Of the 730 pediatric subjects with culture-confirmed
conjunctivitis, nearly one-fourth (23.6%) had polybacterial
infections and three-fourths (76.4%) had monobacterial
infections at baseline. In both polybacterial and monobacterial
infections, the most prevalent organisms were Haemophilus influenzae, Streptococcus pneumoniae, Staphylococcus aureus, and Streptococcus mitis/S. mitis group. In polybacterial versus monobacterial
infections, S. mitis/S. mitis group (8.7% vs 4.3%; P=0.032) and Moraxella catarrhalis (4.7% vs 0.5%; P<0.001) were identified more frequently, whereas S. pneumoniae (14.0% vs 28.1%; P<0.001) was identified less frequently, as the dominant infecting species. MICs for individual species were similar for tested
antibiotics regardless of polybacterial or monobacterial
infection, except Staphylococcus epidermidis for which
fluoroquinolone MICs were ≥3 dilutions higher for isolates of this species sourced from polybacterial compared to monobacterial
infections. Treatment with
besifloxacin resulted in microbial eradication in 79.1% of polybacterial and 92.3% of monobacterial
infections (P≤0.005 vs vehicle).
DISCUSSION: