Journal of Drug Metabolism & Toxicology
Open Access

Cross resistance between commonly used biocides and antibiotics in hospitals

2^nd World Congress and Exhibition on Antibiotics and Antibiotic Resistance

October 13-15, 2016 Manchester, UK

Sylvia Adel Daniel Rofael, Hoda M G Omar, Hamida M Abou-Shleib, Michael Shawky and Moustafa A El-Nakeeb

University College London, UK
University of Alexandria, Egypt
University College Hospital, UK

Posters & Accepted Abstracts: J Drug Metab Toxicol

Abstract :

A concern about emergence of new antibiotic resistant strains in health care environment due to extensive exposure of hospital bacteria to sub-inhibitory concentrations of biocides has been expressed. Our aim was to reveal any possible link between adaptation to biocides and resistance to antibiotics in hospitals. A total of 66 clinical and environmental bacterial isolates; isolated from the Main University Hospital in Alexandria were screened for their susceptibility to 22 commonly used broad spectrum antibiotics and six biocides; Benzalkonium Chloride (BK), Cetrimide (CET); Chlorhexidine (CHX); povidone-iodine; sodium hypochlorite and dettol�?®. Then selected hospital isolates in addition to standard strains were adapted to the biocides by passing them in gradually increasing biocide concentrations. The maximum obtained Minimum Inhibitory Concentrations (MICs) were >3200 mg/L for BK and CET; >1000 mg/L for CHX. Cross resistance to antibiotics was then tested in the biocide adapted isolates using Stokeâ�?�?s method. Screening results revealed a moderate positive correlation between antibiotic resistance and biocide tolerance where Spearman correlation coefficient ranged between 0.376-0.278 (p<0.05). The stable adaptation to BK, CET and CHX resulted in reduced susceptibility towards certain antibiotics; amikacin, gentamicin, imipenem, ciprofloxacin, levofloxacin, chloramphenicol, ceftazidime, doxycycline, tetracycline, cefoperazone, cefotaxime and cefepime. In many cases, the observed cross resistance moved the strains from being â�?�?sensitiveâ�? to being â�?�?intermediately sensitiveâ�? or even â�?�?resistantâ�? to antibiotics. Therefore, biocides should be handled with care in health care settings avoiding sub-lethal concentrations. Cross resistance between biocides and antibiotics can aggravate the existing problem of antibiotic resistance in the healthcare system.

Biography :

Email: sylvia.daniel@alexu.edu.eg