{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,29]],"date-time":"2026-05-29T05:04:38Z","timestamp":1780031078829,"version":"3.53.1"},"reference-count":15,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,5,29]],"date-time":"2026-05-29T00:00:00Z","timestamp":1780012800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Immunol."],"abstract":"<jats:p>\n                    Congenital neutropenia refers to a group of rare inherited disorders in which neutrophil development or release is disrupted, predisposing affected children to frequent infections. Among the genes involved,\n                    <jats:italic>CXCR2<\/jats:italic>\n                    loss-of-function variants have recently been recognized as a distinct cause of the disease. Here, we report a 12-month-old Chinese boy, who presented with repeated febrile respiratory illnesses and intermittent neutropenia since the age of 10 months. During each episode of the child\u2019s viral infection, absolute neutrophil counts ranged between 0.13 and 0.44 \u00d710\n                    <jats:sup>9<\/jats:sup>\n                    \/L, while hemoglobin and platelet values remained within the expected range. Lymphocyte subsets and immunoglobulin levels were normal. Whole-exome sequencing revealed two novel\n                    <jats:italic>CXCR2<\/jats:italic>\n                    variants: a frameshift mutation (c.665delT, p.Val222GlyfsTer4) from his mother and a missense mutation (c.748A&amp;gt;C, p.Met250Leu) from his father. He required intermittent courses of granulocyte colony-stimulating factor and broad-spectrum antibiotics during neutropenic fever episodes. This case expands the mutational and phenotypic spectrum of\n                    <jats:italic>CXCR2<\/jats:italic>\n                    -related congenital neutropenia and highlights the value of genetic testing for infants with unexplained chronic neutropenia and recurrent infections.\n                  <\/jats:p>","DOI":"10.3389\/fimmu.2026.1845797","type":"journal-article","created":{"date-parts":[[2026,5,29]],"date-time":"2026-05-29T04:44:20Z","timestamp":1780029860000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Case Report: Novel CXCR2 compound heterozygous variants in an infant with neutropenia"],"prefix":"10.3389","volume":"17","author":[{"given":"Hua","family":"Liu","sequence":"first","affiliation":[{"name":"Department of Pediatrics, Beijing United Family Women\u2019s and Children\u2019s Hospital","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yinzhu","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Beijing United Family Women\u2019s and Children\u2019s Hospital","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiao","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Beijing United Family Women\u2019s and Children\u2019s Hospital","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiayue","family":"Qin","sequence":"additional","affiliation":[{"name":"Department of Medical Affairs, Acornmed Biotechnology Co., Ltd.","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chunyi","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Beijing United Family Women\u2019s and Children\u2019s Hospital","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Junjin","family":"Huang","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Beijing United Family Women\u2019s and Children\u2019s Hospital","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Danyang","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Hematology, Beijing Lu He Hospital","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hebing","family":"Zhou","sequence":"additional","affiliation":[{"name":"Department of Hematology, Beijing Lu He Hospital","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ming","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Beijing United Family Women\u2019s and Children\u2019s Hospital","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yan","family":"Yue","sequence":"additional","affiliation":[{"name":"Department of Hematology, Beijing Lu He Hospital","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,5,29]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"586","DOI":"10.1136\/jcp-2022-208686","article-title":"Discerning clinicopathological features of congenital neutropenia syndromes: an approach to diagnostically challenging differential diagnoses","volume":"77","author":"Parisi","year":"2024","journal-title":"J Clin Pathol"},{"key":"B2","doi-asserted-by":"publisher","DOI":"10.1172\/jci41649","article-title":"CXCR2 and CXCR4 antagonistically regulate neutrophil trafficking from murine bone marrow","volume":"120","author":"Eash","year":"2010","journal-title":"J Clin 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