L. C. M. Castelo Branco

Antimicrobial resistance is a global public health threat that has been impacted by the COVID-19 pandemic. The aim of this study was to evaluate the resistance of Acinetobacter spp. isolated from patients with pneumonia in a Brazilian Pre-Amazon region during the pre-pandemic and pandemic periods of COVID-19. Bacterial strains were obtained from tracheal aspiration, sputum and bronchoalveolar lavage for diagnosis and phenotypic characterization. MALD-TOF was used to identify strains. The automated Phoenix and VITEK® 2 Compact system and the disc diffusion method were performed to determine the antimicrobial susceptibility profile. Were analyzed a total of 41,590 samples from patients admitted to hospitals of a Brazilian Pre-Amazon region, from January 2019 to December 2021. Of these, 162 isolates of Acinetobacter spp. were from the pre-pandemic period and 308 from the pandemic COVID-19. A. baumannii was the most prevalent species. Among the samples, 52% were male patients, aged over 60 years, hospitalized in intensive care units. Acinetobacter spp. showed higher rates of resistance to cefepime (79.1%), levofloxacin (77.8%), and ceftazidime (77%) in the pre-pandemic period and during the pandemic to piperacillin (72.4%), imipenem (71.6%) and ciprofloxacin (71.8%). Taken together, the data showed that A. baumannii was the most prevalent species among Acinetobacter spp., being more frequent among elderly patients admitted to the ICU. The strains presented high resistance to most antibiotics tested, mainly carbapenems. In addition, there was an increase in resistance to polymyxin B, which raises an alert since this is a therapeutic choice to treat infections caused by Acinetobacter spp. multidrug resistant.

Healthcare-related infections caused by resistant microorganisms are a severe public health problem and are becoming increasingly prevalent in the hospital environment, especially Pseudomonas aeruginosa. This work aimed to evaluate the resistance profile of Pseudomonas aeruginosa to antimicrobials before the COVID-19 pandemic and during the pandemic period. Bacteria strains were obtained from tracheal aspiration, sputum, and bronchoalveolar lavage for diagnosis and phenotypic characterization. Matrix assisted laser-desorption ionization-time of flight mass spectrometry (MALD-TOF MS) was used to identify strains. Automated Phoenix and VITEK^® 2 Compact system and the disc diffusion method were performed to determine the antimicrobial susceptibility profile. A total of 41,000 medical reports from adult patients with pneumonia were analyzed. Of these, 951 patients were positive for P. aeruginosa, of which 373 were related to the pre-pandemic period and 578 to the pandemic period. Older men (≥60 years) were more prevalent in both periods. P. aeruginosa strains were resistant to imipenem in both periods: 38.8 and 42.5%, respectively, followed by meropenem (34.2 and 39.2%), ciprofloxacin (33.6 and 36.7%), and levofloxacin (34.9 and 43.5%). Intensive care units had the highest percentage of affected patients (62 and 65%) compared with other sectors, with a prevalence of 71% in the public network before COVID-19 and 59% during the pandemic. Our data showed a prevalence of P. aeruginosa in elderly patients in both the pre-pandemic and pandemic periods. In addition, an increase in P. aeruginosa resistance to beta-lactams, quinolones, carbapenems, and cephalosporins was observed during the COVID-19 pandemic compared with the period before the pandemic, especially in ICUs.