Carbapenem-resistant Acinetobacter baumannii infections: description of a cohort of hospitalized elderly patients
DOI:
https://doi.org/10.52226/sea2b514Keywords:
Acinetobacter Baumannii. Antimicrobial resistance. Older adultAbstract
Carbapenem-resistant Acinetobacter baumannii (ABA-RCB) infections represent a critical global threat due to their limited therapeutic options. This observational, analytical and retrospective study (2021-2024) evaluated the clinical, epidemiological profile and outcome of 57 patients with confirmed ABA-RCB infection in a second level hospital in Rosario, Argentina. The mean age was 76.2 years (54% women). The main risk factors identified were previous use of antimicrobials (72%) and recent surgeries (47%). The most prevalent infections were pneumonia (54.39%) and those associated with prosthetic material (19.28%). Targeted treatment was predominantly performed as monotherapy (96.49%), using colistin in 79% of cases. A statistically significant association was recorded between antimicrobial treatment and worsening renal function (p=0.001). 75.44% of patients required care in the intensive care unit and overall mortality reached 61.40%. No statistically significant relationship was found between mortality and comorbidities, the infectious focus or the treatment regimen used. In conclusion, ABA-RCB infections in this population of older adults presented extremely high morbidity and mortality. Current clinical management is severely limited by the lack of access to new state-of-the-art antimicrobials, forcing the use of colistin monotherapies that carry high nephrotoxicity. These results underscore the urgent need for novel targeted therapies and optimization of early clinical suspicion.
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