Impact of antibiotic resistance in the management of ocular infections: the role of current and future antibiotics

Figures & data

Table 1 Prevalence of most common isolates from patients with bacterial conjunctivitis recovered within the 2-year period³¹

	1994–1995	1996–1997	1998–1999	2000–2001	2002–2003	Total
Gram-positive	166 (54.2%)	152 (56.5%)	128 (50.4%)	88 (47.6%)	121 (50.4%)	655 (52.5%)
Staphylococcus aureus	108 (65.0%)	114 (75.0%)	89 (69.5%)	69 (78.4%)	92 (76.0%)	472 (72.1%)
Streptococcus pneumoniae	18 (10.8%)	14 (9.2%)	21 (16.4%)	11 (12.5%)	16 (13.2%)	80 (12.2%)
Streptococcus viridans group	19 (11.6%)	6 (3.9%)	10 (7.8%)	6 (6.8%)	6 (5.0%)	47 (7.2%)
Gram-negative	140 (45.8%)	117 (43.5%)	126 (49.6%)	97 (52.4%)	119 (49.6%)	599 (47.8%)
Haemophilus influenzae	63 (45.0%)	53 (45.3%)	62 (49.2%)	50 (51.5%)	48 (40.3%)	276 (46.1%)
Pseudomonas aeruginosa	16 (11.4%)	8 (6.8%)	11 (8.7%)	5 (5.2%)	17 (14.3%)	57 (9.5%)
Proteus mirabilis	15 (10.7%)	8 (6.8%)	8 (6.3%)	3 (3.1%)	7 (5.9%)	41 (6.8%)

Figure 1 Percentage of S. aureus isolates resistant to methicillin (MRSA rate) according to specimen source (2000 to 2005 based on TSN database analysis). Reproduced with permission from Asbell PA, Sahm DF, Shaw M, Draghi DC, Brown NP. Increasing prevalence of methicillin resistance in serious ocular infections caused by Staphylococcus aureus in the United States: 2000 to 2005. J Cataract Refract Surg. 2008;34(5):814–818.²⁷ Copyright © 2008 Elsevier.

Figure 2 S. pneumoniae susceptibility in ocular isolates by drug from the Ocular Tracking Resistance in the U.S. Today (TRUST 1) longitudinal surveillance program, 1999 through 2006. Reproduced with permission from Asbell PA, Colby KA, Deng S, et al. Ocular TRUST: nationwide antimicrobial susceptibility patterns in ocular isolates. Am J Ophthalmol. 2008;145(6):951–958.²⁶ Copyright © 2008 Elsevier.

Table 2 Ocular pathogen susceptibility to topical antimicrobial agents (not shown: 36 nonpneumoniae streptococci, 39 miscellaneous)⁸⁹

Organism (No of isolates)	Percentage of resistant pathogensa
	Gati	Cipro	Oflox	Gent	Chloram
H. influenzae (83)	0	0	0	0	1.2
S. pneumoniae (70)	0	1.4	0	94.3	7.1
MSSA (123)	0.8	2.4	1.6	1.6	1.6
Enterobacteriaceae (60)	3.4	5.1	5.1	8.5	18.6
P. aeruginosa (38)	13.2	10.5	13.2	10.5	100
CoNS (48)	2.1	31.3	31.3	18.8	20.8
MRSA (35)	57.1	91.4	91.4	37.1	2.9

^a 532 ocular pathogens isolated from ocular infections from 2001 to 2002.

Abbreviations: Gati, gatifloxacin; Cipro, ciprofloxacin; Oflox, ofloxacin; Gent, gentamicin; Chloram, chloramphenicol; MSSA, methicillin-susceptible Staphylococcus aureus; CoNS, coagulase-negative Staphylococcus; MRSA, methicillin-resistant Staphylococcus aureus.

