Plasma lactoferrin levels in newborn preterm infants with sepsis.

Introduction: Lactoferrin (Lf) is one of the major proteins of all exocrine secretions with a role in the antinfective process. Our aim was to evaluate how plasma Fl levels may change in response to infection in newborn preterm infants.

Methods: A total of 15 (8 females, 7 males) newborn preterm infants with a postnatal age >72 h of life, underwent to blood culture and others markers of infection, for suspected sepsis, were enrolled in the study.

Results: We found that Lf serum concentration was significantly lowest in four neonates (26.7%) with confirmed sepsis than in 11 (73.3%) with clinical sepsis. The AUC was 0.90 (95%CI: 0.63-0.99). The optimal cutoff for Lf was <1.2 μg/ml with a sensibility of 100% and a specificity of 81.8%. Lf serum concentration was positively correlated with WBC or neutrophil (Spearman rho = 0.69 and 0.49, respectively).

Conclusions: Serum Lf could prove a promising, sensitive and specific marker in the diagnostic approach to infants with suspected sepsis, thanks to its role in defense mechanisms and physiological functions of the immune system. Low levels of Lf in sepsis may suggest an immature response due to suboptimal leukocites activity in newborn preterm infants.