Activity of newer fluoroquinolones against gram-positive and gram-negative bacteria isolated from ocular infections: An <i> in vitro</i> comparison
<b>Background: </b> To determine the antibacterial activity of newer fluoroquinolones and compare their activity between ciprofloxacin-susceptible and resistant bacterial isolates from patients with keratitis and endophthalmitis<i> .</i> <b> Materials and Methods:</...
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| Format: | Article |
| Language: | English |
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Wolters Kluwer Medknow Publications
2007-01-01
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| Series: | Indian Journal of Ophthalmology |
| Subjects: | |
| Online Access: | http://www.ijo.in/article.asp?issn=0301-4738;year=2007;volume=55;issue=1;spage=15;epage=19;aulast=Duggirala |
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| author | Duggirala Aparna Joseph Joveeta Sharma Savitri Nutheti Rishita Garg Prashant Das Taraprasad |
| author_facet | Duggirala Aparna Joseph Joveeta Sharma Savitri Nutheti Rishita Garg Prashant Das Taraprasad |
| author_sort | Duggirala Aparna |
| collection | DOAJ |
| description | <b>Background: </b> To determine the antibacterial activity of newer fluoroquinolones and compare their activity between ciprofloxacin-susceptible and resistant bacterial isolates from patients with keratitis and endophthalmitis<i> .</i> <b> Materials and Methods:</b> The minimum inhibitory concentration (MIC) of ciprofloxacin, ofloxacin, levofloxacin, gatifloxacin and moxifloxacin was determined for 123 bacterial isolates, using E test<i> .</i> Among the 123 isolates, 68 were gram-positive (<i> Staphylococcus</i> spp, <i> Streptococcus</i> spp, <i> Corynebacterium</i> spp, <i> Bacillus </i> spp.) and 55 were gram-negative (<i> Pseudomonas aeruginosa)</i> . The bacterial isolates were divided into three groups: susceptible / intermediate/ resistant to ciprofloxacin. The MIC values for various fluoroquinolones were compared between the three groups and between gram-positive and gram-negative bacteria. <b> Results:</b> For gram-positive isolates, median MICs of fourth generation fluoroquinolones were lower than second generation. The median MIC was lowest for gatifloxacin and moxifloxacin (0.094 mg/ml) in ciprofloxacin-susceptible isolates of gram-positive bacteria. For ciprofloxacin-susceptible gram-negative bacteria, the median MIC of ciprofloxacin (0.19 mg/ml) was significantly lower than ofloxacin, levofloxacin, gatifloxacin and moxifloxacin (1.5, 0.5, 0.5 and 2 mg/ml respectively). Ciprofloxacin-resistant isolates of gram-positive bacteria showed higher MIC of levofloxacin, moxifloxacin and gatifloxacin though they remained susceptible to them. None of the fluoroquinolones were effective against ciprofloxacin-resistant gram-negative bacteria. Overall, for gram-positive bacteria, median MICs of levofloxacin, moxifloxacin and gatifloxacin were below ciprofloxacin, the MIC of gatifloxacin and moxifloxacin was equal for gram-positive bacteria. <b> Conclusions:</b> Levofloxacin, gatifloxacin and moxifloxacin are statistically more effective against gram-positive bacteria, the latter two being equally effective. Ciprofloxacin remains the most effective fluoroquinolone against gram-negative bacteria. |
| first_indexed | 2024-12-23T05:46:18Z |
| format | Article |
| id | doaj.art-94364c8a3e344086a4e12b8e7f04100d |
| institution | Directory Open Access Journal |
| issn | 0301-4738 |
| language | English |
| last_indexed | 2024-12-23T05:46:18Z |
| publishDate | 2007-01-01 |
| publisher | Wolters Kluwer Medknow Publications |
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| series | Indian Journal of Ophthalmology |
