In vitro Susceptibilities of Methicillin-Susceptible and Resistant Staphylococci to Traditional Antibiotics Compared to a Novel Fluoroquinolone.

BACKGROUND: To assess the in-vitro efficacy of delafloxacin, a new fourth generation fluoroquinolone, against Staphylococcus vitreous isolates from patients with clinically diagnosed endophthalmitis. This is the first investigation of delafloxacin in ocular tissues. METHODS: Intravitreal isolates of culture-proven S. aureus and S. epidermidis were identified between 2014 and 2018. Minimum inhibitor concentrations (MIC) were determined using ETEST strips. The antibiotic susceptibilities were tested against a panel of drugs including glycopeptides such as vancomycin, as well as traditional and newer fluoroquinolones (levofloxacin, moxifloxacin, and delafloxacin). RESULTS: Of 45 total isolates identified between 2014 and 2018, 13% (6) were methicillin-resistant S. aureus (MRSA), 9% (4) were methicillin-sensitive S. aureus (MSSA), 53% (24) were methicillin-resistant S. epidermidis (MRSE), and 24% (11) were methicillin-sensitive S. epidermidis (MSSE). Among the fluoroquinolones, resistance rates were 61% for levofloxacin, 50% for moxifloxacin, and 12% for delafloxacin. Inter-class comparisons between delafloxacin and the two other fluoroquinolones demonstrated higher Gram-positive susceptibility to delafloxacin (p < 0.01). MIC90 values were lowest for delafloxacin (1.0 µg/mL) compared to levofloxacin (8.0 µg/mL) and moxifloxacin (8.0 µg/mL). Vancomycin was 100% effective against all isolates with MIC90 value of 0.75 µg/mL. CONCLUSION: Compared to levofloxacin and moxifloxacin, the newer fluoroquinolone delafloxacin demonstrated the lowest MICs values and lowest rates of resistance for Gram-positive in-vitro S. epidermidis and S. aureus vitreous isolates.

Treatment of earlobe keloids using the cobalt 60 teletherapy unit.

The purpose of this study was to develop an easily accessible technique for the delivery of postoperative radiotherapy for the treatment of earlobe keloids. Forty-seven earlobe keloids were given postoperative radiation using the smallest achievable half field Telecobalt technique. Results showed 41 (87.2%) of treated patients' postoperative scars remained free from recurrent keloid formation. Acute reactions were minimal and patient compliance was excellent. In conclusion, the technique described in this study for the delivery of postoperative radiation to earlobe keloids should be readily available in areas of high prevalence. Results are comparable to previously used radiotherapy techniques.