{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,30]],"date-time":"2026-08-30T11:33:50Z","timestamp":1788089630457,"version":"build-2803163510"},"reference-count":13,"publisher":"BMJ","issue":"1","content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Case Rep"],"accepted":{"date-parts":[[2026,1,7]]},"published-print":{"date-parts":[[2026,1]]},"abstract":"<jats:p>Leukemoid reaction, a non-malignant leucocytosis (total leucocyte count\u226530\u2009000\u201350\u2009000\u2009\/mm\u00b3) is typically triggered by infection, malignancy or drug exposure. Its occurrence after intravenous iron infusion is rare. An elderly man in his mid-70s with a history of prostate cancer (in remission), hypertension and osteoarthritis developed acute onset leucocytosis (&gt;30\u2009000\/mm\u00b3) with systemic inflammatory signs (myalgia, malaise, elevated C reactive protein), transaminitis and acute kidney injury following his second ferric carboxymaltose infusion for iron deficiency anaemia. Extensive investigation ruled out infection and malignancy. His condition improved with supportive care and returned to baseline, aided by preserved physiological reserve. Though uncommon, leukemoid reaction should be considered as a potential adverse event of ferric carboxymaltose infusion in older adults even when prior doses were tolerated. Incorporating geriatric assessment may help predict resilience and guide management.<\/jats:p>","DOI":"10.1136\/bcr-2025-268222","type":"journal-article","created":{"date-parts":[[2026,1,22]],"date-time":"2026-01-22T14:05:16Z","timestamp":1769090716000},"page":"e268222","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":1,"title":["Leukemoid reaction following ferric carboxymaltose infusion in an elderly patient"],"prefix":"10.1136","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-6540-6100","authenticated-orcid":false,"given":"Venugopal","family":"Mantry","sequence":"first","affiliation":[{"name":"Department of Geriatric Medicine, All India Institute Of Medical Sciences New Delhi, New Delhi, Delhi, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Akshata","family":"Rao","sequence":"additional","affiliation":[{"name":"Department of Geriatric Medicine, All India Institute Of Medical Sciences New Delhi, New Delhi, Delhi, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-6115-7962","authenticated-orcid":false,"given":"Swarup","family":"Das","sequence":"additional","affiliation":[{"name":"Department of Geriatric Medicine, All India Institute Of Medical Sciences New Delhi, New Delhi, Delhi, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Avinash","family":"Chakrawarty","sequence":"additional","affiliation":[{"name":"Department of Geriatric Medicine, All India Institute Of Medical Sciences New Delhi, New Delhi, Delhi, India"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2026,1,22]]},"reference":[{"key":"2026062608101442000_19.1.e268222.1","unstructured":"Holland SM , Gallin JI . Disorders of granulocytes and monocytes. In: Jameson JL , Fauci AS , Kasper DL , et al ., eds. Harrison\u2019s principles of internal medicine. 21st ed. 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J Hematol Oncol Pharm 2023;13."},{"key":"2026062608101442000_19.1.e268222.6","doi-asserted-by":"crossref","first-page":"1660","DOI":"10.1016\/j.jaip.2020.11.028","article-title":"Safety of Intravenous Iron Following Infusion Reactions","volume":"9","author":"Stojanovic","year":"2021","journal-title":"J Allergy Clin Immunol Pract"},{"key":"2026062608101442000_19.1.e268222.7","doi-asserted-by":"publisher","DOI":"10.3324\/haematol.2014.111492"},{"key":"2026062608101442000_19.1.e268222.8","doi-asserted-by":"publisher","DOI":"10.1001\/jama.1962.03050520030012a"},{"key":"2026062608101442000_19.1.e268222.9","doi-asserted-by":"crossref","first-page":"589","DOI":"10.1080\/08998280.2019.1641045","article-title":"Vitamin B12 deficiency mimicking acute leukemia","volume":"32","author":"Konda","year":"2019","journal-title":"Baylor Univ Med Center Proc"},{"key":"2026062608101442000_19.1.e268222.10","doi-asserted-by":"publisher","DOI":"10.1378\/chest.07-2114"},{"key":"2026062608101442000_19.1.e268222.11","doi-asserted-by":"publisher","DOI":"10.1093\/cid\/cit562"},{"key":"2026062608101442000_19.1.e268222.12","first-page":"223","article-title":"Iron-induced endothelial cell damage: mechanisms and implications","volume":"33","author":"van Rensburg","year":"2020","journal-title":"Biometals"},{"key":"2026062608101442000_19.1.e268222.13","doi-asserted-by":"publisher","DOI":"10.1016\/j.exger.2005.06.009"}],"container-title":["BMJ Case Reports"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1136\/bcr-2025-268222","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,26]],"date-time":"2026-06-26T15:21:08Z","timestamp":1782487268000},"score":1,"resource":{"primary":{"URL":"https:\/\/casereports.bmj.com\/lookup\/doi\/10.1136\/bcr-2025-268222"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,1]]},"references-count":13,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2026,1,22]]},"published-print":{"date-parts":[[2026,1]]}},"alternative-id":["10.1136\/bcr-2025-268222"],"URL":"https:\/\/doi.org\/10.1136\/bcr-2025-268222","relation":{},"ISSN":["1757-790X"],"issn-type":[{"value":"1757-790X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,1]]}}}