Susceptibility trends of Pseudomonas species from corneal ulcers

Abstract

Purpose: To assess the changing trends in the antibiotic susceptibility of Pseudomonas spp. isolated from bacterial keratitis over a nine year period with special emphasis on fluoroquinolone susceptibilities. Methods: All corneal scraping cultures positive for Pseudomonas spp. (n=585) isolated from patients with bacterial keratitis at the Aravind Eye Hospital, Madurai from1995-2003 were evaluated. Cultures were performed in liquid and solid media and susceptibility testing was done against amikacin, gentamicin, tobramycin, ciprofloxacin and ofloxacin by Kirby-Bauer disc diffusion method. Results: The susceptibility of Pseudomonas spp. was over 90% from 1995-1998 to ciprofloxacin which decreased to 83% from 1999-2003. The total number of isolates resistant to ciprofloxacin was 51(9.4%). No statistically significant increase in the number of isolates resistant to ciprofloxacin was noted. Ofloxacin showed 54% susceptibility from 1995-1998 but increased to 64% from 1999-2003. Analysis of in vitro activity of amikacin reveals that there was 43% sensitivity from 1995-1998 but later it increased to 76% from 1999-2003. In case of gentamicin, the sensitivity decreased marginally from 80% to 70% through the years. Tobramycin showed 45% sensitivity from 1995-1998 but increased to 75% from 1999-2003. Conclusions: The fluoroquinolones remain a good choice in the treatment of ocular infections, with high susceptibility of Pseudomonas spp. Among the aminoglycosides, gentamicin was found to be highly effective against Pseudomonas corneal ulcers when compared to amikacin and tobramycin. The results show a need for continuous monitoring of bacterial resistance trends.

Antibiotic susceptibility patterns of Pseudomonas aeruginosa at a tertiary care hospital in Gujarat, India

“…[18] Amikacin was designed as a poor substrate for the enzymes that bring about inactivation by phosphorylation, adenylation or acetylation, but some organisms have developed enzymes that inactivate this agent as well. Amikacin seems to be a promising therapy for Pseudomonal infection.…”

Characterization of Ocular Clinical Isolates of Pseudomonas aeruginosa from Non-Contact Lens Related Keratitis Patients from South India

“…Subedi et al reported that levofloxacin, ciprofloxacin and amikacin were the most effective drugs for ocular infections [23]. They found that the antibiotic resistance rates in ocular isolates have been stable [24] however, a recent report from Das et al found a significant decrease in susceptibility in Pseudomonas spp. isolated from keratitis patients to a fourth generation fluoroquinolone, moxifloxacin [25], suggesting a rise in antibiotic resistance in Pseudomonas spp.…”

Susceptibilidade antibiótica de isolados bacterianos em diferentes tipos de ceratites ulcerativas de cães na cidade de Cuiabá

“…Com base em cultura e antibiograma, antibióticos específicos podem ser recomendados. Em humanos com ceratite ulcerativa reportou-se que o ciprofloxacino e a gentamicina apresentaram maior eficácia contra P. aeruginosa, quando comparados à amicacina e a tobramicina (Lalitha et al 2005). O ciprofloxacino também se mostrou mais eficaz que outros antibióticos contra esse agente, em cães com ceratite ulcerativa em Taiwan (Lin & Petersen-Jones, 2007), nos Estados Unidos (Ledbetter et al 2007), na China (Wang et al 2008), na Austrália (Hindley et al 2016) e na Inglaterra (Everson et al 2016).…”