Table 3. Antimicrobial-susceptibility patterns of Gram-negative isolates to different antibiotics.

Antibiotic	Acinetobacter baumannii (n=11)	Klebsiella pneumoniae (n=10)	Pseudomonas aeruginosa (n=9)	Achromobacter denitrificans (n=7)	Escherichia coli (n=1)	Enterobacter aerogenes (n=1)
	n (%)	n (%)	n (%)	n (%)	n (%)	n (%)
Ampicillin	-	10 (100) ‡	-	-	1 (100.0) ‡	1 (100.0) ‡
Amoxicillin/ clavulanic acid	-	6 (60.0) *	-	-	1 (100.0) ***	1 (100.0) ‡
Amoxicillin	-	10 (100) ‡	-	-	-	1 (100.0) ‡
Amikacin	7 (63.6) *	9 (90.0) ***	9 (100.0) ***	7 (100.0) ‡	1 (100.0) ***	1 (100.0) ***
Ceftazidime	11 (100.0) ‡	6 (60.0) *	9 (100.0) ***	5/6 (83.3) **	1 (100.0) ‡	1 (100.0) ‡
Ceftriaxone	11 (100.0) ‡	2 (20.0) *	-	7 (100.0) ‡	1 (100.0) ‡	1 (100.0) ‡
Cefotaxime	11 (100.0) ‡	2 (20.0) *	9 (100.0) ‡	7 (100.0) ‡	1 (100.0) ‡	1 (100.0) ‡
Doxycycline	3 (27.3) *	7 (70.0) **	-	4 (57.1) *	1 (100.0) ***	1 (100.0) ***
Doripenem	1 (9.1) *	8 (80.0) **	8 (88.9) **	-	1 (100.0) ***	1 (100.0) ***
Cefoxitin	-	8 (80.0) **	-	-	1 (100.0) ***	1 (100.0) ‡
Gentamycin	1 (9.1) *	5 (50.0) *	9 (100.0) ***	2 (28.6) *	1 (100.0) ***	1 (100.0) ***
Imipenem	1 (9.1) *	8 (80.0) **	9 (100.0) ***	7 (100.0) ***	1 (100.0) ***	1 (100.0) ***
Levofloxacin	1 (9.1) *	6 (60.0) *	8 (88.9) **	7 (100.0) ‡	1 (100.0) ‡	1 (100.0) ***
Meropenem	1 (9.1) *	8 (80.0) **	9 (100.0) ***	3/6 (50.0) *	1 (100.0) ***	1 (100.0) ***
Polymyxin B	10 (90.9) ***	-	9 (100.0) ***	-	-	-
Cefoperazone/ sulbactam	3 (27.3) *	8 (80.0) **	9 (100.0) ***	7 (100.0) ‡	1 (100.0) ***	1 (100.0) ***
Tobramycin	4 (36.4) *	7 (70.0) **	9 (100.0) ***	5 (71.4) **	1 (100.0) ‡	1 (100.0) ***
Piperacillin/tazobactam	11 (100.0) ‡	7 (70.0) **	7/8 (87.5) **	7 (100.0) ***	1 (100.0) ***	1 (100.0) ***

‡ Resistant

*<70% of isolates are susceptible

** 70–90% of isolates are susceptible

*** ≥ 90% of isolates are susceptible

-Intrinsic resistance