title: Bacterial contamination of commercial ear cleaners following routine home use.
abstract: Ear cleaning solutions are designed for repeated use, which raises the possibility for bacterial contamination leading to recurrent or persistent infectious otitis. The purpose of this study was to investigate the prevalence of bacterial contamination of commercial ear cleaners following routine home use in dogs and to describe the characteristics that are associated with contamination. Used ear cleaner bottles and information regarding their use were obtained from canine owners visiting veterinary dermatologists. Both the bottle applicator tips and the solution contents were cultured for aerobic bacteria. Bacterial contamination was present on 10% of the bottle tips and in 2% of the solutions. Isolated bacteria included Staphylococcus pseudintermedius, Bacillus spp., coagulase-negative Staphylococcus spp., Micrococcus spp. and Burkholderia cepacia. The contamination rate was significantly higher on the applicator tips than in the solutions (P = 0.0076). The applicator tip contamination rate was significantly higher in expired samples (17%) than in-date samples (4%; P = 0.0277). The bottle sizes were significantly larger for the samples with contaminated applicator tips compared with noncontaminated tips (P = 0.0455). The contamination rate was significantly higher when Tris-EDTA was an ingredient. Cleanliness of the bottle, contact with the ear canal and infection status of the ear at time of culture had no bearing on the contamination rate. In summary, with routine home use of commercial ear cleaners, pathogenic bacterial contamination is of minor concern. This concern may increase when expired products or larger bottles of ear cleaner are used and when Tris-EDTA is an ingredient.
authors.affiliation: Animal Dermatology Clinic, Marietta, GA 30062, USA. sbartlett@adcmg.com
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: Bartlett
authors.forename: Wayne S
authors.initials: WS
authors.lastname: Rosenkrantz
authors.forename: Susan
authors.initials: S
authors.lastname: Sanchez
mesh_terms: D000818:Animals; D000891:Anti-Infective Agents, Local / Q000627:therapeutic use; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use; D001407:Bacillus / Q000302:isolation & purification; D016956:Burkholderia cepacia / Q000302:isolation & purification; D058113:Cerumenolytic Agents / Q000627:therapeutic use; D002614:Chelating Agents; D004283:Dog Diseases / Q000188:drug therapy* / Q000382:microbiology; D004285:Dogs; D004349:Drug Packaging; D004492:Edetic Acid; D004866:Equipment Contamination / Q000706:statistics & numerical data*; D008837:Micrococcus / Q000302:isolation & purification; D010032:Otitis Externa / Q000188:drug therapy / Q000382:microbiology / Q000662:veterinary*; D019999:Pharmaceutical Solutions / Q000627:therapeutic use*; D013210:Staphylococcus / Q000302:isolation & purification; D013501:Surface-Active Agents / Q000627:therapeutic use
chemical_list: D000891:Anti-Infective Agents, Local; D000893:Anti-Inflammatory Agents; D058113:Cerumenolytic Agents; D002614:Chelating Agents; D019999:Pharmaceutical Solutions; D013501:Surface-Active Agents; D004492:Edetic Acid