title: Drug resistance profile and biofilm forming potential of Pseudomonas aeruginosa isolated from contact lenses in Karachi-Pakistan.
abstract: BACKGROUND
  The contaminated contact lens provides Pseudomonas aeruginosa an ideal site for attachment and biofilm production. Continuous contact of the eye to the biofilm-infested lens can lead to serious ocular diseases, such as keratitis (corneal ulcers). The biofilms also prevent effective penetration of the antibiotics, which increase the chances of antibiotic resistance.
  
  
  METHODS
  For this study, 22 Pseudomonas aeruginosa isolates were obtained from 36 contact lenses and 14 contact lens protective fluid samples. These isolates were tested against eight commonly used antibiotics using Kirby-Bauer disk diffusion method. The biofilm forming potential of these isolates was also evaluated using various qualitative and quantitative techniques. Finally, a relationship between biofilm formation and antibiotic resistance was also examined.
  
  
  RESULTS
  The isolates of Pseudomonas aeruginosa tested were found resistant to most of the antibiotics tested. Qualitative and quantitative biofilm analysis revealed that most of the isolates exhibited strong biofilm production. The biofilm production was significantly higher in isolates that were multi-drug resistant (p < 0.0001).
  
  
  CONCLUSIONS
  Our study indicates that multi-drug resistant, biofilm forming Pseudomonas aeruginosa isolates are mainly involved in contact lens associated infections. This appears to be the first report from Pakistan, which analyzes both antibiotic resistance profile and biofilm forming potential of Pseudomonas aeruginosa isolates from contact lens of the patients with contact lens associated infections.
authors.affiliation: Immunology and Infectious Diseases Research Lab, Department of Microbiology, University of Karachi, Karachi, Pakistan. m.haniabidi@gmail.com.
authors.forename: Syed H
authors.initials: SH
authors.lastname: Abidi
authors.forename: Sikandar K
authors.initials: SK
authors.lastname: Sherwani
authors.forename: Tarrunum R
authors.initials: TR
authors.lastname: Siddiqui
authors.forename: Asma
authors.initials: A
authors.lastname: Bashir
authors.forename: Shahana U
authors.initials: SU
authors.lastname: Kazmi
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D018441:Biofilms / Q000254:growth & development*; D018639:Contact Lens Solutions / Q000032:analysis; D003261:Contact Lenses / Q000382:microbiology*; D024901:Drug Resistance, Multiple, Bacterial; D006801:Humans; D008826:Microbial Sensitivity Tests; D010154:Pakistan; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000254:growth & development / Q000502:physiology*
chemical_list: D000900:Anti-Bacterial Agents; D018639:Contact Lens Solutions