TABLE 2.

Comparison of 24-h CFU reductions following TMP/SMZ exposure in time-kill studies between S. maltophilia and E. coli at the same MIC in CAMHB and by broth for individual isolates^a

Comparison	Mean change in log10 CFU/mL at 24 h ± SD		P valueb
By isolate at the same MIC (TMP/SMZ MIC [μg/mL])	S. maltophilia	E. coli
CAMHB
STM29 vs EC25922 (0.25/4.75)	0.60 ± 0.08	−4.49 ± 0.06	<0.001
STMC43-11 vs EC762 (1/19)	0.81 ± 0.16	−1.73 ± 0.10	0.007
STM106 vs EC778 (2/38)	1.07 ± 0.16	−1.59 ± 0.26	0.005
STMC42-15 vs EC780 (4/76)	1.36 ± 0.08	1.83 ± 0.07	0.016
ISO brothc
STM29 vs EC25922 (0.25/4.75)	0.49 ± 0.06	−4.42 ± 0.65	<0.001
STMC43-11 vs EC762 (1/19)	1.15 ± 0.06	−2.93 ± 0.16	0.002
STM106 vs EC778 (2/38)	1.03 ± 0.18	−1.46 ± 0.24	0.003
STMC42-15 vs EC780 (4/76)	1.52 ± 0.15	1.20 ± 0.11	NS
By broth for individual isolates	CAMHB	ISO broth
S. maltophilia
STM29	0.60 ± 0.08	0.49 ± 0.06	NS
STMC43-11	0.81 ± 0.16	1.15 ± 0.06	NS
STM106	1.07 ± 0.16	1.03 ± 0.18	NS
STMC42-15	1.36 ± 0.08	1.52 ± 0.15	NS
E. coli
EC25922	−4.49 ± 0.06	−4.42 ± 0.65	NS
EC762	−1.73 ± 0.10	−2.93 ± 0.16	0.010
EC778	−1.59 ± 0.26	−1.46 ± 0.24	NS
EC780	1.83 ± 0.07	1.20 ± 0.11	0.022

^aTMP/SMZ, trimethoprim/sulfamethoxazole; CAMHB, cation-adjusted Mueller-Hinton broth; ISO broth, ISO-Sensitest broth; NS, not significant.

^bComparisons were done by one-way ANOVA and the Holm-Sidak pairwise test for multiple comparisons.

^cIsolates referenced by their CAMHB MICs during comparison.