TABLE 3

Antibiotic susceptibilities of E. aerogenes strains, combination CAZ-AVI, and effect of PMBN

StrainMIC (mg/liter)a
CHLPAβNNORNALCIPPIPAVIPMBNCAZCAZ + AVI 1CAZ + AVI 2CAZ + AVI 4CAZ + PMBNAVI + PMBNCAZ + PMBN + AVI 1CAZ + PMBN + AVI 2CAZ + PMBN + AVI 4CPTIPMMEMATMERT
ATCC 1503841,0240.12540.125282560.060.060.060.060.0680.060.06ND0.1250.1250.020.030.01
EA25121,02464>1,0243216425625621ND3240.50.125ND80.250.01640.25
EA35121,02464>1,02432128641,0241,0241682641620.50.25320.50.031280.5
EA52561,02464>1,02416128641,0241,024641681281610.50.1253240.51288
EA275121,02464>1,024161282565121,024646443280.50.030.036416112864
EA1175121,024128>1,024321281281,0241,02416162128810.50.1256420.125>1282
EADFJ 851,0241,02464>1,0243264161,024512882641611ND1610.02>1280.25
EADFJ 461,0241,024256>1,0242561281281,0241,02432881286411ND6481>12816
  • a CHL, chloramphenicol; PAβN, phenylalanine-arginine β-naphthylamide; NOR, norfloxacin; NAL, nalidixic acid; CIP, ciprofloxacin; PIP, piperacillin; AVI, avibactam (1, 2, or 4 mg/liter); PMBN, polymyxin B nonapeptide (used at MIC/10 for combination); CAZ, ceftazidime; CPT, ceftaroline; IPM, imipenem; MEM, meropenem; ATM, aztreonam; ERT, ertapenem; ND, not determined because of intrinsic susceptibility preventing the reading of a reliable endpoint.