Early-Life Clinical and Hematological Profiles: Distinguishing Infants and Toddlers with Sickle Cell Disease

Recent research shows a substantially higher early hospital admission burden among children with sickle cell disease, driven largely by severe anemia and divergent hematologic trajectories from birth through age three.

Neonatal HbF is strikingly high (≈72–73%) and its rate of decline correlates with event frequency. Mechanistically, HbF blunts polymerization of HbS and reduces early sickling, so a faster fall in HbF plausibly unmasks hemolysis and vaso‑occlusive risk. Clinically, this study supports serial hemoglobin‑fraction checks to track risk, and monitoring HbF trends helps surface the hemolysis signal for early intervention.

SCD infants have lower hemoglobin and red‑cell indices, persistent reticulocytosis, and higher white‑cell counts compared with controls. Early morbidity is concentrated: admissions were 19.6% in children with SCD versus 1.7% in controls, with severe anemia accounting for the majority of SCD hospitalizations. These hematologic patterns are actionable—they identify infants who need expedited hematology follow‑up after newborn screening.

The cohort suggests that hematologic markers could enable risk stratification but does not yet define validated operational thresholds or multivariable prediction tools. The findings also support consideration of earlier hydroxyurea in selected high‑risk infants on biological grounds, while stopping short of a policy change without randomized or trial evidence. As a result, it's important to integrate routine HbF and CBC monitoring into newborn‑screening pathways and prioritize prospective predictive‑model work and pragmatic trials to establish thresholds for intensified follow‑up and earlier initiation of disease‑modifying therapy.