{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,13]],"date-time":"2026-06-13T04:56:21Z","timestamp":1781326581307,"version":"3.54.1"},"reference-count":17,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,6,8]],"date-time":"2026-06-08T00:00:00Z","timestamp":1780876800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Hematology Reports"],"abstract":"<jats:p>Background\/Objectives: The Duffy (Fy) blood group system, encoded by the ACKR1 gene, plays a key role in transfusion medicine and host susceptibility to malarial infections such as Plasmodium vivax. The Duffy-null phenotype [Fy(a\u2212b\u2212)] is associated with lower baseline white blood cell (WBC) and absolute neutrophil count (ANC) values despite a benign clinical course. This study aimed to establish specific reference intervals for WBC and ANC in Duffy-null individuals to improve diagnostic accuracy and reduce unnecessary clinical interventions. Methods: We conducted a retrospective analysis of 1695 adult patients who underwent complete blood count testing and red blood cell phenotyping between 1 January 2020 and 1 January 2026. Among these, 122 healthy individuals with confirmed Fy(a\u2212b\u2212) phenotype met inclusion criteria. Reference intervals were established using 95% reference interval nonparametric methods in accordance with Clinical Laboratory Standards Institute (CLSI) guidelines. Results: The median WBC and ANC values in the Duffy-null cohort were significantly lower than institutional reference medians (3.24 vs. 6.65 \u00d7 103\/\u00b5L and 1.45 vs. 4.45 \u00d7 103\/\u00b5L, respectively; p &lt; 0.01). The derived 95% reference intervals (WBC: 2.43\u20137.05 \u00d7 103\/\u00b5L; ANC: 1.01\u20134.34 \u00d7 103\/\u00b5L) fell below conventional thresholds, with the lower ANC bound below the standard neutropenia cutoff. Conclusions: These findings support the need for Duffy-null-specific hematologic reference ranges. Adoption of such intervals may reduce misclassification, avoid unnecessary diagnostic procedures, and promote personalized clinical care.<\/jats:p>","DOI":"10.3390\/hematolrep18030038","type":"journal-article","created":{"date-parts":[[2026,6,8]],"date-time":"2026-06-08T16:25:16Z","timestamp":1780935916000},"page":"38","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Establishing Reference Intervals for White Blood Cell and Absolute Neutrophil Counts in Duffy Null Individuals"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2761-4320","authenticated-orcid":false,"given":"Mohammad","family":"Barouqa","sequence":"first","affiliation":[{"name":"Department of Pathology, University of South Alabama, 2451 University Hospital Dr, Mobile, AL 36617, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Muhammad Areeb","family":"Ashfaq","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Hematology and Medical Oncology Division, University of South Alabama, 2451 University Hospital Dr, Mobile, AL 36617, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-7935-2452","authenticated-orcid":false,"given":"Katrina J.","family":"Jiang","sequence":"additional","affiliation":[{"name":"Department of Pathology, University of South Alabama, 2451 University Hospital Dr, Mobile, AL 36617, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-4689-1343","authenticated-orcid":false,"given":"Huseyin","family":"Kilic","sequence":"additional","affiliation":[{"name":"Department of Pathology, University of South Alabama, 2451 University Hospital Dr, Mobile, AL 36617, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nestor","family":"Dela Cruz","sequence":"additional","affiliation":[{"name":"Department of Pathology, University of South Alabama, 2451 University Hospital Dr, Mobile, AL 36617, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aariez","family":"Khalid","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, University of South Alabama, 2451 University Hospital Dr, Mobile, AL 36617, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2032-7356","authenticated-orcid":false,"given":"Marianne E.","family":"Yassa","sequence":"additional","affiliation":[{"name":"Department of Pathology, University of South Alabama, 2451 University Hospital Dr, Mobile, AL 36617, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,8]]},"reference":[{"key":"ref_1","first-page":"93","article-title":"Molecular basis of the Duffy blood group system","volume":"16","author":"Fiegenbaum","year":"2018","journal-title":"Blood Transfus."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"202","DOI":"10.1111\/vox.70148","article-title":"International Society of Blood Transfusion Working Party on Red Cell Immunogenetics and Blood Group Terminology Report of Gothenburg, Barcelona and four virtual business meetings: Update on blood group systems","volume":"121","author":"Hyland","year":"2026","journal-title":"Vox Sang."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"4751","DOI":"10.1016\/j.cell.2024.07.005","article-title":"Molecular mechanism of distinct chemokine engagement and functional divergence of the human Duffy antigen receptor","volume":"187","author":"Saha","year":"2024","journal-title":"Cell"},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Kranjc, A., Narwani, T.J., Abby, S.S., and De Brevern, A.G. 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Med."}],"container-title":["Hematology Reports"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2038-8330\/18\/3\/38\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,13]],"date-time":"2026-06-13T04:11:29Z","timestamp":1781323889000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2038-8330\/18\/3\/38"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,8]]},"references-count":17,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2026,6]]}},"alternative-id":["hematolrep18030038"],"URL":"https:\/\/doi.org\/10.3390\/hematolrep18030038","relation":{},"ISSN":["2038-8330"],"issn-type":[{"value":"2038-8330","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,6,8]]}}}