Purpose To analyze the clinical characteristics and treatment outcomes of pati ents with bleb-associated endophthalmitis (BAE). Design Retrospective, non comp arative, interventional case series. Participants Consecutive patients treated a t one institution for BAE. Interventions Prompt pars plana vitrectomy (PPV) with intravitreal injection of antibiotics, or prompt vitreous biopsy and intravitre al injection of antibiotics (tap and inject). Methods Retrospective analysis of 68 consecutive cases of BAE between July 1, 1989 and June 30, 2001. Clinical pre sentation, treatment modality, microbiologic data, and clinical course were anal yzed. Visual outcomes were compared between vitrectomy and tap-and-inject grou ps, culture-positive and culture-negative groups, and early and late times. Ma in outcome measures Snellen visual acuities (VAs) at 3 months and 12 months afte r treatment and at most recent follow-up. Results The incidence of no light per ception (NLP) at 12 months after treatment for BAE was 35%. Vitreous isolates i ncluded streptococcal species (32%of positive cultures), Staphylococcus epiderm idis (26%), Enterococcus, and Serratia (12%each). Patients with a positive vit reous culture had significantly worse VA (median, hand movements HM at 3 and 1 2 months after treatment) and a higher rate of NLP vision. Patients treated with tap-and-inject had a significantly worse final VA (medians, HM at 3 months an d LP at 12 months) and a significantly higher rate of NLP vision than patients t reated with PPV. One third of patients who underwent PPV achieved a final VA of 20/100 or better 12 months after treatment (P=0.09). Conclusions Bleb associated endophthalmitis causes significant visual morbidity. Patients with culture-neg ative BAE and patients treated with prompt PPV may achieve better visual outcome . Purpose To analyze the clinical characteristics and treatment outcomes of pati ents with bleb-associated endophthalmitis (BAE). Design Retrospective, non comprative, interventional case series. Participants Consecutive patients treated at one institution for BAE. Interventions Prompt pars plana vitrectomy (PPV) with intravitreal injection of antibiotics, or prompt vitreous biopsy and intravitre al injection of antibiotics (tap and inject). Methods Retrospective analysis of 68 consecutive cases of BAE between July 1, 1989 and June 30, 2001. Clinical pre sentation, treatment modality, microbiologic data, and clinical course were anal yzed. Visual outcomes were compared between vitrectomy and tap-and-inject grou ps, culture-positive and culture-negative groups, and early and late times. Ma in outcome measures Snellen visual acuities (VAs) at 3 months and 12 months afte r treatment and at most recent follow-up. Results The incidence of no light per ception (NLP) at 12 months after treat Strain of BAE was 35%. Vitreous isolates were not streptococcal species (32% of positive cultures), Staphylococcus epiderm idis (26%), Enterococcus, and Serratia (12% each). Patients with a positive vit reous culture had significantly worse VA (median, hand movements HM at 3 and 1 2 months after treatment) and a higher rate of NLP vision. Patients treated with tap-and-injected had a significantly worse final VA (medians, HM at 3 months an d LP at 12 months ) and a significantly higher rate of NLP vision than patients t reated with PPV. One third of patients who underwent PPV achieved a final VA of 20/100 or better 12 months after treatment (P = 0.09). Conclusions Bleb associated endophthalmitis causes significant visual morbidity. Patients with culture-neg ative BAE and patients treated with prompt PPV may achieve better visual outcome.