Reference intervals of automated reticulocyte count and immature reticulocyte fraction in a pediatric population.

Introduction: Reticulocytes are erythroid precursors that develop into mature erythrocytes, and they are an important tool to assess erythropoietic activity, as their count indicates the balance between the cells released from the bone marrow, their stage of maturity, and their rate of development into mature erythrocytes. Considering the described biological variability of the absolute reticulocyte count (ARC) and the immature reticulocyte fraction (IRF) and the limited information available on these hematological parameters in children, this study determined the reference intervals (RIs) of these parameters in a healthy pediatric population.

Methods: A retrospective, observational, and analytical study was designed to establish RIs for the ARC and the IRF according to age and sex.