Delayed-onset bleb-associated endophthalmitis: clinical features and visual acuity outcomes.

OBJECTIVE

To investigate clinical factors, causative organisms, treatments, and visual acuity and intraocular pressure outcomes associated with delayed-onset, bleb-associated endophthalmitis.

DESIGN

Retrospective, noncomparative, consecutive case series.

PARTICIPANTS

All patients treated for bleb-associated endophthalmitis at Bascom Palmer Eye Institute between January 1, 1996, and July 1, 2001. All patients had prior glaucoma filtering surgery. Patients with inadvertent functioning blebs after cataract extraction were excluded.

MAIN OUTCOME MEASURES: Visual acuity outcomes and intraocular pressure control after endophthalmitis.

RESULTS

An antifibrotic agent was used in 40 (82%) of the 49 eyes identified, including mitomycin-C in 33 (67%) and 5-fluorouracil (5-FU) in 7 (14%). The mean interval between the initial filtering surgery and endophthalmitis diagnosis was 5.0 years (range, 0.7-12.2 years). The mean follow-up time after treatment for endophthalmitis was 6.9 months (range, 1-60 months). As recorded in the medical record, potential risk factors and clinical features among the study population included history of bleb leak in 13 (27%) eyes, bleb manipulations in 15 (31%) (needling in 3 [6%], compression sutures in 2 [4%], laser suture lysis in 6 [12%], bleb revision in 5 [10%], and autologous blood injection in 2 [4%]), bleb defects in 6 (12%), inferior bleb location 6 (12%), and nasolacrimal duct obstruction in 1 (2%). The most common causative organisms were Streptococcus species in 15 eyes (31%) and Staphylococcus species in 11 eyes (22%). Final visual acuities in the vitrectomy group (n = 22) versus the initial tap group (n = 26) were as follows: > or = 20/40 (5% versus 15%), 20/50 to 20/400 (32% versus 54%), and < 5/200 (64% versus 31%). Eleven (22%) patients eventually underwent enucleation or evisceration secondary to pain and/or poor vision (light perception to no light perception). In 4 (11%) of the 38 eyes not enucleated, intraocular pressures were poorly controlled at last follow-up (>21 mmHg) after treatment of endophthalmitis.

CONCLUSIONS

Streptococcus species and Staphylococcus species were the most common causative organisms in the current series of patients with delayed-onset bleb-associated endophthalmitis. Despite successful treatment of the infection, visual outcomes are generally poor.