients of the sepsis group had a C-reactive protein (CRP) mean value of 28.27 mg/L and a procalcitonin mean value of 25.3 μg/L. Risk factors for infections were umbilical venous catheter (UVC) insertion (χ(2) = 15.9; p ≤ 0.05), prophylaxis with antenatal corticosteroids (χ(2) = 16.7; p ≤ 0.05) and birth by cesarean section, with observed values very similar to the expected values (χ(2) = 15.9; p = 0.1). Respiratory symptoms were found in 47 of the 60 patients in the sepsis group (78.3%).

Conclusions: Late and moderate preterm infants have an increased significant risk of infection compared to term infants. Infections, given the high frequency of negative cultures in neonates, should be often suspected and treated on the basis of clinical features and inflammatory markers, trying always to avoid a possible overtreatment.

Keywords: Biomarkers; Cultures; Infection; Late preterm; Neonatal sepsis.