Abstract
INTRODUCTION: Infection is a risk factor for adverse neurodevelopmental outcome in preterm newborns. Our objective was to characterize the association of postnatal infection with adverse microstructural and metabolic brain development in premature newborns. RESULTS: In 34/117 newborns studied, clinical signs were accompanied by positive cultures whereas 17 had clinical signs of sepsis alone. White matter injury (WMI) was identified in 34 newborns. In multivariate regression models, infected newborns had brain imaging measures indicative of delayed brain development: lower N-acetylaspartate/choline, elevated average diffusivity (D(AV)), and decreased white matter fractional anisotropy. These widespread brain abnormalities were found in both newborns with positive-culture infection and in those with clinical infection. DISCUSSION: These findings suggest that postnatal infection, even without a positive culture, is an important risk factor for widespread abnormalities in brain development. These abnormalities extend beyond brain injuries apparent with conventional magnetic resonance injury (MRI). METHODS: 117 preterm newborns (24-32 wk gestation) were studied prospectively at a median of 32.0 and 40.3 wk ostmenstrual age with MRI (WMI, hemorrhage), magnetic resonance (MR) spectroscopy (metabolism), and diffusion tensor imaging (microstructure). Newborns were categorized as having "no infection," "clinical infection," or "positive-culture infection." We compared brain injuries as well as metabolic and microstructural development across these infection groups.