TABLE 3.

Frequency of aminoglycoside-modifying enzyme genotypes, their predicted substrate specificity, number susceptible by the broth microdilution method, and correlation of PFGE types of 107 clinical isolates of Acinetobacter baumannii-calcoaceticus complex

GenotypeNo. (%) of isolatesSubtrate(s)aNo. of isolates susceptible toa:PFGEb type(s) (no. of isolates)
GENTOBAMK
aph(3′)-Ia + ant(2")-Ia38 (35.5)GEN, TOB0121 (31), 8 (1), 10 (1), 11 (3), 18 (1), 21 (1)
ant(2")-Ia23 (21.5)GEN, TOB0012 (15), 3 (5), 17 (1), 23 (1), 25 (1)
aac(6′)-Ih + aph(3′)-Ia11 (10.3)TOB, AMK0994 (4), 6 (1), 7 (1), 13 (4), 22 (1)
aac(3)-Ia9 (8.4)GEN3735 (6), 16 (1), 24 (1), 29 (1)
aac(6′)-Ih6 (5.6)TOB, AMK0505 (6)
aac(3)-IIa4 (3.7)GEN, TOB00014 (3), 20 (1)
aac(3)-Ia + aph(3′)-Ia4 (3.7)GEN0221 (1), 4 (2), 6 (1)
aac(3)-Ia + ant(2")-Ia2 (1.9)GEN, TOB0009 (2)
aac(3)-Ia + aph(3′)-Ia + aph(3′)-VI2 (1.9)GEN0107 (2)
aac(3)-Ia + aph(3′)-VI1 (0.9)GEN, AMK0104 (1)
aac(6′)-Ib + ant(2")-Ia1 (0.9)GEN, TOB, AMK00012 (1)
aac(6′)-Ih + aph(3′)-VI1 (0.9)TOB, AMK01015 (1)
aph(3′)-Ia + aph(3′)-VI1 (0.9)1101 (1)
aph(3′)-VI + ant(2")-Ia1 (0.9)GEN, TOB, AMK0002 (1)
aac(3)-Ia + aph(3′)-Ia + ant(2")-Ia1 (0.9)GEN, TOB0001 (1)
aac(6′)-Ih + aph(3′)-Ia + ant(2")-Ia1 (0.9)GEN, TOB0001 (1)
None present1 (0.9)11119 (1)
  • a GEN, gentamicin; TOB, tobramycin; AMK, amikacin.

  • b PFGE, pulsed-field gel electrophoresis.