{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,28]],"date-time":"2026-05-28T07:03:15Z","timestamp":1779951795664,"version":"3.53.1"},"reference-count":25,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,5,28]],"date-time":"2026-05-28T00:00:00Z","timestamp":1779926400000},"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. Pharmacol."],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>\n                      Multidrug-resistant\n                      <jats:italic>Pseudomonas aeruginosa<\/jats:italic>\n                      (MDR-PA) infection in preterm infants is associated with high mortality, and treatment options are limited. Ceftazidime-avibactam (CAZ-AVI) is a novel \u03b2-lactam\/\u03b2-lactamase inhibitor combination, but data on its pharmacokinetic\/pharmacodynamic (PK\/PD)-guided use in preterm infants are scarce.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We report a 33-week preterm infant with congenital chylothorax\/ascites complicated by MDR-PA infection. Antimicrobial susceptibility testing revealed resistance to meropenem (MIC &amp;gt; 16\u00a0\u03bcg\/mL) and ceftazidime (MIC &amp;gt; 32\u00a0\u03bcg\/mL) but sensitivity to CAZ-AVI (MIC = 4\u00a0\u03bcg\/mL). A PK\/PD-guided regimen of CAZ-AVI 40\u201350\u00a0mg\/kg (based on the ceftazidime component, every 8\u00a0h, prolonged infusion \u22652\u00a0h) was administered to achieve a %fT &amp;gt; MIC target of \u2265 70%, considering the preterm infant\u2019s immature renal function and increased volume of distribution.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>After initiation of CAZ-AVI, high-sensitivity C-reactive protein (hs-CRP) decreased from 30.00\u00a0mg\/L to 7.21\u00a0mg\/L within 5\u00a0days and normalized by day 7. Thoracic and abdominal drainage volumes declined significantly. The infant was successfully weaned from mechanical ventilation and discharged with clinical recovery. No drug-related adverse events were observed.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>PK\/PD-based individualized CAZ-AVI therapy achieved a favorable clinical outcome in this preterm infant with MDR-PA infection. A dosing strategy targeting %fT&amp;gt; MIC \u2265 70% appears feasible and safe in neonates. This case provides quantitative PK\/PD support for CAZ-AVI dosing in preterm infants, a population with limited existing evidence.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fphar.2026.1849617","type":"journal-article","created":{"date-parts":[[2026,5,28]],"date-time":"2026-05-28T06:21:05Z","timestamp":1779949265000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["PK\/PD-guided ceftazidime\u2013avibactam dosing for multidrug-resistant Pseudomonas aeruginosa infection in a preterm infant with chylothorax and ascites: a case report"],"prefix":"10.3389","volume":"17","author":[{"given":"Wenhao","family":"Yuan","sequence":"first","affiliation":[{"name":"Department of Neonatology, Wuhan Children\u2019s Hospital (Wuhan Maternal and Child Healthcare Hospital), Tongji Medical College, Huazhong University of Science and Technology","place":["Wuhan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaotan","family":"Zhao","sequence":"additional","affiliation":[{"name":"Department of Neonatology, Wuhan Children\u2019s Hospital (Wuhan Maternal and Child Healthcare Hospital), Tongji Medical College, Huazhong University of Science and Technology","place":["Wuhan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaoyan","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Neonatology, Wuhan Children\u2019s Hospital (Wuhan Maternal and Child Healthcare Hospital), Tongji Medical College, Huazhong University of Science and Technology","place":["Wuhan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xuwei","family":"Tao","sequence":"additional","affiliation":[{"name":"Department of Neonatology, Wuhan Children\u2019s Hospital (Wuhan Maternal and Child Healthcare Hospital), Tongji Medical College, Huazhong University of Science and Technology","place":["Wuhan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lingkong","family":"Zeng","sequence":"additional","affiliation":[{"name":"Department of Neonatology, Wuhan Children\u2019s Hospital (Wuhan Maternal and Child Healthcare Hospital), Tongji Medical College, Huazhong University of Science and Technology","place":["Wuhan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,5,28]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"192","DOI":"10.5863\/1551-6776-27.2.192","article-title":"Intravenous ceftazidime-avibactam in extremely premature neonates with carbapenem-resistant enterobacteriaceae: two case reports","volume":"27","author":"Asfour","year":"2022","journal-title":"J. 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