Purpose
To identify the clinical features, organisms, treatment modalities and outcomes of patients with endophthalmitis associated with glaucoma drainage implant (GDIs).
Methods
A non-comparative consecutive case series of patients at the Bascom Palmer Eye Institute diagnosed with culture positive endopthtalmitis associated with GDIs between January 1, 1999 and November 1st 2014 was performed.
Results
A total of 13 patients (9 female and 4 male) were identified. Average age was 71 years (range 55-92). Thirteen eyes were included (8 right and 5 left), two of which had two tubes. All GDIs were Baerveldt glaucoma devices, 10 were 101-350, 2 were 101-250 and 3 were unknown. The average time elapsed from GDI surgery to endophthalmitis was 16 months (range 3 days to 52 months). Eight eyes had conjunctival breakdown with the tube being exposed in 4 eyes, the plate in 1 and scleral patch exposure in 3 eyes. The remaining 4 eyes had a history of either tube placement or revision within four months prior to diagnosis. The most common organism was Staphylococcus epidermidis that grew from 5 eyes (Table 1). Mycobacterium was isolated from two eyes. Multiple organisms were isolated from two eyes. Eleven eyes received intravitreal antibiotics, one eye with no light perception vision was eviscerated as primary treatment and one eye where mycobacterium was cultured from the tube was treated with oral and topical antibiotics. GDIs were not removed in 4 eyes that were successfully treated. Six eyes underwent removal of the GDI and evisceration or enucleation was required in 3 cases. Median pre-infection visual acuity (VA) was 20/80, (range 20/30 to HM). Two patients returned to baseline or better than baseline vision. Six patients had NLP vision, one patient had LP vision and one had HM vision. Of the remaining 5 patients three had vision better than 20/200. Average follow up was 42 months (range 3-96 months).
Conclusions
A percentage of cases (9/13) are associated with conjunctival breakdown while others associated with a recent surgical procedure. Infections were caused by a broad spectrum of microbes, including mycobacteria with Staphylococcus epidermidis being the most common isolate (5/13). The remaining isolates were predominantely gram-positive organisms.