engleski

In vitro antimicrobial efficacy of diluted sodium hypochlorite against Staphylococcus pseudintermedius, Pseudomonas aeruginosa and Malassezia pachydermatis

In vitro antimicrobial efficacy of diluted sodium hypochlorite against Staphylococcus pseudintermedius, Pseudomonas aeruginosa and Malassezia pachydermatis F. BANOVIC, F. BOZIC and N. LEMO Faculty of Veterinary Medicine, Zagreb, Croatia The clinical severity of atopic dermatitis in human patients with secondary bacterial infections has been decreased with repeated dilute bleach baths and with intermittent intranasal application of mupirocin ointment. The aim of this study was to assess the in vitro antimicrobial efficacy of diluted sodium hypochlorite household bleach) with respect to clinical isolates of Staphylococcus pseudintermedius, Pseudomonas aeruginosa and Malassezia pachydermatis at two different exposure times. Ten isolates of each organism were incubated at 37C for 3 or 5 min with bleach working solution (0.05%) diluted 1:2 to 1:4096 in phosphate-buffered saline (PBS). Negative (bleach working solution only and sterile PBS only) and positive controls (microbial suspension in sterile PBS) were included. Aliquots were incubated at 37C for 1 day on sheep blood agar (bacteria) and for 3 days on Sabouraud’s dextrose agar Malassezia). The lowest dilutions exhibiting 100% antimicrobial efficacy against isolates were recorded. All isolates were completely killed by a dilution of 1:32 equivalent 0.00156% bleach) at both exposure times. The most susceptible micro-organism was P. aeruginosa, whose isolates were killed by 1:128 to 1:256 dilutions (equivalent 0.00039–0.00019% bleach). No significant difference was found in antimicrobial efficacy of diluted bleach between the two exposure times for all isolates. Based on these in vitro data for sodium hypochlorite, indicating antimicrobial activity, diluted bleach baths (0.003–0.007%) could be studied for the control of skin infections in dogs.

PHMB; sodium hypochlorite; chlorhexidine; dogs

nije evidentirano