Red Cell Distribution Width to Platelet Count Ratio Reference Intervals in Premature Infants Beyond the First Week of Life.

Objective: Red cell distribution width (RDW) is a parameter of complete blood count (CBC). The RDW to platelet count ratio (RPR) is a new index that has been shown to reflect the severity of inflammation. We aim to determine the reference interval (RI) of RPR for premature newborns. Study design: The medical records of preterm infants who were followed up between January 2016 and December 2018 were reviewed. CBC levels were measured in 144 infants at <72 hours of age. Results: CBCs of infants (gestational age from 28 to 35weeks) had a RI of 0.038-0.126 for the RPR. The RI for RPR in infants with a gestational age of 32-35weeks was 0.042-0.129; and the RI for infants at 28-31weeks was 0.022-0.121. Conclusion: Establishment of RI for RPR in premature infants will allow clinical correlation of RPR alterations in this population.