Piperacillin tazobactam

Antimicrobial susceptibility pattern of the 32 CRISPR/Cas-positive P. aeruginosa isolates and 32 randomly selected CRISPR/Cas-negative isolates from the same sources was conducted using the Kirby-Bauer disc diffusion technique (Bauer 1966 (link)). Susceptibility to various groups of antimicrobial agents was examined; therefore, antibiotic discs (Bioanalyse®, Turkey): piperacillin (100 μg), piperacillin-tazobactam (100/10 μg), ceftazidime (30 μg), cefepime (30 μg), amikacin (30 μg), imipenem (10 μg), meropenem (10 μg), ciprofloxacin (5 μg), and levofloxacin (5 μg) were used. Zone of inhibition diameter was determined and elucidated in accordance with Clinical and Laboratory Standards Institute guidelines (CLSI 2021 ).

Altogether n = 155 identified uropathogenic E. coli (UPEC) were collected during the period of August 2012 to August 2014, from Pakistan Institute of Medical Sciences. Ethical Review Board (ERB) of Pakistan Institute of Medical Sciences approved this study. Ethical Review Board approved verbal consent taken from all the patients. Important patient data such as name, age, gender, location was recorded and unique identification number were assigned to each patient. Samples were from community-acquired urinary tract infections. Antibiotic testing and phenotypic detections of ESBL were performed by disc diffusion methods according to the guidelines CLSI, 2014 [13 ]. Isolates were tested for the susceptibility to 12 different classes of antibiotics including β-lactamase inhibitors (piperacillin tazobactam, amoxicillin-clavulanic acid), cephalosporins (ceftazidime, cefotaxime, ceftriaxone), fluoroquinolone (ciprofloxacin, levofloxacin), aminoglycosides (amikacin), trimethoprim sulfonamides, nitrofurantoin, and fosfomycin (BIOANALYSE, Turkey). Control strain E. coli ATCC 25922 was used in this assay.

The susceptibility of E. marmotae M-12 to antibiotics was determined by the standard disc-diffusion method. Testing was performed following EUCAST 2022 guidance on the Mueller–Hinton agar (Himedia). The following discs with antibiotics were used (20 antibiotics in total): amoxicillin-clavulanic acid (20–10 µg), gentamicin (10 µg), trimetoprim-sulfametoxazol (1.25–23.75 µg) (NICF, Russia); aztreonam (30 µg), piperacillin (30 µg), piperacillin-tazobactam (100–10 µg), amikacin (30 µg), tobramycin (10 µg), ticarcillin-clavulanic acid (75–10 µg), ticarcillin (75 µg) (Bioanalyse, Turkey); ampicillin (10 µg), meropenem (10 µg), imipenem (10 µg), cefotaxime (5 µg), cefepime (30 µg), ceftazidime (10 µg), ciprofloxacin (5 µg), levofloxacin (5 µg), chloramphenicol (30 µg), trimethoprim (5 µg) (HiMedia, India).