Microbiological study of infectious endophthalmitis with positive culture within a 13 year-period

Our objectives are to describe the microbial spectrum and antimicrobial susceptibility of isolates from patients with culture-proven endophthalmitis. Retrospective study of patients with microbiological diagnosis of endophthalmitis treated at the Ophthalmology Department of the General Hospital La Mancha Centro in the period 1996-2008. The identification of isolates was performed using the automated VITEK-2® and Api galleries (bioMérieux, Spain SA). The antimicrobial susceptibility was performed by the VITEK-2® system (bioMérieux, Spain SA), E-test strips (MIC Test Strip, Liofilchem, Italy) and Sensititre® YeastOne trading system (Trek Diagnostic Systems, Ohio, USA) for Candida species. Forty four (70%) of 63 cases of endophthalmitis were culture positive. Gram-positive bacteria were much more common than gram-negative bacteria in both postoperative endophthalmitis (POE) and post-traumatic endophthalmitis (PTE). Staphylococcus epidermidis was predominant in POE, while Bacillus sp. predominated in the PTE; furthermore, the 75% of total fungal isolates corresponded to postraumatic cases. The isolated strains showed 100% susceptibility to vancomycin, ceftazidime and amikacin, while resistance to ciprofloxacin was greater than 15%. The empirical antifungal therapy failed in 50% of cases. The visual prognosis was significantly less favorable in the PTE. Based on the susceptibility of our isolates, vancomycin, ceftazidime and amikacin are good choices for empirical treatment of endophthalmitis, unlike ciprofloxacin. We recommend conducting antifungal prophylaxis after penetrating ocular trauma in a rural environment.