Accuracy of Reticulocyte Hemoglobin for Diagnosing Iron Deficiency in Very Preterm Infants: A Population-Based Cohort Study

• Published in: Blood 2023-11, Vol.142 (Supplement 1), p.5229-5229
• Main Authors: Barr, Hudson, Kulkarni, Ketan, Singh, Balpreet, Sandila, Navjot, Morrison, Lisa, Beach, Lori, Ghotra, Satvinder
• Format: Article
• Language: English
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood-2023-179515

Background: Preterm born infants are at an increased risk of developing iron deficiency (ID) despite preventative iron supplementation, which can lead to long-term negative neurodevelopmental and behavioral outcomes. Serum ferritin (SF) is the commonly used test for diagnosing ID. However, SF is influenced by infection and inflammation, making it an unreliable marker in such situations. An alternative, reticulocyte hemoglobin equivalent (Ret-He), measures the iron content in newly produced red blood cells, providing an immediate assessment of iron availability. Unlike SF, Ret-He tests are automated, can be performed on the same blood sample as a complete blood count, and is not influenced by infection or inflammation like SF. However, there is limited literature on the reliability of Ret-He as an ID marker in very preterm infants (VPI) during their first year of life. This study aims to evaluate the diagnostic accuracy of Ret-He as an ID indicator in VPI at 4-6 months of corrected age (CA) compared to SF levels. Objective: To investigate the accuracy of Ret-He in detecting ID in VPI at 4-6 months CA Methods: A retrospective population-based cohort study was conducted using a population-based Provincial Perinatal Follow-Up (PFUP) database on all live VPIs born in Nova Scotia between 2012 and 2018. Infants with hematological disorders, chromosomal abnormalities, or major congenital anomalies were excluded. Prophylactic iron supplementation (2-3 mg/kg/day) starting at 2-4 weeks of chronological age was a standard of care for all included infants. Iron supplementation was recommended until 9-12 months CA. All infants underwent SF and CBC testing at either 4- or 6-months CA to assess iron stores and guide supplementation. In 2012, Ret-He was added as an additional marker of ID for clinical decision-making. Two definitions of ID were used. Definition one defined ID as SF level