Delayed-onset Endophthalmitis Associated with Conjunctival Filtering Blebs

Objective: The purpose of the study is to evaluate the causative organisms, treatment methods, and visual acuity outcomes of patients treated for delayed-onset endophthalmitis associated with conjunctival filtering blebs. Methods: The medical records of 32 patients with conjunctival filtering bleb-associated endophthalmitis treated at the Bascom Palmer Eye Institute between 1989 and 1995 were reviewed retrospectively. Bleb-associated endophthalmitis was diagnosed at 1 month or more after surgery in all patients. Patients with bleb infections only but without signs of intraocular infection were excluded from this series. Results: Previous antimetabolite therapy was used in 20 patients, including mitomycin C in 14 and 5-fluorouracil in 6. Streptococcal species were the most frequently cultured organisms occurring in 15 (47%) of 32 eyes. Of the 32 patients, 30 received intraocular antibiotics. The initial treatment included a pars plana vitrectomy in 18 patients and a vitreous tap without vitrectomy in 12 patients. Two of three patients who presented with no light perception vision were treated by evisceration. Overall, 15 (47%) of 32 patients achieved a final visual acuity of 201400 or better. Of those patients with Streptococcal species cultured from the eye, 6 (40%) of 15 had a visual acuity of 201400 or better compared to 9 (52%) of 17 in patients with non-Streptococcal species. Conclusions: Delayed-onset endophthalmitis associated with conjunctival filtering blebs is a current and future concern, especially with increasing use of mitomycin C. The Streptococcal species are a common causative organism. Despite current treatment of these patients, the visual acuity outcomes generally are worse than in patients with acute-onset endophthalmitis after cataract surgery.