| spelling | doaj.art-94364c8a3e344086a4e12b8e7f04100d2022-12-21T17:58:06ZengWolters Kluwer Medknow PublicationsIndian Journal of Ophthalmology0301-47382007-01-015511519Activity of newer fluoroquinolones against gram-positive and gram-negative bacteria isolated from ocular infections: An <i> in vitro</i> comparisonDuggirala AparnaJoseph JoveetaSharma SavitriNutheti RishitaGarg PrashantDas Taraprasad<b>Background: </b> To determine the antibacterial activity of newer fluoroquinolones and compare their activity between ciprofloxacin-susceptible and resistant bacterial isolates from patients with keratitis and endophthalmitis<i> .</i> <b> Materials and Methods:</b> The minimum inhibitory concentration (MIC) of ciprofloxacin, ofloxacin, levofloxacin, gatifloxacin and moxifloxacin was determined for 123 bacterial isolates, using E test<i> .</i> Among the 123 isolates, 68 were gram-positive (<i> Staphylococcus</i> spp, <i> Streptococcus</i> spp, <i> Corynebacterium</i> spp, <i> Bacillus </i> spp.) and 55 were gram-negative (<i> Pseudomonas aeruginosa)</i> . The bacterial isolates were divided into three groups: susceptible / intermediate/ resistant to ciprofloxacin. The MIC values for various fluoroquinolones were compared between the three groups and between gram-positive and gram-negative bacteria. <b> Results:</b> For gram-positive isolates, median MICs of fourth generation fluoroquinolones were lower than second generation. The median MIC was lowest for gatifloxacin and moxifloxacin (0.094 mg/ml) in ciprofloxacin-susceptible isolates of gram-positive bacteria. For ciprofloxacin-susceptible gram-negative bacteria, the median MIC of ciprofloxacin (0.19 mg/ml) was significantly lower than ofloxacin, levofloxacin, gatifloxacin and moxifloxacin (1.5, 0.5, 0.5 and 2 mg/ml respectively). Ciprofloxacin-resistant isolates of gram-positive bacteria showed higher MIC of levofloxacin, moxifloxacin and gatifloxacin though they remained susceptible to them. None of the fluoroquinolones were effective against ciprofloxacin-resistant gram-negative bacteria. Overall, for gram-positive bacteria, median MICs of levofloxacin, moxifloxacin and gatifloxacin were below ciprofloxacin, the MIC of gatifloxacin and moxifloxacin was equal for gram-positive bacteria. <b> Conclusions:</b> Levofloxacin, gatifloxacin and moxifloxacin are statistically more effective against gram-positive bacteria, the latter two being equally effective. Ciprofloxacin remains the most effective fluoroquinolone against gram-negative bacteria.http://www.ijo.in/article.asp?issn=0301-4738;year=2007;volume=55;issue=1;spage=15;epage=19;aulast=DuggiralaFluoroquinolonesgram-negative bacteriagram-positive bacteriaminimum inhibitory concentration. |
| spellingShingle | Duggirala Aparna Joseph Joveeta Sharma Savitri Nutheti Rishita Garg Prashant Das Taraprasad Activity of newer fluoroquinolones against gram-positive and gram-negative bacteria isolated from ocular infections: An <i> in vitro</i> comparison Indian Journal of Ophthalmology Fluoroquinolones gram-negative bacteria gram-positive bacteria minimum inhibitory concentration. |
| title | Activity of newer fluoroquinolones against gram-positive and gram-negative bacteria isolated from ocular infections: An <i> in vitro</i> comparison |
| title_full | Activity of newer fluoroquinolones against gram-positive and gram-negative bacteria isolated from ocular infections: An <i> in vitro</i> comparison |
| title_fullStr | Activity of newer fluoroquinolones against gram-positive and gram-negative bacteria isolated from ocular infections: An <i> in vitro</i> comparison |
| title_full_unstemmed | Activity of newer fluoroquinolones against gram-positive and gram-negative bacteria isolated from ocular infections: An <i> in vitro</i> comparison |
| title_short | Activity of newer fluoroquinolones against gram-positive and gram-negative bacteria isolated from ocular infections: An <i> in vitro</i> comparison |
| title_sort | activity of newer fluoroquinolones against gram positive and gram negative bacteria isolated from ocular infections an i in vitro i comparison |
| topic | Fluoroquinolones gram-negative bacteria gram-positive bacteria minimum inhibitory concentration. |
| url | http://www.ijo.in/article.asp?issn=0301-4738;year=2007;volume=55;issue=1;spage=15;epage=19;aulast=Duggirala |
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