Antibiotic resistance of bacterial pathogens isolated from the conjunctiva in the Antibiotic Resistance Monitoring in Ocular micRoorganisms (ARMOR) surveillance study (2009-2021).

Antibiotic resistance in bacterial ocular infections is of significant clinical concern and may affect treatment outcomes. We report on in vitro antibiotic susceptibility rates and trends among conjunctival-sourced isolates collected in the Antibiotic Resistance Monitoring in Ocular micRoorganisms (ARMOR) surveillance study. A total of 2214 conjunctival isolates (918 Staphylococcus aureus, 589 coagulase-negative staphylococci [CoNS], 194 Streptococcus pneumoniae, 171 Pseudomonas aeruginosa, and 342 Haemophilus influenzae) obtained between 2009-2021 were analyzed.

Antibiotic susceptibility of bacterial pathogens isolated from the aqueous and vitreous humour in the Antibiotic Resistance Monitoring in Ocular micRoorganisms (ARMOR) Surveillance Study: 2009-2020 update.

Objectives: We evaluated antibiotic resistance among intraocular isolates obtained from presumed endophthalmitis cases collected from 2009 through 2020 in the Antibiotic Resistance Monitoring in Ocular micRoorganisms (ARMOR) study, the only ongoing nationwide surveillance study tracking in vitro resistance in ocular pathogens.

Methods: Presumed endophthalmitis isolates obtained from the aqueous humour and vitreous humour were collected from participating centres, and minimum inhibitory concentrations were determined and interpreted per Clinical and Laboratory Standards Institute methods and available breakpoints.

Results: A total of 307 presumed endophthalmitis isolates (aqueous humour, n = 88; vitreous humour, n = 219) were obtained from 43 clinical sites, including 188 coagulase-negative staphylococci (CoNS), 61 Staphylococcus aureus, 31 Streptococcus pneumoniae, 14 Pseudomonas aeruginosa, and 13 Haemophilus influenzae isolates.

Characterization of Polybacterial versus Monobacterial Conjunctivitis Infections in Pediatric Subjects Across Multiple Studies and Microbiological Outcomes with Besifloxacin Ophthalmic Suspension 0.6.

Introduction: The choice of empiric therapy for bacterial conjunctivitis should be guided by an awareness of typical causative pathogen distributions. Bacterial conjunctivitis can be polybacterial, although pediatric-specific data are lacking.

Methods: This was a post-hoc analysis of data in pediatric subjects (1-17 years) from five bacterial conjunctivitis trials evaluating besifloxacin ophthalmic solution 0.

Characterization of baseline polybacterial versus monobacterial infections in three randomized controlled bacterial conjunctivitis trials and microbial outcomes with besifloxacin ophthalmic suspension 0.6.

Background/purpose: To date, studies examining polymicrobial infections in ocular disease have mostly been limited to keratitis or endophthalmitis. We characterized polybacterial infections compared to monobacterial infections in prior clinical studies evaluating besifloxacin ophthalmic suspension 0.6% for the treatment of bacterial conjunctivitis and report on associated microbiological outcomes.

Trends in Antibiotic Resistance Among Ocular Microorganisms in the United States From 2009 to 2018.

Importance: Antibiotic resistance in ocular infections can affect treatment outcomes. Surveillance data on evolving antibacterial susceptibility patterns inform the treatment of such infections.

Objective: To assess overall antibiotic resistance profiles and trends among bacterial isolates from ocular sources collected during 10 years.

An Evaluation of Staphylococci from Ocular Surface Infections Treated Empirically with Topical Besifloxacin: Antibiotic Resistance, Molecular Characteristics, and Clinical Outcomes.

Introduction: Understanding antibiotic resistance and toxin profiles among staphylococcal isolates in ocular infections can aid in therapeutic management and infection prevention strategies. We evaluated in vitro antibiotic resistance patterns and molecular traits of staphylococci isolated from patients with ocular surface infections. We also report on clinical outcomes for these patients following empirical treatment with topical besifloxacin ophthalmic suspension 0.

Antibiotic Resistance Among Pediatric-Sourced Ocular Pathogens: 8-Year Findings From the Antibiotic Resistance Monitoring in Ocular Microorganisms (ARMOR) Surveillance Study.

Background: The Antibiotic Resistance Monitoring in Ocular Microorganisms (ARMOR) study is a nationwide longitudinal antibiotic resistance surveillance program specific to bacterial pathogens commonly encountered in ocular infections. We evaluated in vitro resistance rates and trends among isolates obtained from pediatric patients (≤17 years of age).

