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Background Antibiotics significantly increased life expectancy and decreased mortality rates due to infections. However, this trend is starting to fade with the rise of multidrug-resistant organisms (MDR); these strains are becoming a global burden on healthcare and the economy. The dramatic increase and spread of carbapenem-resistant gram-negative bacteria (CRGNB) has become a serious global public health concern. In this retrospective cross-sectional study, we aimed to estimate the rates of gram-negative bacteremia in five tertiary care hospitals in different geographical locations in Saudi Arabia for five years. Methods A retrospective cross-sectional study was conducted in five tertiary care hospitals in Saudi Arabia among patients with bacteremia due to CRGNB. Electronic medical records were used to retrieve data regarding patient demographics and antimicrobial susceptibility testing (AST) over five years between January 2016 and December 2020. Patients with positive blood cultures for carbapenem-resistant Escherichia (E.) coli, Klebsiella (K.) pneumonia, Pseudomonas (P.) aeruginosa, and Acinetobacter (A.) baumannii comprise the final study population. Results This retrospective multicentric study was conducted between 2016 and 2020 in five tertiary care hospitals across five cities in Saudi Arabia. E. coli (n=2190, 38.03%), K. pneumoniae (n=2154, 37.41%), P. aeruginosa (n = 918, 15.94%), and A. baumannii (n=496, 8.61%) constitute the 5758 gram-negative bacteria isolates. E. coli was the most frequently identified species in Riyadh, AlAhsa, Dammam, and Madinah (40%, 46.50%, 61.67%, and 43.66%, respectively), with a p-value of (p<0.001), except in Jeddah, where K. pneumoniae was the most prevalent (42%). The mean age of patients across Riyadh, AlAhsa, Dammam, and Madinah was 62.2 years (± 4.24). In contrast to Jeddah, where the majority of isolates (702; 41.8%) belonged to the adult age group. Most isolates were from male patients (3045; 52.9%), compared to 2713 (47.1%) from female patients. K. pneumoniae 1226 (40.3%) was the most prevalent isolate among male patients while E. coli (1135; 41.8%) was the most prevalent isolate among female patients. Conclusion Our study showed that the prevalence of carbapenem non-susceptible Gram-negative bacteria is relatively high, which therefore makes them very challenging to treat. The results show an urgent need for improved antibiotic stewardship strategies, including better surveillance and more effective infection control measures to reduce this issue. Further research into the molecular epidemiology and risk factors associated with these infections is necessary to guide public health policymakers in developing interventions to help control the spread of carbapenem-resistant Gram-negative bacteria.
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OBJECTIVES: To investigate the acquired resistome in 18 colistin-resistant Escherichia coli isolated from different poultry farms in Lebanon, analyse Inc plasmids associated with mcr and assess potential transmission to humans. METHODS: A total of 18 E. coli were recovered from poultry faeces collected from different poultry farms in Lebanon. Broth microdilution (BMD) assay was performed to determine the antimicrobial resistance profiles. WGS was used to identify the genetic determinants behind the resistance in these isolates. RESULTS: BMD results showed that all of the 18 isolates were colistin resistant. Furthermore, resistance to trimethoprim/sulfamethoxazole was the most recorded among the isolates and only one isolate was resistant to cefepime. Sequencing results showed that the isolates were distributed into seven different STs and that the most abundant was ST1140. The number of antimicrobial resistant determinants ranged from 4 to 21 among the 18 isolates, with tet(A) and floR being the most frequent. Moreover, a total of 15 different plasmid replicon types were identified. The mcr-1 gene was shown to be predominantly located on IncX4 plasmids. Additionally, two isolates harboured the IncI2-type self-conjugative plasmid. CONCLUSIONS: The findings show that mcr and other important resistance determinants occur in MDR E. coli isolated poultry farms in Lebanon. The occurrence of mcr on mobile plasmids and the zoonotic potential and clinical relevance of some strains highlight a risk of transmission to humans.
