1. Ocular infections due to pseudomonas resistant to fourth-generation fluoroquinolones The authors have no financial interest in the subject matter of this poster
Heloisa Nascimento, Aline Silveira Moriyama, Denise de Freitas, Ana Luisa Höfling-Lima
Departmet of Ophthalmology Federal University of São Paulo São Paulo, Brazil

2. Background Pseudomonas aeruginosa Gram negative bacillus
Important keratitis agent
Traditionally associated to CL wear
Aggressive infection
P. aeruginosa
Increasing rates of fluoroquinolone resistance
More virulent than fluoroquinolone sensible strains
More prevalent among non-CL weares Pseudomonas infections

3. Purpose
To report the prevalence of fourth-generation fluoroquinolones resistance among Pseudomonas aeruginosa isolates from patients with keratitis at the Laboratory of Ocular Microbiology of the Federal University of São Paulo.

4. Methods
Retrospective review of data from patients with keratitis who had cornea specimen sent to microbiological analysis at the Laboratory of Ocular Microbiology of the Federal University of São Paulo (UNIFESP) during the seven years period between July, 2002 and July, 2009
Patients whose exam confirmed P. aeruginosa were included in the study. Cases with identification of other Pseudomonas species or Pseudomonas spp were not included
P. aeuruginosa isolates with resistance to any of the tested fourth-generation fluoroquinolone were selected and evaluated regarding antimicrobial susceptibility profile

5. P. aeruginosa keratitis
Results
Rates of culture proven P. aeruginosa keratitis per year and proportion of cases with resistance to fourth-generation fluoroquinolones
Year
P. aeruginosa keratitis
P. aeruginosa fourth-generation fluoroquinolone resistant keratits
2002 6
2003 28
2004 10
2005 12
1 (8,33%)
2006 8
1 (12,5%)
2007 11
1 (9,09%)
2008
2009 13
6 (46,15%)
Overall
100
10 (10%)

6. Results
Profile and associated ocular and systemic conditions of the P. aeruginosa isolates resistant to fourth-generation fluoroquinolones
Case #
Year
Gender
Age
Associated conditions 1
2005 M
Contact Lens Wear 2
2006 F 67
Carcinomatosis 3
2007 63
Sepsis - ICU 4
2008 5
2009 40
Respiratory Insufficiency - ICU 6 37
Chemical ocular injury 7 47
Previous PPV 8
Corneal Ulcer 9 39
Corneal FB removal and TCL+ofloxacyn use 10
Corneal ulcer

7. Results
Antimicrobial susceptibility profile of the P. aeruginosa isolates resistant to fourth-generation fluoroquinolones

8. Conclusion
It is the first time Pseudomonas aeruginosa resistance to fourth-generation fluoroquinolone is noted in Brazil
Increasing rates of fourth-generation fluoroquinolones resistance in Brazil after moxifloxacin and gatifloxacin eye drops became commercially available (2004)
Pick prevalence of 46,15% P. aeruginosa strains resistant to fourth-generation fluoroquinolones among P. aeruginosa keratitis is alarming, with practical implications on empiric treatment to Pseudomonas keratits suspects
Continued microbiological surveillance is essential

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