{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,17]],"date-time":"2026-10-17T05:53:03Z","timestamp":1792216383657,"version":"4.4.0"},"reference-count":42,"publisher":"Wiley","issue":"9","license":[{"start":{"date-parts":[[2024,4,25]],"date-time":"2024-04-25T00:00:00Z","timestamp":1714003200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"funder":[{"DOI":"10.13039\/100000102","name":"Health Resources and Services Administration","doi-asserted-by":"publisher","award":["H34MCO8509, R01HD085233"],"award-info":[{"award-number":["H34MCO8509, R01HD085233"]}],"id":[{"id":"10.13039\/100000102","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100009633","name":"Eunice Kennedy Shriver National Institute of Child Health and Human Development","doi-asserted-by":"publisher","award":["R01HD062477"],"award-info":[{"award-number":["R01HD062477"]}],"id":[{"id":"10.13039\/100009633","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Academic Emergency Medicine"],"published-print":{"date-parts":[[2024,9]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec><jats:title>Background and objective<\/jats:title><jats:p>Serum procalcitonin (<jats:styled-content style=\"fixed-case\">PCT<\/jats:styled-content>) is a highly accurate biomarker for stratifying the risk of invasive bacterial infections (<jats:styled-content style=\"fixed-case\">IBIs<\/jats:styled-content>) in febrile infants \u226460\u2009days old. However, <jats:styled-content style=\"fixed-case\">PCT<\/jats:styled-content> is unavailable in some settings. We explored the association of leukopenia and neutropenia with <jats:styled-content style=\"fixed-case\">IBIs<\/jats:styled-content> in non\u2013critically ill febrile infants \u226460\u2009days old, with and without <jats:styled-content style=\"fixed-case\">PCT<\/jats:styled-content>.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>We conducted a secondary analysis of a prospective observational cohort consisting of 7407 non\u2013critically ill infants \u226460\u2009days old with temperatures \u226538\u00b0C. We focused on the risk of IBIs in patients with leukopenia (white blood cell [WBC] count &lt;5000 cells\/\u03bcL) or neutropenia (absolute neutrophil count [ANC] &lt;1000 cells\/\u03bcL), categorized to extremes of lower values, and the impact of PCT on these associations. Multiple logistic regression was used to identify independent predictors of IBIs.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>Final analysis included 6865 infants with complete data; 45% (3098) had PCT data available. Of the 6865, a total of 111 (1.6%) had bacteremia without bacterial meningitis, 18 (0.3%) had bacterial meningitis without bacteremia, and 19 (0.3%) had both bacteremia and bacterial meningitis. IBI was present in four of 20 (20%) infants with WBC counts \u22642500 cells\/\u03bcL and four of 311 (1.3%) with ANC \u22641000 cells\/\u03bcL. In multivariable logistic regression analysis not including PCT, a WBC count \u22642500 cells\/\u03bcL was significantly associated with IBI (OR 13.48, 95% CI 2.92\u201345.35). However, no patients with leukopenia or neutropenia and PCT \u22640.5\u2009ng\/mL had IBIs.<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusions<\/jats:title><jats:p>Leukopenia \u22642500 cells\/\u03bcL in febrile infants \u226460\u2009days old is associated with IBIs. However, in the presence of normal PCT levels, no patients with leukopenia had IBIs. While this suggests leukopenia \u22642500 cells\/\u03bcL is a risk factor for IBIs in non\u2013critically ill young febrile infants only when PCT is unavailable or elevated, the overall low frequency of leukopenia in this cohort warrants caution in interpretation, with future validation required.