Infectious endophthalmitis: review of 420 cases

BACKGROUND To characterize the causative pathogens and the visual outcomes among patients with endophthalmitis at a large referral center in northeastern Thailand. METHODS All cases of infectious endophthalmitis treated between 1983 and 2007 were reviewed retrospectively. The patient data - including age, sex, history of ocular injuries, previous treatment and duration of the symptoms - were recorded. The ocular examination included affected side, anterior chamber reaction, vitreous haze, and presence of intraocular foreign bodies. Smears and cultures were prepared from anterior chamber paracentesis and/or vitreous tapping. Intraocular antibiotics were administered at the time of anterior chamber paracentesis and/or vitreous tapping. Vitrectomy and/or lensectomy were performed when indicated. Initial visual acuity before treatment and the final best-corrected vision were compared. RESULTS A total of 420 cases of endophthalmitis were reviewed: 181 cases (43.1%) had ocular trauma before the infection; 135 (32.2%) developed endophthalmitis after intraocular surgery; and, 122 (29.1%) had a positive culture. Bacteria were isolated in 114 cases (93.4%) and fungi were noted in eight (6.6%). The common causative bacterium was Staphylococcus epidermidis. Combined vitrectomy and intraocular antibiotics were performed in 189 cases (45.0%), whereas 69 cases (16.4%) were treated with intraocular antibiotics alone. CONCLUSION Most of the reviewed cases were associated with trauma and intraocular surgery. The most frequently encountered bacterium causing infectious endophthalmitis was S. epidermidis. Most cases were treated with combined vitrectomy and intraocular antibiotics. The final visual outcomes seem to vary according to the type of endophthalmitis.