Sepsis is a leading cause of morbidity and mortality among newborns. C-reactive protein (CRP) and procalcitonin (PCT) have some limitations in the diagnosis of preterm neonatal sepsis. In this study, the cut-offs of PCT and CRP, and the efficacy of mean platelet volume (MPV) were investigated. | The cut-off levels of procalcitonin and Creactive protein and the kinetics of mean platelet volume in preterm neonates with sepsis