{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,5]],"date-time":"2026-08-05T01:47:03Z","timestamp":1785894423931,"version":"3.56.0"},"reference-count":22,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T00:00:00Z","timestamp":1780272000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,8,5]],"date-time":"2026-08-05T00:00:00Z","timestamp":1785888000000},"content-version":"vor","delay-in-days":65,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["BMC Pediatr"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>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.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>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)\u2009&gt;\u20091.0\u00a0mg\/dL were excluded. ID was defined as age-specific low serum ferritin and\/or transferrin saturation (TSAT)\u2009&lt;\u200916%. 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.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>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.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>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.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1186\/s12887-026-07080-2","type":"journal-article","created":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T04:35:42Z","timestamp":1780288542000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Relatively high prevalence of subclinical iron deficiency in Japanese children: evidence from a preoperative screening cohort"],"prefix":"10.1186","volume":"26","author":[{"given":"Yamato","family":"Hanawa","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuji","family":"Baba","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wataru","family":"Murasaki","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hiroyuki","family":"Namba","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kimihiko","family":"Oishi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,6,1]]},"reference":[{"issue":"4","key":"7080_CR1","doi-asserted-by":"publisher","first-page":"527","DOI":"10.1007\/s00431-020-03597-5","volume":"179","author":"V Mattiello","year":"2020","unstructured":"Mattiello V, Schmugge M, Hengartner H, von der Weid N, Renella R, SPOG Pediatric Hematology Working Group. Diagnosis and management of iron deficiency in children with or without anemia: consensus recommendations of the SPOG Pediatric Hematology Working Group. Eur J Pediatr. 2020;179(4):527\u201345.","journal-title":"Eur J Pediatr"},{"issue":"5 Suppl 1","key":"7080_CR2","doi-asserted-by":"publisher","first-page":"S1468","DOI":"10.1093\/jn\/133.5.1468S","volume":"133","author":"J Beard","year":"2003","unstructured":"Beard J. Iron deficiency alters brain development and functioning. J Nutr. 2003;133(5 Suppl 1):S1468\u201372.","journal-title":"J Nutr"},{"issue":"2","key":"7080_CR3","doi-asserted-by":"publisher","first-page":"54","DOI":"10.1179\/147683010X12611460763689","volume":"13","author":"AF Lukowski","year":"2010","unstructured":"Lukowski AF, Koss M, Burden MJ, Jonides J, Nelson CA, Kaciroti N, Jimenez E, Lozoff B. Iron deficiency in infancy and neurocognitive functioning at 19 years: evidence of long-term deficits in executive function and recognition memory. Nutr Neurosci. 2010;13(2):54\u201370.","journal-title":"Nutr Neurosci"},{"issue":"9","key":"7080_CR4","doi-asserted-by":"publisher","first-page":"e0273819","DOI":"10.1371\/journal.pone.0273819","volume":"17","author":"S McWilliams","year":"2022","unstructured":"McWilliams S, Singh I, Leung W, Stockler S, Ipsiroglu OS. Iron deficiency and common neurodevelopmental disorders-A scoping review. PLoS ONE. 2022;17(9):e0273819.","journal-title":"PLoS ONE"},{"issue":"6","key":"7080_CR5","doi-asserted-by":"publisher","first-page":"e2021055926","DOI":"10.1542\/peds.2021-055926","volume":"150","author":"A Gingoyon","year":"2022","unstructured":"Gingoyon A, Borkhoff CM, Koroshegyi C, Mamak E, Birken CS, Maguire JL, Fehlings D, Macarthur C, Parkin PC. Chronic Iron Deficiency and Cognitive Function in Early Childhood. Pediatrics. 