Abstract Background Iron deficiency (ID), even in the absence of anemia, is one of the most common micronutrient deficiencies in childhood and remains particularly relevant during infancy and early childhood, when brain development is rapid. Iron plays an essential role in myelination, neurotransmitter synthesis, mitochondrial function, and neuronal energy metabolism. Contemporary longitudinal and mechanistic studies suggest that early-life iron deficiency may be associated with later deficits in attention, executive function, and educational performance, although the magnitude and reversibility of these effects remain incompletely defined. Methods We retrospectively reviewed pediatric patients who underwent elective surgery between January 2021 and June 2024. Patients with hematologic disorders, severe chronic disease, ongoing iron therapy, clinically active inflammatory conditions, or preoperative C-reactive protein (CRP) > 1.0 mg/dL were excluded. ID was defined as age-specific low serum ferritin and/or transferrin saturation (TSAT) < 16%. Anemia was defined using the 2024 World Health Organization hemoglobin cutoffs. Cases with discordant ferritin and TSAT results were classified as ID if either criterion was abnormal. Results Of 199 eligible patients, 129 were included (76 males, 53 females). The majority were aged 6 months to 4 years. ID was identified in 26 children (20.2%), including 23 with ID without anemia and 3 with IDA (2.3%); all were asymptomatic. The ID group showed lower hemoglobin, MCV, MCH, serum iron, and ferritin, and higher RDW-CV, platelet count, and UIBC than the non-ID group. Conclusions Subclinical ID was common among asymptomatic Japanese children undergoing elective surgery, indicating that clinically silent iron deficiency may be present even in children who appear otherwise well. Rather than supporting surgery-based screening as a stand-alone strategy, these findings underscore the importance of careful dietary and clinical risk assessment during routine pediatric care and the need for context-sensitive approaches to early identification of children at risk for iron deficiency.
Hanawa et al. (Mon,) studied this question.