Resumen

Introduction: We aimed to investigate the susceptibility of a combined inoculum of Pseudomonas aeruginosa and different fungal strains to 6 soft contact lens disinfectants. Methodology: One corneal isolate of P. aeruginosa and 13 corneal fungal isolates (9 Aspergillus spp, 3 Fusarium spp, 1 Curvularia sp.) were used. The following solutions were tested: Arion Cronos, Complete RevitaLens, Dua Elite, Opti-Free Express, Regard, Oxysept Comfort, and Oxysept Comfort without catalase. The effect of the solutions was assessed on a combined inoculum of P. aeruginosa plus 1 fungal strain. Suspensions of P. aeruginosa and fungi were made in the solutions (1x106 colony-forming units/mL). After 1 hour (Arion Cronos only), 6, 8, and 24 hours, aliquots of suspension were removed and seeded on Luria-Bertani and Sabouraud agar plates. Results: After 6 hours’ exposure, all the solutions but Dua Elite and Oxysept Comfort eradicated P. aeruginosa. Conversely, apart from 3% hydrogen peroxide-based Oxysept Comfort without catalase, which eradicated all the fungi tested after 6 hours, all the other solutions were partly ineffective at killing some of the fungal isolates, even after 24 hours’ exposure. Conclusions: Most contact lens disinfectants may be ineffective if contact lens care systems become co-contaminated with P. aeruginosa and fungi. In our experiment, only exposure to 3% hydrogen peroxide without neutralizer for at least 6 hours was always able to kill a combined inoculum of P. aeruginosa and different fungal strains.

Palabras clave: Contact lens-related keratitis; contact lens disinfectants; filamentous fungi; Pseudomonas aeruginosa; co-culture; susceptibility.

2013-03-15   |   522 visitas   |   Evalua este artículo 0 valoraciones

Vol. 7 Núm.3. Marzo 2013 Pags. 261-268 J Infect Developing Countries 2013; 7(3)