Predictive Role of Reticulocyte Fluorescence for Late Red Blood Cell Transfusion in Very Low Birth Weight Infants

Background. Nearly 58% of very low birth weight (VLBW) infants receive at least one red blood cell transfusion, which is not without risk. Reticulocyte fluorescence (RF) indicates the degree of cell maturation. The greater the fluorescence, the greater the immaturity of the reticulocytes. Aim. To evaluate RF as a marker of reticulocyte maturity and to investigate its predictive value for transfusion requirement in VLBW infants. Methods. Complete blood count was performed at 1, 7, 14, 21, and 28 d of age in 104 VLBW infants at the University Hospital of Parma. Iron supplementation was started at 15 d of life. The infants were divided into two groups: those who required transfusion after 28 d of life. (Tr) and those who did not (NTr). Results. Twenty-seven of 104 newborns required a red blood cell transfusion after 28 d of life (Tr group). At 14 d of life, the percentage of high fluorescence reticulocyte (HFR) was significantly higher in the r group than in infants who did not receive any transfusion (NTr groups): 18.5 vs. 5%, p = 0.002. The ROC curve (AUC 74%) revealed an HFR cut-off value of 16.5% as a predictor of the need for red blood cell (RBC) transfusion. Conclusions. Reticulocyte maturation at 14 d of life is clinically useful for estimating the qualitative impairment of erythropoiesis and predicts the risk of RBC transfusion in VLBW infants. The data suggest the need for tailored iron integration in VLBW infants to improve the quality of hematopoiesis and reduce the risk of blood transfusion. (c) 2024 Published by Elsevier Inc. on behalf of Instituto Mexicano del Seguro Social (IMSS).