{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T06:27:02Z","timestamp":1786688822245,"version":"build-2736575974"},"reference-count":28,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T00:00:00Z","timestamp":1786665600000},"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:p>\n                    Treating carbapenem-resistant\n                    <jats:italic>Klebsiella pneumoniae<\/jats:italic>\n                    (CRKP) is challenging, particularly when resistance is mediated by New Delhi metallo-\u03b2-lactamase (NDM). Clinical experience with fixed-combination aztreonam\u2013avibactam (ATM\u2013AVI) in young infants remains extremely limited. Here, we report a case of a 2-month-old boy who underwent emergency laparotomy for intestinal obstruction owing to small bowel volvulus with segmental necrosis, followed by bowel resection and reanastomosis. His postoperative course was complicated by respiratory failure, coagulopathy, septic shock, recurrent abdominal distension, and massive ascites. Blood cultures were negative, whereas metagenomic next-generation sequencing of blood detected\n                    <jats:italic>K. pneumoniae<\/jats:italic>\n                    and\n                    <jats:italic>Enterococcus faecium<\/jats:italic>\n                    . Owing to the worsening of his condition, diagnostic paracentesis and repeat laparotomy were performed, revealing an anastomotic leak. Intraoperative pus culture yielded\n                    <jats:italic>bla<\/jats:italic>\n                    <jats:sub>\n                      <jats:italic>NDM<\/jats:italic>\n                    <\/jats:sub>\n                    -positive CRKP. The isolate was resistant to carbapenems and ceftazidime\u2013AVI but was susceptible to ATM\u2013AVI, with a minimum inhibitory concentration of \u22644\u00a0mg\/L. ATM\u2013AVI was administered at 30\u00a0mg\/kg every 8\u00a0h, based on the aztreonam component, for 14\u00a0days; linezolid and fluconazole were co-administered as part of the broader anti-infective regimen. The combination of definitive surgical source control, targeted antimicrobial therapy, and comprehensive intensive care successfully controlled the infection and stabilized his hemodynamics. The patient defervesced within 24\u00a0h of the first ATM\u2013AVI dose. Inflammatory markers declined rapidly, allowing safe extubation. Follow-up abdominal cultures remained negative. No hepatic or renal toxicity was observed during treatment. This case suggests that, when combined with adequate surgical source control, ATM\u2013AVI may represent a valuable mechanism- and susceptibility-guided pharmacological component in a multidisciplinary treatment paradigm for severe\n                    <jats:italic>bla<\/jats:italic>\n                    <jats:sub>\n                      <jats:italic>NDM<\/jats:italic>\n                    <\/jats:sub>\n                    -positive CRKP infections in selected infants.\n                  <\/jats:p>","DOI":"10.3389\/fphar.2026.1897083","type":"journal-article","created":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T05:32:20Z","timestamp":1786685540000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Aztreonam\u2013avibactam therapy following surgical source control for blaNDM-positive carbapenem-resistant Klebsiella pneumoniae intra-abdominal infection in an infant: a case report"],"prefix":"10.3389","volume":"17","author":[{"given":"Jie","family":"Liu","sequence":"first","affiliation":[{"name":"Pediatric Intensive Care Unit, Department of Pediatrics, West China Second University Hospital, Sichuan University","place":["Chengdu, Sichuan, China"]},{"name":"Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education","place":["Chengdu, Sichuan, China"]},{"name":"NHC Key Laboratory of Chronobiology (Sichuan University), Ministry of Education","place":["Chengdu, Sichuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaoli","family":"He","sequence":"additional","affiliation":[{"name":"Pediatric Intensive Care Unit, Department of Pediatrics, West China Second University Hospital, Sichuan University","place":["Chengdu, Sichuan, China"]},{"name":"Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education","place":["Chengdu, Sichuan, China"]},{"name":"NHC Key Laboratory of Chronobiology (Sichuan University), Ministry of Education","place":["Chengdu, Sichuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wanlin","family":"Zhao","sequence":"additional","affiliation":[{"name":"Pediatric Intensive Care Unit, Department of Pediatrics, West China Second University Hospital, Sichuan University","place":["Chengdu, Sichuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lijia","family":"Du","sequence":"additional","affiliation":[{"name":"Pediatric Intensive Care Unit, Department of Pediatrics, West China Second University Hospital, Sichuan University","place":["Chengdu, Sichuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lina","family":"Qiao","sequence":"additional","affiliation":[{"name":"Pediatric Intensive Care Unit, Department of Pediatrics, West China Second University Hospital, Sichuan University","place":["Chengdu, Sichuan, China"]},{"name":"Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education","place":["Chengdu, Sichuan, China"]},{"name":"NHC Key Laboratory of Chronobiology (Sichuan University), Ministry of Education","place":["Chengdu, Sichuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lu","family":"Qing","sequence":"additional","affiliation":[{"name":"Pediatric Intensive Care Unit, Department of Pediatrics, West China Second University Hospital, Sichuan University","place":["Chengdu, Sichuan, China"]},{"name":"Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education","place":["Chengdu, Sichuan, China"]},{"name":"NHC Key Laboratory of Chronobiology (Sichuan University), Ministry of Education","place":["Chengdu, Sichuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,8,14]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"927","DOI":"10.1002\/phar.4629","article-title":"Aztreonam-avibactam: the dynamic duo against multidrug-resistant gram-negative pathogens","volume":"44","author":"Al Musawa","year":"2024","journal-title":"Pharmacotherapy"},{"key":"B2","doi-asserted-by":"publisher","first-page":"3000605251353486","DOI":"10.1177\/03000605251353486","article-title":"Successful dual therapy of aztreonam and ceftazidime-avibactam for multidrug-resistant Stenotrophomonas maltophilia infection in a preterm neonate: a life-saving approach","volume":"53","author":"Alghamdi","year":"2025","journal-title":"J. Int. Med. Res."},{"key":"B3","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. Pediatr. Pharmacol. Ther."},{"key":"B4","doi-asserted-by":"publisher","first-page":"310","DOI":"10.1007\/s12098-022-04468-7","article-title":"Cefiderocol as salvage therapy for carbapenem-resistant Klebsiella pneumoniae sepsis in an extremely preterm neonate","volume":"90","author":"Bawankule","year":"2023","journal-title":"Indian J. Pediatr."},{"key":"B5","doi-asserted-by":"publisher","first-page":"piaf028","DOI":"10.1093\/jpids\/piaf028","article-title":"Pharmacokinetics and safety of ceftazidime-avibactam in neonates and young infants: a phase 2a, multicenter prospective trial","volume":"14","author":"Bradley","year":"2025","journal-title":"J. Pediatr. Infect. 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