TABLE 2.

Susceptibility of P. aeruginosa isolates to antimicrobial agents according to patient age (data from 1999 to 2002 combined)

Antimicrobial agent(s)	Patient age (yr)	Total no. of isolates	% Sa	% Ia	% Ra
Amikacin	18-39	8,479	76.7	7.2	16.2
	40-49	5,113	90.7	3.9	5.4
	50-59	6,512	91.5	3.8	4.8
	60-69	7,086	92.4	3.8	3.8
	≥70	15,778	93.7	3.3	3.0
Cefepime	18-39	8,479	72.8	14.1	13.1
	40-49	5,113	76.1	14.0	9.8
	50-59	6,512	74.6	14.4	11.0
	60-69	7,086	74.8	15.1	10.0
	≥70	15,778	79.4	12.7	7.9
Ceftazidime	18-39	8,479	77.9	7.2	14.8
	40-49	5,113	77.5	8.4	14.1
	50-59	6,512	74.8	9.3	15.9
	60-69	7,086	75.4	10.0	14.6
	≥70	15,778	78.0	10.5	11.5
Ciprofloxacin	18-39	8,479	55.8	10.5	33.7
	40-49	5,113	59.7	7.3	33.0
	50-59	6,512	58.3	7.6	34.1
	60-69	7,086	61.7	5.6	32.7
	≥70	15,778	61.4	5.9	32.7
Gentamicin	18-39	8,479	61.2	11.1	27.7
	40-49	5,113	72.9	9.6	17.5
	50-59	6,512	73.1	8.1	18.8
	60-69	7,086	75.2	8.8	16.0
	≥70	15,778	75.2	10.1	14.6
Imipenem	18-39	8,479	77.9	6.0	16.1
	40-49	5,113	76.7	5.4	17.9
	50-59	6,512	76.5	7.0	16.5
	60-69	7,086	76.0	7.2	16.8
	≥70	15,778	81.1	6.9	11.9
Piperacillin	18-39	8,479	82.7	-b	17.3
	40-49	5,113	83.0	-	17.0
	50-59	6,512	80.7	-	19.3
	60-69	7,086	82.2	-	17.8
	≥70	15,778	85.6	-	14.4
Piperacillin-tazobactam	18-39	8,479	87.6	-	12.4
	40-49	5,113	88.1	-	11.9
	50-59	6,512	86.5	-	13.5
	60-69	7,086	87.0	-	13.0
	≥70	15,778	90.4	-	9.6
Ticarcillin-clavulanate	18-39	8,479	71.3	-	28.7
	40-49	5,113	68.2	-	31.8
	50-59	6,512	64.7	-	35.3
	60-69	7,086	65.7	-	34.3
	≥70	15,778	69.9	-	30.1
Tobramycin	18-39	8,479	80.0	4.0	16.0
	40-49	5,113	85.9	1.6	12.5
	50-59	6,512	84.3	1.6	14.1
	60-69	7,086	86.9	1.5	11.7
	≥70	15,778	87.6	1.6	10.7

^aThe percentages of susceptible (S), intermediate (I), and resistant (R) isolates according to NCCLS breakpoints are shown.

^b-, NCCLS breakpoints for the intermediate category unavailable.