<\/jats:p><\/jats:sec>","DOI":"10.1111\/acem.14921","type":"journal-article","created":{"date-parts":[[2024,4,25]],"date-time":"2024-04-25T11:50:13Z","timestamp":1714045813000},"page":"903-914","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Leukopenia, neutropenia, and procalcitonin levels in young febrile infants with invasive bacterial infections"],"prefix":"10.1111","volume":"31","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3206-4645","authenticated-orcid":false,"given":"Andrew T.","family":"Krack","sequence":"first","affiliation":[{"name":"Department of Pediatrics Children's Hospital Colorado  Aurora Colorado USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michelle","family":"Eckerle","sequence":"additional","affiliation":[{"name":"Cincinnati Children's Hospital Medical Center and the University of Cincinnati College of Medicine  Cincinnati Ohio USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4278-3560","authenticated-orcid":false,"given":"Prashant","family":"Mahajan","sequence":"additional","affiliation":[{"name":"University of Michigan Medical School  Ann Arbor Michigan USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Octavio","family":"Ramilo","sequence":"additional","affiliation":[{"name":"St. Jude Children\u2019s Research Hospital  Memphis TN"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John M.","family":"VanBuren","sequence":"additional","affiliation":[{"name":"University of Utah  Salt Lake City Utah USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Russell K.","family":"Banks","sequence":"additional","affiliation":[{"name":"University of Utah  Salt Lake City Utah USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"T. Charles","family":"Casper","sequence":"additional","affiliation":[{"name":"University of Utah  Salt Lake City Utah USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7379-7012","authenticated-orcid":false,"given":"David","family":"Schnadower","sequence":"additional","affiliation":[{"name":"Cincinnati Children's Hospital Medical Center and the University of Cincinnati College of Medicine  Cincinnati Ohio USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7854-4943","authenticated-orcid":false,"given":"Nathan","family":"Kuppermann","sequence":"additional","affiliation":[{"name":"University of California Davis, School of Medicine  Sacramento California USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"name":"for the Febrile Infant Working Group of the Pediatric Emergency Care Applied Research Network (PECARN)","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2024,4,25]]},"reference":[{"key":"e_1_2_11_2_1","doi-asserted-by":"publisher","DOI":"10.5811\/westjem.2020.8.47455"},{"key":"e_1_2_11_3_1","doi-asserted-by":"publisher","DOI":"10.1542\/peds.2018-3604"},{"key":"e_1_2_11_4_1","doi-asserted-by":"publisher","DOI":"10.1542\/peds.2015-4381"},{"key":"e_1_2_11_5_1","doi-asserted-by":"publisher","DOI":"10.1001\/jamapediatrics.2018.5501"},{"key":"e_1_2_11_6_1","doi-asserted-by":"publisher","DOI":"10.1001\/jama.2016.9207"},{"key":"e_1_2_11_7_1","doi-asserted-by":"publisher","DOI":"10.1136\/emermed-2013-202449"},{"key":"e_1_2_11_8_1","doi-asserted-by":"publisher","DOI":"10.1542\/peds.2019-4096"},{"key":"e_1_2_11_9_1","doi-asserted-by":"publisher","DOI":"10.1542\/peds.108.2.311"},{"key":"e_1_2_11_10_1","doi-asserted-by":"publisher","DOI":"10.1056\/NEJM199311113292001"},{"key":"e_1_2_11_11_1","doi-asserted-by":"publisher","DOI":"10.1016\/S0022-3476(05)80591-8"},{"key":"e_1_2_11_12_1","doi-asserted-by":"publisher","DOI":"10.1016\/S0022-3476(85)80175-X"},{"key":"e_1_2_11_13_1","doi-asserted-by":"publisher","DOI":"10.1542\/peds.94.3.390