In vitro activity of ceftazidime-avibactam against gram-negative bacteria in patients with bacteremia and skin and soft-tissue infections in Colombia 2019-2021.

OBJECTIVES: Ceftazidime-avibactam (CAZ-AVI) is an option for infections caused by MDR gram-negative bacilli. In this study, we aimed to analyze the in vitro antimicrobial activity of CAZ-AVI and other antimicrobial agents against gram-negative bacilli that were collected in Colombia between 2019 and 2021 from patients with bacteremia and skin and soft-tissue infections (SSTIs). METHODS: A total of 600 Enterobacterales and 259 P. aeruginosa strains were analyzed. The phenotypic resistance of isolates, particularly non-susceptibility to meropenem, multidrug-resistant (MDR) isolates, and difficult-to-treat (DTR) P. aeruginosa, was evaluated according to CLSI breakpoints. RESULTS: Enterobacterales had the most susceptibility to CAZ-AVI (96.5 %) and tigecycline (95 %). Tigecycline and CAZ-AVI were the antimicrobial agents with the most in vitro activity against carbapenem-resistant Enterobacterales (CRE). CAZ-AVI was the antimicrobial treatment with the most activity against P. aeruginosa. CONCLUSIONS: Tigecycline and CAZ-AVI were the antimicrobial agents with the most activity against CRE and MDR Enterobacterales. For P. aeruginosa, CAZ-AVI was the antimicrobial treatment with the most in vitro activity.

In vitro activity of ceftazidime-avibactam against Gram-negative strains in patients with complicated urinary tract infection and complicated intra-abdominal infection in Colombia 2014-2018.

Ceftazidime/avibactam (CAZ/AVI) has excellent in vitro activity against enterobacterales and Pseudomonas aeruginosa. The study aimed to analyze the in vitro antimicrobial activity of CAZ/AVI and other antibiotics against isolates of enterobacterales and P. aeruginosa from patients with complicated urinary tract infection (cUTI) and complicated intra-abdominal infection (cIAI) in Colombian hospitals between 2014 and 2018, using the Antimicrobial Testing Leadership and Surveillance (ATLAS) database. Enterobacterales and P. aeruginosa samples were obtained from patients with cUTI and cIAI. Susceptibility was determined using The Clinical and Laboratory Standards Institute (CLSI) breakpoints. Meropenem-non-susceptible isolates were screened for extended-spectrum ß-lactamase (ESBL) production. Isolates that were positive for ESBL activity were examined by Multiplex Polymerase Chain Reaction (Multiplex PCR) to detect genotypic resistance. A total of 565 Enterobacterales and 95 P. aeruginosa from patients with cUTI and 345 Enterobacterales and 65 P. aeruginosa from patients with cIAI were isolated. In vitro activity showed susceptibility to CAZ/AVI greater than 99% for Enterobacterales and in lower percentages for P. aeruginosa in cUTI (78.46%) and cIAI (83.33%). CAZ/AVI showed good in vitro activity against multidrug-resistant (MDR) Enterobacterales and P. aeruginosa in patients with cUTI and cIAI.

In vitro activity of ceftazidime/avibactam against Gram-negative strains in Colombia 2014-2018.

OBJECTIVES: Ceftazidime/avibactam (CAZ/AVI) has shown in vitro activity against multidrug-resistant (MDR) Gram-negative bacteria, especially Enterobacterales and carbapenem-resistant Pseudomonas aeruginosa. However, in vitro activity of CAZ/AVI against Gram-negative bacteria in Colombian hospitals is still unknown. The study aimed to analyse the in vitro antimicrobial activity of CAZ/AVI against Gram-negative bacteria collected from hospitals in Colombia using the Antimicrobial Testing Leadership and Surveillance (ATLAS) database. METHODS: Enterobacterales and P. aeruginosa samples were obtained from four hospitals in Colombia between 2014 and 2018. Samples of blood, abdominal fluid, urine, soft tissues, and respiratory tract were collected from adult and paediatric patients. The 2020 Clinical and Laboratory Standards Institute (CLSI) breakpoints were used for the interpretation of susceptibility. Meropenem-non-susceptible Enterobacterales and P. aeruginosa isolates were screened for extended-spectrum ß-lactamase (ESBL) production. Isolates that were positive for ESBL activity were examined by PCR for detecting genotypic resistance. RESULTS: A total of 2005 Enterobacterales were isolated; 29.28% were not susceptible to levofloxacin, 29.14% to aztreonam, and 25.19% to cefepime. The CAZ/AVI was the antibiotic with the best susceptibility against carbapenem-resistant Enterobacterales (CRE) (94.64%), non-metallo-ß-lactamase(MBL)-producing Enterobacterales (98.06%), and MDR Enterobacterales (98.36%). For carbapenem-resistant P. aeruginosa, in vitro activity of CAZ/AVI was 59.26%, and 50% for non-MBL-producing P. aeruginosa. CONCLUSION: CAZ/AVI shows excellent in vitro activity against MDR Enterobacterales and CRE. For MDR P. aeruginosa and carbapenem-resistant P. aeruginosa, in vitro activity of CAZ/AVI was lower compared to the activity against Enterobacterales, but CAZ/AVI was the antibiotic with the best activity.

In vitro activity of ceftazidime-avibactam against Gram-negative strains in patients with complicated urinary tract infection and complicated intra-abdominal infection in Colombia 2014-2018

ABSTRACT Ceftazidime/avibactam (CAZ/AVI) has excellent in vitro activity against enterobacterales and Pseudomonas aeruginosa. The study aimed to analyze the in vitro antimicrobial activity of CAZ/AVI and other antibiotics against isolates of enterobacterales and P. aeruginosa from patients with complicated urinary tract infection (cUTI) and complicated intra-abdominal infection (cIAI) in Colombian hospitals between 2014 and 2018, using the Antimicrobial Testing Leadership and Surveillance (ATLAS) database. Enterobacterales and P. aeruginosa samples were obtained from patients with cUTI and cIAI. Susceptibility was determined using The Clinical and Laboratory Standards Institute (CLSI) breakpoints. Meropenem-non-susceptible isolates were screened for extended-spectrum b-lactamase (ESBL) production. Isolates that were positive for ESBL activity were examined by Multiplex Polymerase Chain Reaction (Multiplex PCR) to detect genotypic resistance. A total of 565 Enterobacterales and 95 P. aeruginosa from patients with cUTI and 345 Enterobacterales and 65 P. aeruginosa from patients with cIAI were isolated. In vitro activity showed susceptibility to CAZ/AVI greater than 99% for Enterobacterales and in lower percentages for P. aeruginosa in cUTI (78.46%) and cIAI (83.33%). CAZ/AVI showed good in vitro activity against multidrug-resistant (MDR) Enterobacterales and P. aeruginosa in patients with cUTI and cIAI.