Endphthalmitis after cataract surgery in Sweden 2018–2024: associations with preoperative visual acuity and intracameral antibiotic regimens

Background/aims Cataract surgery is one of the world’s most common and successful procedures. Postoperative endophthalmitis (PE) is rare but may be devastating. This study investigated associations between preoperative visual acuity (VA), other patient-related and surgery-related characteristics and PE. As a secondary objective, outcomes associated with the most commonly used intracameral antibiotic regimens were explored. Methods This retrospective cohort study used data from the population-based Swedish National Cataract Register from 2018 to 2024. Results Among 979 534 procedures, PE incidence was 0.013% (131 cases). In a multivariate analysis, male sex, ocular comorbidity and capsule complication showed higher ORs for PE while preoperative VA≥20/40 and immediate sequential bilateral surgery showed lower ORs for PE. Patients with better preoperative VA were younger and had fewer ocular comorbidities, intraoperative challenges and complications, indicating a more favourable case mix. Endophthalmitis rates varied by intracameral antibiotic regimen: 0.017% with cefuroxime alone, 0.011% with cefuroxime plus ampicillin and 0.010% with moxifloxacin. No regimen demonstrated statistically significant superiority. Enterococci occurred more frequently with cefuroxime. Time to PE diagnosis was longer with combination therapy and moxifloxacin versus cefuroxime alone. Visual outcomes were generally poor (48%<20/200), but moxifloxacin cases achieved≥20/40 final VA more often than cefuroxime (50% vs 23%). Conclusions PE incidence was very low. Better preoperative VA and immediate sequential bilateral cataract surgery were associated with lower observed odds, probably reflecting favourable case mix and residual confounding rather than causal protection. No IC antibiotic regimen was independently associated with lower PE incidence.