"},{"key":"e_1_2_11_14_1","doi-asserted-by":"publisher","DOI":"10.1001\/jamapediatrics.2017.2927"},{"key":"e_1_2_11_15_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.jemermed.2019.06.028"},{"key":"e_1_2_11_16_1","doi-asserted-by":"publisher","DOI":"10.1542\/peds.140.1MA.15"},{"key":"e_1_2_11_17_1","doi-asserted-by":"publisher","DOI":"10.1542\/peds.108.4.866"},{"key":"e_1_2_11_18_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.jemermed.2018.04.019"},{"key":"e_1_2_11_19_1","doi-asserted-by":"publisher","DOI":"10.1542\/peds.2013-1759"},{"key":"e_1_2_11_20_1","doi-asserted-by":"publisher","DOI":"10.1542\/peds.2011-1546"},{"key":"e_1_2_11_21_1","doi-asserted-by":"publisher","DOI":"10.1097\/INF.0000000000000225"},{"key":"e_1_2_11_22_1","doi-asserted-by":"publisher","DOI":"10.1097\/01.inf.0000207485.39112.bf"},{"key":"e_1_2_11_23_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.annemergmed.2017.07.488"},{"key":"e_1_2_11_24_1","doi-asserted-by":"publisher","DOI":"10.1001\/jamanetworkopen.2019.0874"},{"key":"e_1_2_11_25_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.jemermed.2019.03.003"},{"key":"e_1_2_11_26_1","doi-asserted-by":"publisher","DOI":"10.1542\/peds.2011-3575"},{"key":"e_1_2_11_27_1","doi-asserted-by":"publisher","DOI":"10.1542\/peds.2007-3503"},{"key":"e_1_2_11_28_1","doi-asserted-by":"publisher","DOI":"10.1001\/jamapediatrics.2015.3210"},{"key":"e_1_2_11_29_1","doi-asserted-by":"publisher","DOI":"10.1542\/peds.2021-052228"},{"key":"e_1_2_11_30_1","doi-asserted-by":"publisher","DOI":"10.1097\/INF.0000000000000919"},{"key":"e_1_2_11_31_1","doi-asserted-by":"publisher","DOI":"10.1111\/ijlh.13306"},{"key":"e_1_2_11_32_1","doi-asserted-by":"publisher","DOI":"10.1182\/asheducation.V2012.1.174.3798251"},{"key":"e_1_2_11_33_1","doi-asserted-by":"publisher","DOI":"10.1373\/clinchem.2015.239731"},{"key":"e_1_2_11_34_1","doi-asserted-by":"publisher","DOI":"10.1197\/j.aem.2004.06.012"},{"key":"e_1_2_11_35_1","doi-asserted-by":"publisher","DOI":"10.1097\/INF.0b013e3182337ddb"},{"key":"e_1_2_11_36_1","doi-asserted-by":"publisher","DOI":"10.1067\/mem.2003.299"},{"key":"e_1_2_11_37_1","doi-asserted-by":"publisher","DOI":"10.3390\/v13020301"},{"key":"e_1_2_11_38_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.jpeds.2018.07.073"},{"key":"e_1_2_11_39_1","doi-asserted-by":"publisher","DOI":"10.1542\/peds.2017-2384"},{"key":"e_1_2_11_40_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.pedneo.2020.08.004"},{"key":"e_1_2_11_41_1","doi-asserted-by":"publisher","DOI":"10.1111\/acem.13489"},{"key":"e_1_2_11_42_1","doi-asserted-by":"publisher","DOI":"10.1513\/AnnalsATS.201704-306RL"},{"key":"e_1_2_11_43_1","doi-asserted-by":"publisher","DOI":"10.1542\/peds.2017-1688"}],"container-title":["Academic Emergency Medicine"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/acem.14921","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,11,19]],"date-time":"2024-11-19T09:34:28Z","timestamp":1732008868000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1111\/acem.14921"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,4,25]]},"references-count":42,"journal-issue":{"issue":"9","published-print":{"date-parts":[[2024,9]]}},"alternative-id":["10.1111\/acem.14921"],"URL":"https:\/\/doi.org\/10.1111\/acem.14921","archive":["Portico"],"relation":{},"ISSN":["1069-6563","1553-2712"],"issn-type":[{"value":"1069-6563","type":"print"},{"value":"1553-2712","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,4,25]]},"assertion":[{"value":"2023-09-15","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2024-03-25","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2024-04-25","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}