Nitrofurantoin

Antibiotic susceptibility was determined on Mueller–Hinton agar using the standard disk diffusion method, as described by the European Committee on Antimicrobial Susceptibility Testing (EUCAST) 2017 and also using the Phoenix system. Seventeen antibiotics (bioMérieux, Marcy L’Etoile, France) were tested, namely, amoxicillin (AMX), amoxicillin/clavulanate (AMC), piperacillin/tazobactam (PTZ), cephalothin (CEF), ceftriaxone (CRO), cefepime (CPM), ertapenem (ETP), imipenem (IMP), amikacin (AMK), gentamicin (GEN), ciprofloxacin (CIP), Fosfomycin (FOS), nitrofurantoin (NIT), doxycycline (DCI), trimethoprim/sulfamethoxazole (SXT) and colistin (CS). Sensitivity to imipenem, ertapenem, meropenem (MEM) and colistin was confirmed by the antimicrobial gradient method Etest (bioMérieux, Marcy L’Etoile, France) in collected isolates.

The antibiotic susceptibility profile of the isolates was identified using the standard disk diffusion method on Mueller–Hinton agar (bioMérieux, Marcy l’Etoile, France). Sixteen different antibiotics were tested, including amoxicillin (20 μg), amoxicillin-clavulanic acid (20/10 μg), piperacillin-tazobactam (30/6 μg), cephalotin (30 μg), ceftriaxone (30 μg), cefepime (30 μg), ertapenem (10 μg), imipenem (10 μg), amikacin (30 μg), gentamicin (10 μg), ciprofloxacin (5 μg), Fosfomycin (200 μg), nitrofurantoin (100 μg), tobramycin (10 μg), trimethoprim-sulfamethoxazole (1.25/23.75 μg), and colistin (10 μg) (bioMérieux, Marcy l’Etoile, France). The minimal inhibitory concentration (MIC) of colistin, ertapenem, and imipenem was identified using the microdilution and the E-test methods, respectively. Each strain was considered to be resistant to colistin, ertapenem, and imipenem if their MICs were greater than 2 mg/L, 1 mg/L, and 8 mg/L, respectively. The results were interpreted according to the European Microbial Medical Sensitivity Committee (EUCAST) 2017 (http://www.Sfmicrobiology.Org/Userfiles/Files/Files/CASFM/CASF%20V2_0_MAI2017.PDF, accessed on 25 September 2020).