Methods: Clinical centers across the United States were invited to submit ocular isolates of Staphylococcus aureus, coagulase-negative staphylococci (CoNS), Streptococcus pneumoniae, Haemophilus influenzae and Pseudomonas aeruginosa to a central laboratory.

Antibiotic Resistance Rates by Geographic Region Among Ocular Pathogens Collected During the ARMOR Surveillance Study.

Introduction: The Antibiotic Resistance Monitoring in Ocular micRoorganisms (ARMOR) study is an ongoing nationwide surveillance program that surveys in vitro antibiotic resistance rates and trends among ocular bacterial pathogens. We report resistance rates by geographic region for isolates collected from 2009 through 2016.

Methods: Staphylococcus aureus, coagulase-negative staphylococci (CoNS), Streptococcus pneumoniae, Haemophilus influenzae, and Pseudomonas aeruginosa isolates from ocular infections were collected at clinical centers across the US and categorized by geographic region based on state.

Besifloxacin Ophthalmic Suspension 0.6% Compared with Gatifloxacin Ophthalmic Solution 0.3% for the Treatment of Bacterial Conjunctivitis in Neonates.

Purpose: The aim of this study was to evaluate the safety and efficacy of topical besifloxacin ophthalmic suspension 0.6% compared with gatifloxacin ophthalmic solution 0.3% in the treatment of bacterial conjunctivitis in neonates.

Besifloxacin: Efficacy and Safety in Treatment and Prevention of Ocular Bacterial Infections.

This comprehensive review summarizes the mechanism of action, pharmacokinetics, efficacy, and safety of besifloxacin ophthalmic suspension, 0.6% and examines its role in the treatment of ocular surface bacterial infections. Besifloxacin possesses balanced activity against bacterial topoisomerase II (also called DNA gyrase) and topoisomerase IV.

Antibiotic Resistance Among Ocular Pathogens in the United States: Five-Year Results From the Antibiotic Resistance Monitoring in Ocular Microorganisms (ARMOR) Surveillance Study.

Importance: The Antibiotic Resistance Monitoring in Ocular Microorganisms (ARMOR) study is the only ongoing nationwide antibiotic resistance surveillance program specific to ocular pathogens.

Objective: To report resistance rates and trends among common ocular isolates collected during the first 5 years of the ARMOR study.

Design, Setting, And Participants: This antibiotic resistance surveillance study was performed at an independent central laboratory.

Surveillance of the Activity of Aminoglycosides and Fluoroquinolones Against Ophthalmic Pathogens from Europe in 2010-2011.

Purpose/aim: Bacterial infections of the ocular surface are commonly treated empirically with broad spectrum antibiotics. Due to concerns over increasing antibiotic resistance, we evaluated current susceptibility patterns of the ocular bacterial pathogens in Europe.

Materials And Methods: Non-consecutive ocular isolates of Staphylococcus aureus, coagulase-negative staphylococci (CoNS), Streptococcus pneumoniae, Haemophilus influenzae, and Pseudomonas aeruginosa were collected in 2011 from centers in France, Germany, Italy, Poland, Slovak Republic, Spain, and the United Kingdom.

Antibacterial efficacy of prophylactic besifloxacin 0.6% and moxifloxacin 0.5% in patients undergoing cataract surgery.

Background: The purpose of this study was to investigate the ocular bacterial flora in patients scheduled to undergo cataract surgery and compare the antibacterial effects of besifloxacin ophthalmic suspension 0.6% and moxifloxacin ophthalmic solution 0.5% in these patients.

Unencapsulated Streptococcus pneumoniae from conjunctivitis encode variant traits and belong to a distinct phylogenetic cluster.

Streptococcus pneumoniae, an inhabitant of the upper respiratory mucosa, causes respiratory and invasive infections as well as conjunctivitis. Strains that lack the capsule, a main virulence factor and the target of current vaccines, are often isolated from conjunctivitis cases. Here we perform a comparative genomic analysis of 271 strains of conjunctivitis-causing S.

Contribution of the R8 substituent to the in vitro antibacterial potency of besifloxacin and comparator ophthalmic fluoroquinolones.

Introduction: Previous work has shown that besifloxacin, an 8-chloro-fluoroquinolone, has more potent activity against gram-positive pathogens than moxifloxacin and gatifloxacin, which carry an 8-methoxy group. This study was conducted to determine the contribution of the R7 and R8 substituent to fluoroquinolone antibacterial activity.

Materials And Methods: Besifloxacin, moxifloxacin, gatifloxacin, their R8 structural analogs, and ciprofloxacin were tested against representative isolates of various gram-positive and gram-negative species and previously characterized fluoroquinolone-resistant mutants of Staphylococcus aureus.

