{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,18]],"date-time":"2026-06-18T04:51:39Z","timestamp":1781758299240,"version":"3.54.5"},"reference-count":25,"publisher":"Oxford University Press (OUP)","issue":"6","license":[{"start":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T00:00:00Z","timestamp":1780272000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,6,4]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>In healthy individuals, CD34+\u2009stem cells are detectable in peripheral blood in relatively low and stable numbers. The clinical utility of peripheral blood CD34+\u2009stem cell quantitation in the evaluation of pancytopenia has not been systematically studied.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We used a large archival clinical cohort (n\u2009=\u2009154) of pediatric patients from our pediatric-only institution without a history of hematologic disorder or circulating blasts on morphology who underwent peripheral blood flow cytometric screening for any reason. Circulating CD34+\u2009stem cells and total progenitors were quantified and correlated with clinical characteristics and outcomes.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Patients ultimately diagnosed with aplastic anemia (n\u2009=\u200915) showed significantly decreased circulating progenitors compared with those with cytopenias of alternative causes, whereas patients with infectious, inflammatory, or other presumed reactive conditions often demonstrated larger CD34+\u2009progenitor populations, consistent with preserved or responsive marrow function. Using receiver operating characteristic analysis, the optimal cutoff for %CD34+\u2009progenitors was 0.0124%, which was rounded to 0.01% for clinical interpretability.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>These findings support the potential clinical utility of peripheral blood CD34+\u2009quantitation in the diagnostic workup of pediatric pancytopenia.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/ajcp\/aqag058","type":"journal-article","created":{"date-parts":[[2026,6,10]],"date-time":"2026-06-10T11:52:58Z","timestamp":1781092378000},"source":"Crossref","is-referenced-by-count":0,"title":["Flow cytometric quantitation of CD34+ progenitors in peripheral blood: an adjunct tool for diagnostic evaluation of pancytopenia"],"prefix":"10.1093","volume":"165","author":[{"given":"Lauren","family":"Reiman","sequence":"first","affiliation":[{"name":"Keck School of Medicine, University of Southern California , Los Angeles, CA,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"My H","family":"Vu","sequence":"additional","affiliation":[{"name":"Biostatistics, Informatics, and Data Management Core, Children\u2019s Hospital of Los Angeles , Los Angeles, CA,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Cortez-Bacolot","sequence":"additional","affiliation":[{"name":"Hematopathology, Department of Pathology and Laboratory Medicine, Children\u2019s Hospital Los Angeles , Los Angeles, CA,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Brent L","family":"Wood","sequence":"additional","affiliation":[{"name":"Keck School of Medicine, University of Southern California , Los Angeles, CA,","place":["United States"]},{"name":"Hematopathology, Department of Pathology and Laboratory Medicine, Children\u2019s Hospital Los Angeles , Los Angeles, CA,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6742-6749","authenticated-orcid":false,"given":"Alexandra E","family":"Kovach","sequence":"additional","affiliation":[{"name":"Keck School of Medicine, University of Southern California , Los Angeles, CA,","place":["United States"]},{"name":"Hematopathology, Department of Pathology and Laboratory Medicine, Children\u2019s Hospital Los Angeles , Los Angeles, CA,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2026,6,17]]},"reference":[{"key":"2026061800003026800_aqag058-B1","doi-asserted-by":"publisher","first-page":"1643","DOI":"10.1056\/NEJMra1413485","article-title":"Aplastic anemia","volume":"379","author":"Young","year":"2018","journal-title":"N Engl J 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