Increased inflammatory markers are associated with early periventricular leukomalacia

The aim of the study was to investigate whether inflammatory markers are associated with the occurrence of periventricular leukomalacia (PVL). Superoxide (O-2(-)) production of neutrophils and plasma antioxidative superoxide dismutase (SOD) activity in umbilical cord blood were studied. Participants were preterm infants with early PVL (n=6; three males, three females; mean birthweight 1458g [SD 517], range 620-2040g; mean gestational age 29.8wks [SD 2.9], range 27-34wks); and preterm control infants without PVL (n=10; five males, five females; mean birthweight 1838g [SD 664], range 925-2748g; mean gestational age 30.6wks [SD 3.1], range 26-34wks). In addition, pro-inflammatory cytokine levels were measured in the umbilical cord blood. N-formyl-methionyl-leucyl-phenylalanine-induced O-2(-) production by neutrophils in infants with early PVL was significantly higher than that in the control group. In contrast, there was no significant difference in concentrations of copper/zinc-SOD and SOD activity between groups. Concentrations of interleukin (IL)-1 beta and tumour necrosis factor-alpha (but not IL-6, IL-8, or granulocyte-colony stimulating factor) were significantly higher in infants with early PVL than in control infants. The excess O-2(-) produced by activated neutrophils with increased pro-inflammatory cytokine production could play a role in the molecular cascade leading to white matter damage in PVL.