Antimicrobial susceptibility test

The Kirby-Bauer disk-diffusion test was used to conduct drug sensitivity tests on Haemophilus test medium (HTM) plates and incubated for 24 h at 37°C with 5% CO₂ in air, according to the Clinical and Laboratory Standards Institute (CLSI) (15). Commonly used antibacterial drugs in H.influenzae infected patients in the area were taken into consideration. Fourteen antibiotics were tested: ceftazidime, ampicillin, amoxicillin-clavulanic acid, meropenem, levofloxacin, imipenem, tetracycline, chloramphenicol, ampicillin-sulbactam, aztreonam, cefepime, rifampin, cefaclor, azithromycin. H.influenzae ATCC 49247 was used for quality control.