ACTIVITY OF SEFT AZIDIME AGAINST ISOLATES
L*, Mustafa OZCAN*, TOlin AKSEBZECi*
In vitro activity of seftazidime was determined using an agar dilution technique
· clinical bacterial isolates. It was shown that seftazidime is highly active against bacteria including Pseudomonas sp. and exerts poor activity against some
Bacterial Isolates, in vitro activity, seftazidime
ars a number of broad spectrum antibiotics have been developed. Seftazidime cephalosporine with a wide range of aminoglycosides against Pseudomonas in vitro is a well documanted phenomenon that has recognised in vivo (1·4). This paper presents the in vitro antibacterial activities of seftazidime clinical isolates.
of seftazidime was compared with Cefoperazone, Monobactam and Tobramycin y isolated microorganisms from clinical source. Antibiotic powders were from their manufactures and standart solutions were prepared by weighing powder into a known volume of water. Agar plates (Diagnostic sensitivity test agar, made to contain concentration of antimicrobials as doubling dilutions in the to 128 mg/1. Overnight broth (Brain-heart infusion, Difco) cultures prepared from were diluted in saline that inocula of 1
o6
cfu in 0.1 mi. Eight different cultures d onto a 1oo
mm diameter plate and incubated for 12 h in a suitable before being read by eye. The minimal i!lhibitory concentration (MIC) was taken concentration showing no growth or a markedly reduced growth in colony or size, as compared to growth on an antibiotic free control plate.and Discussion
activity of seftazidime was determined using an agar dilution technique with inocula cfu against 596 clinical bacterial isolates and evaluated in comparison with
• monobactam and tobramycin. Susceptibility to antibiotics was determined by I activity and proved to be highly active against Gram negative bacteria Salmonella and Shigella sps, E.coli, Proteus sp, Citrobacter sp, Klebsiella sp, sp, and Enterobacter sp with M ICs being <1 to 8 mg/1, which are usually to cefoperazone and tobramycin (Table 1).
University Medical School, Dept. of Microbiology
In Vitro Activity of Seftazidime Against Clinical Isolates: OZBAL, Yusuf ve ark.
Table I. In vitro activity of seyftazidime, cefoperazone, monobactam and tobramycin gram-negative bacteria
Organisims
(no.of strains tested) Citrobacter sp
15
Enterobacter sp 81
Escherichia coli 76
Klebsiella sp 20
Proteus sp 72
Pseudomonas sp 91
Salmonella sp 45
Shigella sp 32
Erciyes T1p Dergisi/1311991
Antibiotics Seftazidime Cefoperazone Monobactam Tobramycin Seftazidime Cefoperazone Monobactam Tobramycin Seftazidime Cefoperazone Mono bact am Tobramycin Seftazidime Cefoperazone Monobactam Tobramycin Seftazidime Cefoperazone Monobactam Tobramycin Seftazidime Cefoperazone Monobactam Tobramycin Seftazidime Cefoperazone Monobactam Tobramycin Seftazidime Cefoperazone Monobactam Tobramycin
MIC mg/1 with an inoculum of 1 o6 cfu
MIC 90 1 8 1 16 8 64 4 32
<1 8
2 1 32
<1 16 1 32 1 8 4 128 16 128
<1 1
<1
<1
<1 1
<1 2
235
of Seftazidime Against Clinical Isolates: 6ZBAL, Yusuf ve ark.
e of activity was also demonstrated against the beta lactamase producing and strains of some Gram positive cocci (Table II). ' vitro activity of seftazidime, cefoperazone, monobactam, and tobramycin against
bacteria
epidermidis
Antibiotics
Seftadizime Cefoperazone Monobactam Tobramycin Seftadizime Cefoperazone Monobactam Tobramycin Seftazidime Cefoperazone Monobactam Tobramycin Seftazidime Cefoperazone Monobactam · Tobramycin Seftazidime Cefoperazone Monobactam Tobramycin
Minimal inhibitory concentration for 90 % of the strains.
MIC mg/1 with an Inoculum of 1 o6 cfu
MICgo
32 8 128
4 16 16
>128 16 8 1 64
4 4
<1 16
1
>128 8
>128 16
showed poor activity against Streptococcus faecalis and moderate activity ylococcus aureus. Its activity was markedly greater than cefoperazone and and was equal to or higher than that of monobactam against
eae .
. is a higly active, and a beta-lactamase-stable agent which may be clinically resistant bacterial infections and its anti-pseudomonal activity is encouraging.
236
In Vitro Activity of Seftazidime Against Clinical Isolates: OZBAL, Yusuf ve ark.
References
1. Neu HC: Beta-lactam antibiotics: Sructural relationships affecting in vitro activity and pharmacologic properties. Reviews of Infect Dis 8(Suppl 3): 237-259, 1986.
2. Ozbal Y, Fazli $ A , arslan N : In vitro activity of cefoperazone against clinical isolates.
Proceedings lnt Cong Dis. Cairo 1985, pp 40-43.
3. Reeves D S, Holt H A, Bywater m J: Comperative activity in vitro of Ceftazidime and nine other antibacterial agents. Infection 11 (Suppl): 3-11, 1983.
4. Schassan H H, Fedder J: Activity of cettazidime and newer antibiotics against Gram-negative bacilli. J Antimicrob Chemother 8(Suppl B) : 79-82, 1981.
Erciyes T1p Dergisi/1311991 237
