{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T05:16:15Z","timestamp":1783574175482,"version":"3.55.0"},"reference-count":22,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T00:00:00Z","timestamp":1783555200000},"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:sec>\n                    <jats:title>Purpose<\/jats:title>\n                    <jats:p>C-reactive protein (CRP) is widely used to guide antibiotic therapy in children; however, a uniform CRP cut-off is commonly applied across all pediatric age groups. This study aimed to investigate whether the CRP response to infection differs by age in children with sepsis.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>This single-center retrospective cross-sectional study included children with a discharge diagnosis of sepsis. Patients were stratified into five age groups according to the recommendations of the International Pediatric Sepsis Consensus Conference: newborn (0 &amp;lt; age \u2264 7 days), neonate (7 &amp;lt; age \u2264 30 days), infant (30 days &amp;lt; age \u2264 2 years), toddler\/preschool (2 &amp;lt; age \u2264 6 years), and school age\/adolescent (6 &amp;lt; age &amp;lt; 18 years). Demographic characteristics, disease severity, vital signs, laboratory parameters, and microbiological test results were collected. Associations between CRP and other parameters were analyzed within and across age groups using nonparametric methods.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      A total of 1,228 patients were included. Newborns and neonates had the highest disease severity (vasoactive infusion: 50.0% and 17.7%; invasive ventilation: 56.5% and 24.2%), yet the lowest CRP levels (median 2.32 mg\/L and 5.09 mg\/L). In contrast, older children had markedly lower disease severity but 5 to 10-fold higher CRP levels. CRP was positively correlated with procalcitonin (PCT) across all age groups (\n                      <jats:italic>P<\/jats:italic>\n                      &amp;lt;\u00a00.01), suggesting preserved responsiveness to infection but a reduced magnitude of CRP elevation in newborns and neonates.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>The CRP response to infection is substantially attenuated in newborns and neonates despite greater clinical severity. This age-dependent phenomenon suggests that a single CRP cut-off is inappropriate for all pediatric age groups. Clinicians should interpret CRP levels in very young children with caution, recognizing that even modest elevations may indicate clinically significant infection.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fimmu.2026.1862403","type":"journal-article","created":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T04:23:56Z","timestamp":1783571036000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Attenuated C-reactive protein response to infection in newborns and neonates: an age-stratified analysis in children with sepsis"],"prefix":"10.3389","volume":"17","author":[{"given":"Zhen-Yu","family":"Yao","sequence":"first","affiliation":[{"name":"School of Basic Medical Sciences, Gansu University of Chinese Medicine","place":["Lanzhou, Gansu, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Li-Ting","family":"Huang","sequence":"additional","affiliation":[{"name":"School of Basic Medical Sciences, Gansu University of Chinese Medicine","place":["Lanzhou, Gansu, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hui-Qiang","family":"Cai","sequence":"additional","affiliation":[{"name":"Xi\u2019an Children\u2019s Hospital & Affiliated Children Hospital of Xi\u2019an Jiaotong University","place":["Xi\u2019an, Shaanxi, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jun","family":"Wen","sequence":"additional","affiliation":[{"name":"Xi\u2019an Children\u2019s Hospital & Affiliated Children Hospital of Xi\u2019an Jiaotong University","place":["Xi\u2019an, Shaanxi, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shang-Rong","family":"Ji","sequence":"additional","affiliation":[{"name":"MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University","place":["Lanzhou, Gansu, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jian-Min","family":"Lv","sequence":"additional","affiliation":[{"name":"Rehabilitation Science Institute, Shaanxi Provincial Rehabilitation Hospital","place":["Xi\u2019an, Shaanxi, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,7,9]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.1001\/jama.2016.0287","article-title":"The third international consensus definitions for sepsis and septic shock (Sepsis-3)","volume":"315","author":"Singer","year":"2016","journal-title":"JAMA"},{"key":"B2","doi-asserted-by":"publisher","first-page":"47","DOI":"10.1186\/s40560-017-0240-1","article-title":"Update on pediatric sepsis: a review","volume":"5","author":"Kawasaki","year":"2017","journal-title":"J Intensive Care"},{"key":"B3","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMoa1803185","article-title":"C-reactive protein testing to guide 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