Antimicrobial resistance of gram-negative bacilli in ventilator-associated pneumonia in an ICU in Itauguá, 2022-2024
DOI:
https://doi.org/10.18004/Keywords:
Ventilator-Associated Pneumonia, Multidrug-Resistant Bacteria, Gram-Negative BacteriaAbstract
Introduction: Ventilator-associated pneumonia is the most frequent nosocomial infection in
patients undergoing respiratory assistance, representing a significant cause of morbidity and
mortality in critical care units. Its occurrence is related to multiple clinical and microbiological
factors, including oropharyngeal colonization, biofilm formation on respiratory devices, and the
selection of highly resistant pathogens within the hospital environment. Objective: To describe
the etiological agents and their antimicrobial resistance patterns in an adult intensive care
unit at the Hospital Nacional de Itauguá, Paraguay, during the 2022-2024 period. Materials
and Methods: An observational, descriptive, cross-sectional, and retrospective study was
conducted. It included 244 adult patients with a confirmed diagnosis through tracheal aspirate or
bronchoalveolar lavage cultures. Demographic variables, type of pneumonia, and microbiological
profiles were analyzed. Results: The mean age was 53 years, with a predominance of males
(72%). Late-onset pneumonia was the most frequent form (58%). The predominant isolated
agents were the Acinetobacter baumannii complex (29.5%), Pseudomonas aeruginosa (16.8%),
and Klebsiella pneumoniae (9.0%). Polymicrobial etiology was observed in 27.9% of cases.
Additionally, 25% of the isolates showed multidrug resistance, while 12.7% exhibited special
resistance mechanisms, notably metallo-β-lactamases and carbapenemases. Conclusion:
Gram-negative bacilli remain the primary causative agents and show a high prevalence of
resistance. This highlights the need to optimize empirical treatment, reinforce microbiological
surveillance, and strengthen institutional programs for the rational use of antimicrobials.
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