{
  "abstract": "Background and Importance Ceftazidime-avibactam-aztreonam is used to treat infections caused by MBL-producing Enterobacteriaceae. Avibactam protects aztreonam from non-MBL β-lactamases (Ambler class A/D). Ceftazidime is included due to the unavailability of aztreonam-avibactam until 2025.Aim and Objectives To evaluate the effectiveness (clinical cure, microbiological eradication, and recurrence), mortality, and outcome predictors in infections treated with ceftazidime-avibactam-aztreonam.Material and Methods Retrospective study of patients with active infection treated with ceftazidime-avibactam-aztreonam (January 2022–April 2025). Sociodemographic, clinical, infection-related, and treatment data were collected. Outcomes included clinical/microbiological cure, 90-day clinical/microbiological recurrence, early (24–48h), 30-day, and intra-hospital mortality. Univariate and multivariate logistic regression analyses were performed. Quantitative data were expressed in mean and SD; qualitative in percentage with 95% CI. Analysis: M365 Copilot.Results Eight-four patients received ceftazidime-avibactam-aztreonam.Abstract 4CPS-113 Table 1Sociodemographic profileMale gender 61.9% (51.2-72.6) Age (years) 70.9 (15.0) Hospital stay (days) 51.8 (45.0) Intensive care unit (ICU) admission 36.9% (26.2-47.6) ICU stay (days) 20.2 (36.4) Abstract 4CPS-113 Table 2Microbiological and infection associated parametersInfection Source:UrinaryRespiratoryAbdominalSkin and Soft TissueEndovascularThoracicUnknown 38.1% (27.4-48.8)21.4% (13.1-31.0)17.9% (9.5-26.2)8.3% (2.4-14.3)6.0% (1.2-11.9)1.2% (0.1-3.6)7.1% (2.4-13.1) Another infection source 13.1% (6.0-20.2) Sepsis 33.3% (23.8–44.1) Polymicrobial infection 45.2% (34.5–56.0) Carbapenemases:OXA-48+NDMVIMOXA-48NDMIMPGESVIM+IMP 57.6% (47.8-67.4)13.0% (6.5-20.7)11,9% (3.3-21.7)8.7% (3.3-15.2)5.5% (1.1-10.9)2.2% (0.1-5.4)1.1% (0.1-3.3) Abstract 4CPS-113 Table 3Treatment-related dataTargeted treatment 84.5% (76.2-91.7) Treatment duration (days) 7.3 (5.0) Multi-antibiotic therapy 39.3% (28.6-50.0) Clinical and microbiological cure was achieved in 82.1% (73.8-90.5) and 56.6% (45.2-66.7) of patients, respectively. 90-day relapse rate was 23.7% (14.5–32.9).Mortality rates: early 4.8% (1.2-9.5), 30-day 21.3% (12.5-30.0) and intra-hospital 32.1% (22.6-42.9).Directed treatment was associated with higher infection cure rates (clinical and/or microbiological) (OR: 4.7; 95% CI: 0.9–25.4; p=0.04) and lower mortality (OR: 0.3; 95% CI: 0.1–1.2; p=0.04), while longer hospital stay correlated with reduced mortality (OR: 0.9; 95% CI: 0.9–0.9; p=0.02).Conclusion and Relevance Ceftazidime-avibactam-aztreonam showed high clinical effectiveness in treating MBL-producing infections, despite moderate microbiological cure, notable relapse and mortality rates. Directed therapy significantly improved outcomes and reduced mortality, and prolonged hospitalisation correlated with lower mortality. These findings support its use while highlighting the need for further research to optimise outcomes and guide individualised treatment strategies.Conflict of Interest No conflict of interest",
  "authors": [
    {
      "affiliations": [
        "Hospital Universitario De La Princesa, Pharmacy, Madrid, Spain"
      ],
      "name": "A Calvo García"
    },
    {
      "affiliations": [
        "Hospital Universitario De La Princesa, Pharmacy, Madrid, Spain"
      ],
      "name": "S Ruiz Garcia"
    },
    {
      "affiliations": [
        "Hospital Universitario De La Princesa, Pharmacy, Madrid, Spain"
      ],
      "name": "A Ibáñez Zurriaga"
    },
    {
      "affiliations": [
        "Hospital Universitario De La Princesa, Pharmacy, Madrid, Spain"
      ],
      "name": "CM Sáez Béjar"
    },
    {
      "affiliations": [
        "Hospital Universitario De La Princesa, Pharmacy, Madrid, Spain"
      ],
      "name": "M Pérez Abánades"
    },
    {
      "affiliations": [
        "Hospital Universitario De La Princesa, Pharmacy, Madrid, Spain"
      ],
      "name": "E Ramírez Herraiz"
    },
    {
      "affiliations": [
        "Hospital Universitario De La Princesa, Pharmacy, Madrid, Spain"
      ],
      "name": "JM Serra López-Matencio"
    },
    {
      "affiliations": [
        "Hospital Universitario De La Princesa, Pharmacy, Madrid, Spain"
      ],
      "name": "L Botica Moros"
    },
    {
      "affiliations": [
        "Hospital Universitario De La Princesa, Pharmacy, Madrid, Spain"
      ],
      "name": "A Aranguren Oyarzabal"
    }
  ],
  "title": "4CPS-113 Ceftazidime-avibactam plus aztreonam in multidrug-resistant bacterial infections: effectiveness, mortality and outcome predictors",
  "uid": "03e99104-6812-5335-92b8-c13a3d93b617"
}