Causative Microorganisms of Infectious Endophthalmitis: A 5-Year Retrospective Study

This study aimed to identify the microbial etiology of infectious endophthalmitis and to determine the antibacterial susceptibilities of bacterial isolates at an eye hospital in South China. A retrospective analysis was carried out on 330 patients with clinically diagnosed infectious endophthalmitis who underwent microbiological evaluation from January 2010 to December 2014. Of the 330 patients, 193 patients (58.5%) had posttraumatic endophthalmitis, 67 patients (20.3%) had postoperative endophthalmitis, 61 patients (18.5%) had endogenous endophthalmitis, and 9 patients (2.7%) had postcorneal infective endophthalmitis. Of the 105 cases (31.8%) of culture-positive endophthalmitis, 79 cases (75.2%) had bacterial growth and 26 cases (24.8%) had fungal growth. In posttraumatic endophthalmitis, Gram-positive bacteria were the predominant species, followed by Gram-negative bacteria and fungi. In endogenous endophthalmitis, Gram-negative bacteria were the predominant species, followed by fungi and Gram-positive bacteria. In postsurgical endophthalmitis, all infections were bacterial. However, in postcorneal infective endophthalmitis, all infections were fungal. Overall, levofloxacin showed the highest activity against bacterial isolates. There was a significant difference in the susceptibility to tobramycin between the isolates from posttraumatic and postoperative endophthalmitis (p < 0.05). The results of this study identify the microbial spectrum of infectious endophthalmitis in this clinical setting.