Table 3 MIC₉₀ values for besifloxacin against common causes of bacterial conjunctivitis^76,106

Bacterial strain	Besifloxacin: MIC90	Comparator(s): MIC90
Susceptible S. aureusa	0.03–0.5 μg/mL	N/A
Susceptible S. epidermidisa	0.03–0.5 μg/mL	N/A
Susceptible S. pneumoniaea	0.03–0.5 μg/mL	N/A
Susceptible H. influenzaea	0.03–0.5 μg/mL	N/A
MRSA	0.06 μg/mL	N/A
Vancomycin-intermediate S. aureus	2 μg/mL	N/A
Methicillin/ciprofloxacin-resistant S. aureus	8 μg/mL	N/A
Penicillin-resistant S. pneumoniae	0.12 μg/mL	N/A
Levofloxacin-resistant S. pneumoniae	2 μg/mL	N/A
H. influenzae with β-lactamase production	0.03 μg/mL	N/A
β-lactamase–positive, ampicillin-resistant H. influenzae	0.12 μg/mL	N/A
Ciprofloxacin-susceptible MSSA	0.06 μg/mL	Moxifloxacin: 0.125μg/mL Gatifloxacin: 0.25 μg/mL
Ciprofloxacin-resistant MSSA	2 μg/mL	Moxifloxacin: 8 μg/mL Gatifloxacin:>8 μ g/mL
Methicillin-susceptible S. epidermidis sensitive to ciprofloxacin	0.06 μg/mL	Moxifloxacin: 0.125μg/mL Gatifloxacin: 0.25 μg/mL
Methicillin-resistant S. epidermidis sensitive to ciprofloxacin	0.06 μg/mL	Moxifloxacin: 0.125μg/mL Gatifloxacin: 0.25 μg/mL
S. aureus parC S80Y + gyrA S84L double mutant	0.5 μg/mL	Moxifloxacin: 0.5μg/mL Ciprofloxacin: 32 μg/mL
S. pneumoniae parC S79Y + gyrA S81Y double mutant	1 μg/mL	Moxifloxacin: 4μg/mL Ciprofloxacin:64 μg/mL

^a Unpublished data Bausch & Lomb Inc.

Abbreviations: MRSA, methicillin-resistant Staphylococcus aureus; MSSA, methicillin-susceptible Staphylococcus aureus.

CavuotoKZutshiDKarpCLMillerDFeuerWUpdate on bacterial conjunctivitis in South FloridaOphthalmology20081151515617572497

 PubMed Web of Science ®Google Scholar

AsbellPASahmDFShawMDraghiDCBrownNPIncreasing prevalence of methicillin resistance in serious ocular infections caused by Staphylococcus aureus in the United States: 2000 to 2005J Cataract Refract Surg200834581481818471638

 PubMed Web of Science ®Google Scholar

AsbellPAColbyKADengSOcular TRUST: nationwide antimicrobial susceptibility patterns in ocular isolatesAm J Ophthalmol2008145695195818374299

 PubMed Web of Science ®Google Scholar

MorrisseyIBurnettRViljoenLRobbinsMSurveillance of the susceptibility of ocular bacterial pathogens to the fluoroquinolone gatifloxacin and other antimicrobials in Europe during 2001/2002J Infect200449210911415236917

 PubMed Web of Science ®Google Scholar

McDonaldMBBlondeauJMDeCoryHHMultidrug-resistant strains in clinical trials of besifloxacin in the treatment of bacterial conjunctivitisPresented at the American Academy of Ophthalmology Annual Meeting2008 Nov 8–11Atlanta, GA, USAPoster 070.

 Google Scholar

BrunnerLSNortonSEBlondeauJMIn vitro activity of SS734, a novel fluoroquinolone, against pathogens associated with bacterial conjunctivitis[poster] 17th European Congress of Clinical Microbiology and Infectious DiseasesMarch 31–April 3, 2007Munich, GermanyPoster P1679.

 Google Scholar