In vitro susceptibility of gram-negative bacterial isolates to chlorhexidine gluconate.
OBJECTIVE
To investigate the susceptibility of clinical isolates of gram-negative bacteria to chlorhexidine gluconate.


METHODS
Prospective laboratory study.


METHODS
Tikur Anbessa Hospital, Addis Ababa, Ethiopia.


METHODS
Clinical specimens from 443 hospital patients.


METHODS
Significant number of gram negative bacteria were not inhibited by chlorhexidine gluconate (0.02-0.05%) used for antisepsis.


RESULTS
Four hundred and forty three strains of gram-negative bacteria were isolated from Tikur Anbessa Hospital patients. Escherichia coli (31.6%) and Klebsiella pneumoniae (23%) were the most frequently isolated bacteria followed by Proteus species (13.3%), Pseudomonas species (9.2%), and Citrobacter species (6.1%). Each organism was tested to chlorhexidine gluconate (CHG), minimum inhibitory concentration (MIC) ranging from 0.0001% to 1%w/v. All Salmonella species and E. coli were inhibited by CHG, MIC < or = 0.01%. Twenty nine per cent of Acinetobacter, 28% of K. pneumoniae and Enterobacter species and 19-25% of Pseudomonas, Proteus and Providencia species were only inhibited at high concentrations of CHG (> or = 0.1%).


CONCLUSIONS
Our results showed that a significant number of the gram-negative bacterial isolates were not inhibited by CHG at the concentration used for disinfection of wounds or instruments (MIC 0.02-0.05% w/v). It is therefore important to select appropriate concentration of this disinfectant and rationally use it for disinfection and hospital hygiene. Continuing follow up and surveillance is also needed to detect resistant bacteria to chlorhexidine or other disinfectants in time.
Mengistu
Y
Y
Department of Microbiology and Parasitology, Faculty of Medicine, Addis Ababa University, Ethiopia.
Erge
W
W
Bellete
B
B
D000900:Anti-Bacterial Agents; D002710:Chlorhexidine / Q000031:analogs & derivatives*; D003428:Cross Infection / Q000382:microbiology* / Q000517:prevention & control*; D004203:Disinfection / Q000379:methods*; D004352:Drug Resistance, Microbial; D005002:Ethiopia; D006090:Gram-Negative Bacteria / Q000145:classification / Q000187:drug effects* / Q000302:isolation & purification*; D016905:Gram-Negative Bacterial Infections / Q000382:microbiology* / Q000517:prevention & control*; D006786:Hospitals, Urban; D006801:Humans; D017053:Infection Control / Q000379:methods*; D008826:Microbial Sensitivity Tests; D011446:Prospective Studies; D012703:Serotyping
D000900:Anti-Bacterial Agents; C010882:chlorhexidine gluconate; D002710:Chlorhexidine