Antibiotic Resistance In Clinical Isolates Of Pseudomonas Aeruginosa In Enugu And Abakaliki, Nigeria
E Amadi, P Uzoaru, I Orji, A Nwaziri, I Iroha
antibiotic, inhibition, pus, resistance, wound
E Amadi, P Uzoaru, I Orji, A Nwaziri, I Iroha. Antibiotic Resistance In Clinical Isolates Of Pseudomonas Aeruginosa In Enugu And Abakaliki, Nigeria. The Internet Journal of Infectious Diseases. 2008 Volume 7 Number 1.
The resistance of
The greatest challenge facing the effective management of
Materials And Methods
Isolation of Test Organism
A total of fifty pus samples were collected from wound infection patients at the National Orthopedic Hospital Enugu (NOHE) and Ebonyi State University Teaching Hospital (EBSUTH) Abakaliki between July and September 2006. Sixteen samples were obtained from NOHE while thirty four were collected from EBSUTH using sterile swab sticks. The samples were inoculated into nutrient agar media and incubated at 37 ° C for 24 hours. Subsequently the colonies were sub-cultured using the streak plate technique ( 12 ).
The isolates were identified using colony morphology, motility testing, Grams reaction and Biochemical tests as described by Cheesbrough ( 1 ) and Amadi and Ayogu, ( 13).
Preparation of antibiotic discs
The antibiotic disc used for the study were prepared according to the method described by Isu and Onyeagba ( 12).The antibiotics used were Chloramphenicol, Ciprofloxacin, Amoxycillin, Streptomycin, Gentamicin and Co-trimoxazole obtained from a pharmaceutical company in Abakaliki. All the antibiotics had the official registration number of the National Agency for Food and Drug administration and Control (NAFDAC) Nigeria, with their expiration dates ranging from June 2008 to July 2010. The discs were impregnated with the antibiotics to obtain the following concentrations per disc, Ciprofloxacin (10µg), Streptomycin (30µg), Amoxycillin (30µg), Gentamicin (10µg), Chloramphenicol (30µg) and Co-trimoxazole (30µg).
Antibiotic Sensitivity Screening
Overnight old cultures of the respective isolates, adjusted to McFarland 0.5 ( 1) were used for the sensitivity testing. The Kirby-Bauer modified disc diffusion technique ( 1 ) was used to determine the sensitivity of the antibiotics. The discs were evenly distributed on the sensitivity agar in such a way that they were 15mm from the edge of the plate and 25mm from one disc to another. Each disc was slightly pressed down to ensure its sufficient contact with the agar media. The plates were then incubated at 37 ° C for 24 hours. The inhibition zone diameter (IZD) were subsequently measured using meter rule. The diameter of the disc (6mm) were subtracted from the total inhibition zone diameter of each antibiotic disc to obtain the final IZD. Resistance were regarded as IZD between 0 –5mm while sensitivity was considered IZD above 5mm ( 14).
Isolation and Identification of isolates
Out of the fifty pus samples obtained from patients in Enugu and Abakaliki, 34 (68%) yielded
Sensitivity pattern of antibiotics on isolates
The isolates had their highest resistance against amoxycillin (88.2%) and the least against Ciprofloxacin (23.5%) (Table 2,3). Seven isolates (20.6%) were 100% resistant to all the antibiotics screened in this study (Tabe 3). It was also observed that 79% of the isolates were multi-drug resistant.
Ciprofloxacin has been stated to be the most potent drug available for the treatment of
Gentamicin, like ciprofloxacin is one of the drugs generally considered to be effective in the treatment of infections caused by resistant strains of
The 67.6% resistance of
Furthermore, the high rate of resistance to chloramphenicol (58.8%), amoxycillin (88.2%) and co-trimoxazole (76.5%) as recorded in this study appears to corroborate a previous suggestion ( 17 ) that these three drugs should no longer be considered effective for the treatment of
Seventy nine percent of
The relatively high resistance of
Department of Applied Microbiology
Faculty of Applied and Natural Sciences
Ebonyi State University, PMB 053 Abakaliki,
Ebonyi State, Nigeria.