Abstract
Abstract: :
Purpose: To investigate causes,treatment modalities, and visual outcomes in cases of Streptococcus Pneumoniae, and to determine organism sensitivities and resistance patterns to various antibiotics. Methods: All intraocular culture positive cases of S. pneumoniae endophthalmitis from 1987-2000 were identified by the Microbiology department at the Bascom Palmer Eye Institue. Sensitivity of the organisms to each of several antibiotics was determined, as was the minimum inhibitory concentration for these antibiotics to each organism. Clinical charts were then reviewed and the causes of endophthtlmitis, baseline,presenting, and final visual acuities, and treatments were noted for each patient. Results: 22 patients were identified. Underlying etiology included post-penetrating keratoplasty (PK) (8/22,36%); post-glaucoma surgery (4/22,18%); post-cataract surgery (3/22,14%); post-traumatic (3/22,14%); corneal ulcer (2/22,9%); and endogenous (2/22,9%). 13/21 (62%) patients had LP or NLP presenting visual acuity. Mean final visual acuity (mean follow up: 8 months) was 8/200. 9/10 (90%) eyes with presenting LP or NLP vision underwent Pars Plana Vitrectomy (PPV) with injection of intraocular antibiotics (IOAB). Other treatments included: vitreous tap and injection of antibiotics (T&I) (three patients), T&I with secondary PPV (six patients), PK with IOAB (one patient), and evisceration (two patients). 50% of the organisms were resistant to Gentamycin with decreasing resistance to Penicillin (18%), Ofloxacin (14%), Oxacillin (9%), Ciprofloxacin (9%), and TMP/SMX (9%). No organisms were resistant to Vancomycin, and all patients received intraocular Vancomycin. Three cases had favorable outcomes. One case had a post-PK suture abscess and had aqueous positive but vitreous negative cultures for S. pneumoniae. Two cases had penetrating trauma and intraocular foreign bodies (IOFB). Vitreous cultures were later positive for S. pneumoniae. Mean final visual acuity in these three patients was 20/30. Conclusion: Streptococcus pneumoniae endophthalmitis was most commontly encountered as a post-surgical complication (82%), with suture abscess post-PK as the most common etiology. S. pneumoniae is often resistant to Gentamycin, Penicillin, and fluoroquinolones but was uniformly sensitive to Vancomycin in the current study. Final visual outcomes are ususally poor despite adequate antibiotic coverage, but favorable outcomes may be seen in eyes with limited endophthalmitis or in eyes with trauma and immediate Pars Plana Vitrectomy/intraocular antibiotics.
Keywords: 398 endophthalmitis • 328 bacterial disease • 468 microbial pathogenesis: clinical studies