Microbiological etiology and susceptibility of bacterial conjunctivitis isolates from clinical trials with ophthalmic, twice-daily besifloxacin.

Introduction: Bacterial conjunctivitis is a contagious infection of the surface of the eye usually treated empirically with topical antibiotics. Since the etiologic agent is rarely identified, it is important to monitor which bacteria cause conjunctivitis and determine their antibacterial resistance profiles.

Methods: A total of 496 bacterial samples were isolated during a randomized, double-masked, vehicle-controlled, parallel-group study conducted in the United States with besifloxacin ophthalmic suspension 0.

Topoisomerase mutations that are associated with high-level resistance to earlier fluoroquinolones in Staphylococcus aureus have less effect on the antibacterial activity of besifloxacin.

Background: The impact of mutations in DNA gyrase and topoisomerase IV on minimum inhibitory concentrations (MICs) was investigated to better understand why besifloxacin has a higher potency against Staphylococcus aureus when compared to other fluoroquinolones, which was especially pronounced against ciprofloxacin-resistant isolates.

Methods: MICs were determined for 52 clinical isolates against besifloxacin, moxifloxacin, gatifloxacin, ciprofloxacin, and levofloxacin. The genes encoding GyrA, GyrB, ParC, and ParE were sequenced and the potential impact of mutations assessed in light of recent structural data.

High proportion of nontypeable Streptococcus pneumoniae isolates among sporadic, nonoutbreak cases of bacterial conjunctivitis.

Purpose: Outbreaks of bacterial conjunctivitis have been linked to nontypeable strains of Streptococcus pneumoniae that lack a capsule, a key virulence factor for invasive infections. In contrast, isolates from sporadic, nonoutbreak cases of conjunctivitis were thought to be similar to invasive or nasopharyngeal isolates with respect to their capsular serotype and antibiotic resistance profile. This hypothesis was tested for 302 strains isolated during three prospective, multicenter clinical studies of bacterial conjunctivitis.

In vitro time-kill experiments with besifloxacin, moxifloxacin and gatifloxacin in the absence and presence of benzalkonium chloride.

Objectives: To compare the bactericidal activity of besifloxacin, moxifloxacin and gatifloxacin and determine the contribution of the preservative benzalkonium chloride (BAK) to bactericidal activity.

Methods: Time-kill experiments were performed against four species (n=12) with besifloxacin, moxifloxacin and gatifloxacin, in the presence or absence of BAK, at t=0, 5, 15, 30, 45, 60, 120 and 360 min, according to standard CLSI methods.

Results: In the presence of BAK, bactericidal activity was observed within 5 min, regardless of the fluoroquinolone tested.

Molecular epidemiology of methicillin-resistant and methicillin-susceptible Staphylococcus aureus isolated from the eye.

Purpose: Methicillin-resistant Staphylococcus aureus (MRSA) strains are commonly classified as hospital-acquired (HA) or community-acquired (CA). Typical HA-MRSA isolates are characterized by multidrug resistance and the SCCmec type II cassette, while CA-MRSA isolates are generally susceptible to more drug classes, are often of SCCmec type IV, and frequently carry the Panton-Valentine leukocidin (PVL) genes. This study determined the presence of traits characteristic for CA and HA strains in ocular MRSA isolates.

Methamphetamine causes sustained depression in cerebral blood flow.

The use prevalence of the highly addictive psychostimulant methamphetamine (MA) has been steadily increasing over the past decade. MA abuse has been associated with both transient and permanent alterations in cerebral blood flow (CBF), hemorrhage, cerebrovascular accidents and death. To understand MA-induced changes in CBF, we exposed C56BL/6 mice to an acute bolus of MA (5mg/kg MA, delivered IP).

Comparison of besifloxacin, gatifloxacin, and moxifloxacin against strains of pseudomonas aeruginosa with different quinolone susceptibility patterns in a rabbit model of keratitis.

Purpose: Determine the effectiveness of topical besifloxacin, gatifloxacin, and moxifloxacin in treating keratitis caused by 2 strains of Pseudomonas aeruginosa with different quinolone susceptibility profiles.

Methods: Minimal inhibitory concentrations (MICs) were determined for each fluoroquinolone. Sequence analysis was performed on the quinolone resistance determining regions of the ciprofloxacin/levofloxacin-resistant strain.

Comparative efficacy of besifloxacin and other fluoroquinolones in a prophylaxis model of penicillin-resistant Streptococcus pneumoniae rabbit endophthalmitis.

Purpose: To study the efficacy of topical administration of gatifloxacin (0.3%), moxifloxacin (0.5%) ophthalmic solutions, and besifloxacin (0.