Table 3.

In vitro activities of various antimicrobial agents against epidemic and sporadicA. baumannii isolates

A. baumannii group (no. of strains tested)AntibioticMIC (mg/liter)a% Susceptible
Range50%90%Geometric mean
Outbreak isolates (16)Gentamicin1–>8>8>812.125
Amikacin2–>328>3227.663
Amoxicillin-clavulanate4/2–>32/2 32/2>32/237.525
Mezlocillin8–>32>32>3245.531
Piperacillin-tazobactam≤1/4–32/44/4 16/47.094
Meropenem≤0.25–4120.96100
Imipenem≤0.25–1≤0.250.50.25100
Cefuroxime16–>3232>3241.00
Cefepime2–6481611.881
Ceftriaxone4–>3216>3233.544
Cefotaxime4–>1616>1618.744
Ciprofloxacin0.5–>88>810.613
Sporadic isolates (18)Gentamicin0.5–>81>85.067
Amikacin1–16483.6100
Amoxicillin-clavulanate≤0.25/2–>32/2 4/2>32/212.861
Mezlocillin8–>3216>3223.661
Piperacillin-tazobactam≤1/4–32/4≤1/4 16/45.3100
Meropenem≤0.25–10.510.51100
Imipenem≤0.25–0.5≤0.25≤0.250.14100
Cefuroxime16–>3232>3236.40
Cefepime1–8283.3100
Ceftriaxone4–>3281611.863
Cefotaxime4–>168>1611.863
Ciprofloxacin0.5–40.541.3100
  • a 50% and 90%, MICs at which 50 and 90% of the isolates are inhibited. Values separated with a shill apply to the first- and second-listed antibiotics of the compound, respectively.