TABLE 1.

MICs of 13 antimicrobial agents against 142 isolates of Acinetobacter baumannii-calcoaceticus complex from deployed and nondeployed U.S. military patientsa

DrugbResult for:
Deployed personnel (n = 95)Nondeployed personnel (n = 47)
MIC (μg/ml)c% SusceptibledMIC (μg/ml)c% Susceptibled
Range50%90%Range50%90%
Ampicillin-sulbactam
    No-growth end point2->1283212816*2->1281612847*
    Trailing end point2-128166438*≤1->12883260*
Sulbactam
    No-growth end point≤2->641664e≤2->64864
    Trailing end point≤2-32832≤2-32432
Imipenem
    No-growth end point≤0.5->162>1663*≤0.5->161>1687*
    Trailing end point≤0.5->161>1666*≤0.5->16≤0.5>1687*
Ticarcillin-clavulanate
    No-growth end point8->256>256>2565*4->25664>25626*
    Trailing end point≤2->256>256>2568*≤2->25632>25634*
Ceftazidime
    No-growth end point8->6464>649*4->64>646434*
    Trailing end point2->6432>64332->6432>6445
Colistin0.25-811990.5-81296
Polymyxin B0.5-412990.5-41298
Amikacin≤0.5->6416>64501->648>6451
Gentamicin≤0.5->8>8>87*≤0.5->8>8>838*
Azithromycin<1->8>8>82->8>8>8
Doxycycline≤0.25->168>1640≤0.25->164>1662
Minocycline≤0.12-161497≤0.12-80.5498
Tigecycline0.12->8280.12->812
  • a Deployed personnel are those who received care after suffering an injury while deployed in support of OIF or OEF (the current war in Afghanistan). Nondeployed personnel are those inpatients receiving care without a history of deployment in support of OIF/OEF.

  • b No-growth end point, MIC defined as the concentration that inhibited all visible bacterial growth; trailing end point, MIC defined as the concentration at which growth was reduced ≥80%. With a trailing end point, colonies or subtle growth patterns occurred above the determined MIC.

  • c 50 and 90%, MICs at which 50 and 90% of isolates are inhibited, respectively.

  • d According to CLSI criteria, except where otherwise indicated. *, P ≤ 0.01 for difference between isolates from deployed and nondeployed personnel.

  • e —, no interpretive criteria available.