Ciprofloxacin susceptibility of Pseudomonas aeruginosa isolates from keratitis
Open Access
- 1 October 2003
- journal article
- research article
- Published by BMJ in British Journal of Ophthalmology
- Vol. 87 (10), 1238-1240
- https://doi.org/10.1136/bjo.87.10.1238
Abstract
Aim: To examine the ciprofloxacin susceptibility of 106 Pseudomonas aeruginosa eye isolates from the United Kingdom, Denmark, India, the United States, and Australia, and to determine the molecular mechanisms of resistance. Methods: Ciprofloxacin susceptibility was tested by an agar dilution method; genomic DNA corresponding to the quinolone target genes gyrA and parC, and the regulatory genes mexR and nfxB controlling drug efflux systems, was amplified by PCR and sequenced; multilocus enzyme electrophoresis was performed to examine the genetic relation among resistant strains. Results: Three out of 90 keratitis isolates (3.3%), one from the United Kingdom and two from India, exhibited MIC values of 16 mg/l or 32 mg/l. The UK isolate had a mutation in gyrA (Thr83Ile), whereas the two Indian isolates showed mutations in both gyrA (Thr83Ile) and parC (Ser87Leu). The remaining isolates from keratitis, endophthalmitis, contact lens associated red eye (CLARE), and contact lens storage cases showed MIC values below 1 mg/l. Several allelic forms of gyrA and a single variation in the mexR gene product were detected in 10 ciprofloxacin susceptible strains. Conclusions: The vast majority of eye isolates of P aeruginosa from European countries are fully susceptible to ciprofloxacin and the concentration of ciprofloxacin eye drops used for local treatment (3000 mg/l) exceeds MIC values for strains recorded as resistant. Mutations in more than one target gene were associated with higher MIC values.Keywords
This publication has 17 references indexed in Scilit:
- Fourth generation fluoroquinolones: new weapons in the arsenal of ophthalmic antibiotics11The Eye and Ear Foundation of Pittsburgh (Pittsburgh, PA) was given a core grant for Vision Research EY 08098 and Research to Prevent Blindness. The first author (R.M.) was granted travel support for ARVO 2001 in Fort Lauderdale, FL by Alcon (Fort Worth, TX).American Journal of Ophthalmology, 2002
- Detection of Ciprofloxacin-Resistant Yersinia pestis by Fluorogenic PCR Using the LightCyclerJournal of Clinical Microbiology, 2001
- Epidemic Population Structure of Pseudomonas aeruginosa : Evidence for a Clone That Is Pathogenic to the Eye and That Has a Distinct Combination of Virulence FactorsInfection and Immunity, 2001
- Type II Topoisomerase Mutations in Fluoroquinolone-Resistant Clinical Strains of Pseudomonas aeruginosa Isolated in 1998 and 1999: Role of Target Enzyme in Mechanism of Fluoroquinolone ResistanceAntimicrobial Agents and Chemotherapy, 2001
- Molecular Mechanisms of Fluoroquinolone Resistance in Pseudomonas aeruginosa Isolates from Cystic Fibrosis PatientsAntimicrobial Agents and Chemotherapy, 2000
- Prolonged persistence on the ocular surface of fortified gentamicin ointment as compared to fortified gentamicin eye dropsActa Ophthalmologica Scandinavica, 2000
- Study of the First Contact Management Profile of Cases of Infectious Keratitis: A Hospital-Based StudyCornea, 2000
- Emerging ciprofloxacin-resistant Pseudomonas aeruginosaAmerican Journal of Ophthalmology, 1999
- Pseudomonas aeruginosa isolated from corneal ulcer: susceptibility to antimicrobial agents tested alone or in combination.1992
- Insights from experimental data on ciprofloxacin in the treatment of bacterial keratitis and ocular infections.1991