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Currently, a global health crisis is being caused by microbial resistance, in which Acinetobacter baumannii plays a crucial role, being considered the highest-priority microorganism by the World Health Organization (WHO) for discovering new antibiotics. As a result, phytochemicals have emerged as a potential alternative to combat resistant strains, since they can exert antimicrobial activity through various mechanisms and, at the same time, represent a more natural and safe option. This study analyzes the antimicrobial effects of guava leaf extract in ten clinical isolates of extensively drug-resistant (XDR) A. baumannii, using the agar diffusion technique and the microdilution method to determine the minimum inhibitory concentrations (MICs). Additionally, possible improvements in antimicrobial activity after the purification of polyphenolic compounds and potential synergy with the antibiotic gentamicin are examined in this research. Moreover, the effect of the plant extract in cell line A549 derived from lung tissue was also evaluated. The extract exhibited antimicrobial activity against all the strains studied, and the purification of polyphenols along with the combination with gentamicin improved the extract activity. The presence of the plant extract induced morphological changes in the lung cells after 24 h of exposure. Therefore, Psidium guajava L. leaf extract is a potential antimicrobial agent.

Pseudomonas aeruginosa is a leading cause of healthcare-associated infections, which are related to substantial morbidity and mortality. The incidence of Plasmid-Mediated Quinolone Resistance (PMQR) determinants has been previously reported in this bacterium. However, there is limited information regarding the presence of PMQR and carbapenemase-encoding genes simultaneously. This study aims to analyze the prevalence of these determinants on P. aeruginosa strain isolated from clinical patients in the State of Aguascalientes, Mexico. Fifty-two P. aeruginosa isolates from nosocomial patients were collected from Centenario Hospital Miguel Hidalgo. This is a retrospective observational study conducted at a single center. Antibiotic susceptibility was tested using the Vitek-2 system. Only carbapenem-resistant isolates were included in this study. Carbapenemase-encoding genes and PMQR determinants were screened by polymerase chain reaction (PCR). Resistance rates of 100% were found on tigecycline and ceftriaxone. Of the 52 isolates, 34.6% were positive for the qnr genes, 46.2% for the oqxA gene, and 25% for the aac-(6′)-lb gene. The most frequent carbapenemase genes found in the samples were blaOXA-51 (42.3%), blaOXA-1 (15.4%), and blaVIM (15.4%). blaOXA-51 co-carrying oqxA was detected in 21.1% of the isolates, blaOXA-51 co-carrying aac-(6’)-lb in 11.5%, blaVIM co-carrying aac-(6′)-lb in 3.8%, and blaKPC co-carrying oqxA in 5.8%. Systematic surveillance to detect carbapenemase-encoding genes and PMQR determinants, and rational prescription using the last-line drugs could help in preventing the dissemination of multidrug-resistant determinants.

Uropathogenic Escherichia coli (UPEC) strains are among the leading causes of urinary tract infections (UTIs) worldwide. They can colonize the urinary tract and form biofilms that allow bacteria to survive and persist, causing relapses of infections and life-threatening sequelae. Here, we analyzed biofilm production, antimicrobial susceptibility, virulence factors, and phylogenetic groups in 74 E. coli isolated from diagnosed patients with UTIs to describe their microbiological features and ascertain their relationship with biofilm capabilities. High levels of ceftazidime resistance are present in hospital-acquired UTIs. Isolates of multidrug resistance strains (p = 0.0017) and the yfcV gene (p = 0.0193) were higher in male patients. All the strains tested were able to form biofilms. Significant differences were found among higher optical densities (ODs) and antibiotic resistance to cefazolin (p = 0.0395), ceftazidime (p = 0.0302), and cefepime (p = 0.0420). Overall, the presence of fimH and papC coincided with strong biofilm formation by UPEC. Type 1 fimbriae (p = 0.0349), curli (p = 0.0477), and cellulose (p = 0.0253) production was significantly higher among strong biofilm formation. Our results indicated that high antibiotic resistance may be related to male infections as well as strong and moderate biofilm production. The ability of E. coli strains to produce biofilm is important for controlling urinary tract infections.

During the first year of the COVID-19 pandemic, unauthorized drugs were widely used. Ivermectin and hydroxychloroquine are drugs that inhibit viral replication in vitro and that have been used in several medical centers. This clinical trial analyzes their efficacy in hospitalized patients with moderate COVID-19. Methods: This a controlled, clinical, randomized, double-blind trial that included hospitalized patients with COVID-19-induced pneumonia, without severe respiratory failure. Patients were randomized to one of three groups: Group 1—hydroxychloroquine, 400 mg every 12 h on the first day and, subsequently, 200 mg every 12 h for 4 days; Group 2—ivermectin, 12 mg or 18 mg, according to patient weight; and Group 3—placebo. At inclusion, blood samples for arterial blood gases and biochemical markers were obtained. The primary outcome was established as the length of stay due to patient improvement and the rate of respiratory deterioration or death. Results: During the month of August 2020, the admission of patients requiring hospitalization mostly encompassed cases with severe respiratory failure, so we ended the recruitment process and analyzed the data that was available at the time. One hundred and six (106) patients with an average age of 53 yrs (±16.9) were included, with a greater proportion of males (n = 66, 62.2%). Seventy-two percent (72%) (n = 76) had an associated comorbidity. Ninety percent (90%) of patients were discharged due to improvement (n = 96). The average duration of hospitalization was 6 days (IQR, 3–10). No difference in hospitalization duration was found between the treatment groups (Group1: 7 vs. Group 2: 6 vs. Group 3: 5, p = 0.43) nor in respiratory deterioration or death (Group 1: 18% vs. Group 2: 22.2% vs. Group 3: 24.3%, p = 0.83). Conclusions: In non-critical hospitalized patients with COVID-19 pneumonia, neither ivermectin nor hydroxychloroquine decreases the number of in-hospital days, respiratory deterioration, or deaths.