[Determination of causative agents in ocular infection of external adnexa and anterior segments--multicenter study of causative agents and drug sensitivity of ocular infection by the Japanese Association for Ocular Infection part I].

PURPOSE

To determine the causative agents of ocular infection of external adnexa and anterior segments due to selected criteria.

SUBJECTS AND METHODS

Between September 22, 2007 and August 25, 2008, 890 bacterial strains were collected from 476 patients in 18 facilities nationwide participating in the Drug Sensitivity for Ocular Infection Study Group. Usual aerobic and anaerobic cultures, enrichment cultures, smears, and measurements of bacterial quantity were performed and the determination of causative agents was made from the results of smears and culture, the presence of polymorphonuclear cells and bacterial quantity. The selection was divided into two categories, causative agents and presumed causative agents. Staphylococcus aureus, Moraxella bacilli, Haemophilus influenzae, Streptococcus pneumoniae, Pseudomonas aeruginosa, and Neisseria gonorrhoeae were distinctively considered as specified bacteria.

RESULTS

Among 890 strains, 18.8% were determined to be causative agents, and 15.1% were determined to be presumed causative agents. Among the bacteria detected in normal flora, 2.0% of Staphylococcus epidermidis, 2.6% of Propionibacterium acnes, and 38.3% of Corynebacterium spp. were determined to be causative agents.

CONCLUSION

To determine the causative agents, the results of smears and bacterial quantity should be considered together with culture results. Bacteria constituting normal flora have the potential of becoming causative agents.