Disinfectant and antibiotic activities: a comparative analysis in Brazilian hospital bacterial isolates

Abstract

Nosocomial infections are an important cause of morbidity and mortality all over the world. It has been shown that appropriate environmental hygienic and disinfection practices can be very helpful to hospital infection control. The purpose of this study was to evaluate the bactericidal activity of some disinfectants against antibiotic-susceptible and antibiotic-resistant hospital bacterial isolates. The susceptibility of 27 clinical isolates to disinfectants and antibiotics was determined by the Association of Official Analytical Chemist's (AOAC) Use-Dilution method and by the Kirby-Bauer method, respectively. All strains tested were susceptible to sodium hypochlorite, glutaraldehyde and to the association quaternary ammoniumformaldehyde -ethyl alcohol disinfectants. However, the susceptibility of strains to phenol and to one quaternary ammonium compound was variable. Among twenty-one antibiotic-multiresistant strains (methicillin-resistant staphylococci, Enterococcus spp, Pseudomonas aeruginosa, Klebsiella pneumoniae, Proteus mirabilis, Enterobacter cloacae, Serratia marcescens and Escherichia coli) eleven (52%) and eight (38%) strains were resistant to the quaternary ammonium and phenol compounds, respectively. Among six isolates that demonstrated susceptibility to antibiotics (staphylococci, Enterococcus spp, P. mirabilis, E. cloacae and E. coli) two strains (33%) showed resistance to these disinfectants. The results demonstrated the lack of correlation between antibiotic-susceptibility and susceptibility to disinfectants in hospital strains.

Disinfection with sodium hypochlorite in hospital environmental surfaces in the reduction of contamination and infection prevention: a systematic review

“…The hypochlorite was superior to quaternary ammonium (13,19,22,25) , composed by quaternary ammonium (17) , detergent (13,24) , hydrogen peroxide (13) , povidone iodine (17) , 4% chlorhexidine (17) , phenolic (19) . It was equivalent to 2% quaternary ammonium (12) chlorhexidine (12) , formaldehyde (12) , ethanol (25) , NaOH (25) , peracetic acid (15) , hydrogen peroxide (16) , aldehydes (19) , and phenol in the presence of large amounts of organic matter (14) .…”

“…Most of them were correlated to inactivation rates, reduction or inhibition of microbial growth (13,(15)(16)(17)(18)(19)21,25) . Furthermore, a study tested the outcome microbial resistance (12) .…”

“…Furthermore, a study tested the outcome microbial resistance (12) . With two exceptions (14,25) , the other studies presented results favorable to the action of sodium hypochlorite to the proposed outcomes, either for inactivation or inhibition of microbial growth (13,(15)(16)(17)(18)(19)21) , reduction of infection (20,(22)(23)(24) , microbial resistance (12) . Among the exceptions, one of them showed loss of efficiency in a situation of heavy dirtying with organic matter (14) .…”

“…All studies used interventions and tested the action of sodium hypochlorite. Regarding the type of intervention, they are divided between those which conducted tests only in laboratory (in vitro) (12)(13)(14)(15)(16)(17)(18)(19) and those which tested samples directly (in situ) in various environmental surfaces: floors, walls, equipment etc. (20)(21)(22)(23)(24) .…”

“…Among the tested microorganisms, most strains represented clinical isolates from patients or surfaces and equipment, being resistant to several antibiotics. The most tested microorganism was C. difficile (13,16,(20)(21)(22)(23)(24) , followed by S. aureus, MRSA or not (12,(14)(15)19) , various species of Candida (17) and lipophilic viruses (25) , various Gram (18) , E. coli (14) and others (19) .…”