2022;150(6):e2021055926.","journal-title":"Pediatrics"},{"key":"7080_CR6","doi-asserted-by":"publisher","unstructured":"Duran BC, Ay Y, Imancli H, Akcay G. The Effect of Iron Deficiency Anemia and Serum Ferritin Deficiency on Cognitive Functions in Children 1 to 5 Years Old. J Pediatr Hematol Oncol. 2025. https:\/\/doi.org\/10.1097\/MPH.0000000000003090.","DOI":"10.1097\/MPH.0000000000003090"},{"issue":"5","key":"7080_CR7","doi-asserted-by":"publisher","first-page":"1040","DOI":"10.1542\/peds.2010-2576","volume":"126","author":"RD Baker","year":"2010","unstructured":"Baker RD, Greer FR, Committee on Nutrition American Academy of Pediatrics. Diagnosis and prevention of iron deficiency and iron-deficiency anemia in infants and young children (0\u20133 years of age). Pediatrics. 2010;126(5):1040\u201350.","journal-title":"Pediatrics"},{"issue":"6","key":"7080_CR8","doi-asserted-by":"publisher","first-page":"283","DOI":"10.3345\/cep.2023.00521","volume":"67","author":"NH Lee","year":"2024","unstructured":"Lee NH. Iron deficiency in children with a focus on inflammatory conditions. Clin Exp Pediatr. 2024;67(6):283\u201393.","journal-title":"Clin Exp Pediatr"},{"key":"7080_CR9","volume-title":"Guideline on haemoglobin cutoffs to define anaemia in individuals and populations","author":"World Health Organization","year":"2024","unstructured":"World Health Organization. Guideline on haemoglobin cutoffs to define anaemia in individuals and populations. Geneva: WHO; 2024."},{"issue":"1","key":"7080_CR10","doi-asserted-by":"publisher","first-page":"31","DOI":"10.1002\/ajh.24201","volume":"91","author":"M Auerbach","year":"2016","unstructured":"Auerbach M, Adamson JW. How we diagnose and treat iron deficiency anemia. Am J Hematol. 2016;91(1):31\u20138.","journal-title":"Am J Hematol"},{"issue":"3","key":"7080_CR11","doi-asserted-by":"publisher","first-page":"452","DOI":"10.1038\/bmt.2012.244","volume":"48","author":"Y Kanda","year":"2013","unstructured":"Kanda Y. Investigation of the freely available easy-to-use software \u2018EZR\u2019 for medical statistics. 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BMC Pediatr. 2021;21(Suppl 1):337.","journal-title":"BMC Pediatr"}],"container-title":["BMC Pediatrics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/article\/10.1186\/s12887-026-07080-2","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1186\/s12887-026-07080-2.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1186\/s12887-026-07080-2.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,5]],"date-time":"2026-08-05T00:55:44Z","timestamp":1785891344000},"score":1,"resource":{"primary":{"URL":"https:\/\/link.springer.com\/10.1186\/s12887-026-07080-2"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,1]]},"references-count":22,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2026,12]]}},"alternative-id":["7080"],"URL":"https:\/\/doi.org\/10.1186\/s12887-026-07080-2","relation":{},"ISSN":["1471-2431"],"issn-type":[{"value":"1471-2431","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,6,1]]},"assertion":[{"value":"21 December 2025","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"27 May 2026","order":2,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"1 June 2026","order":3,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"This retrospective study was approved by the Ethics Committee of Jikei University (#36\u2013344). All participants were minors. In accordance with national regulations and institutional policy for retrospective studies using routinely collected clinical data, the Ethics Committee waived the requirement for informed consent from parents or legal guardians. The study was conducted using de-identified data. An opt-out consent procedure was implemented by public notice (institutional website and hospital posting), allowing parents or legal guardians to refuse participation.","order":1,"name":"Ethics","label":"Ethics approval and consent to participate","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"Not applicable.","order":2,"name":"Ethics","label":"Consent for publication","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"The authors declare no competing interests.","order":3,"name":"Ethics","label":"Competing interests","group":{"name":"EthicsHeading","label":"Declarations"}}],"article-number":"707"}}