Two-Decade Retrospective Analysis of Postoperative Endophthalmitis at a Tertiary Care Academic Center: Microbial Spectrum, Treatment Modalities, and Visual Outcomes

Abstract

Purpose: To determine the causative microorganisms, treatment modalities, visual outcomes, and factors influencing the results of postoperative endophthalmitis at a major tertiary referral eye care facility in Thailand. Patients and Methods: A retrospective review was conducted on patients diagnosed with postoperative endophthalmitis over a 20-year period. The collected data included demographic characteristics, endophthalmitis classification, causative organisms, treatment modalities, and final visual acuity. Factors associated with improved visual outcomes were explored. Results: This study included 163 eyes (163 patients). Eighty-seven cases (53.4%) were acute-onset, while the rest were delayed-onset. Cataract surgery was the most common prior intraocular procedure. Microorganisms were identified by culture in 29.4% of cases. Coagulase-negative Staphylococcus species were predominant among acute-onset cases (57.7%), followed by Enterococcus faecalis (15.4%); coagulase-negative Staphylococcus species also were predominant among delayed-onset cases (18.9%). The most common treatment was immediate pars plana vitrectomy (PPV) with intravitreal injection. Significant improvements in visual acuity (VA) were observed in the immediate and delayed PPV groups, with mean improvements of 0.80 logMAR (p < 0.001) and 0.87 logMAR (p = 0.001), respectively. Globe salvage was achieved in 96.3% of cases, with a median final VA of 20/200. Visual improvement, stability, and deterioration were observed in 61.2%, 11.5%, and 27.4% of cases, respectively. Factors associated with poor visual outcomes were diabetes mellitus (p=0.019), visual acuity at initial presentation of 20/200 or worse (p<0.001), and delayed-onset postoperative endophthalmitis (p=0.001). Conclusion: Immediate PPV with intravitreal injection remains the most common and effective treatment for postoperative endophthalmitis, achieving significant visual acuity improvement and high rates of globe salvage. Visual outcomes were significantly influenced by diabetes mellitus, poor visual acuity at initial presentation, and delayed-onset endophthalmitis, underscoring the importance of timely and tailored management strategies.