[Etiological characteristics, clinical manifestations, and prognosis of patients with endogenous endophthalmitis in 2024: a single-center retrospective cohort study].

Objective: To investigate the etiological characteristics, clinical manifestations, and prognosis of patients with endogenous endophthalmitis (EE). Methods: This was a retrospective case series study. Clinical data from patients diagnosed with EE and treated at Henan Eye Hospital between January 2024 and December 2024 were collected. Preoperative examinations included best-corrected visual acuity, intraocular pressure, and ocular B-ultrasound. The ocular status was evaluated using a slit-lamp biomicroscope and indirect ophthalmoscope. Samples of the aqueous humor and vitreous body were obtained for pathogenic bacterial culture or next-generation sequencing. Patients with previous etiological test results of blood or body fluids were included in the analysis. All patients received systemic antibiotic or antifungal treatment. Depending on disease severity, patients underwent intravitreal injection, pars plana vitrectomy (PPV), or evisceration with artificial eye socket implantation. Etiological characteristics, clinical manifestations, and treatment outcomes were assessed. Statistical analyses were performed using the Fisher's exact test or Monte Carlo exact method. The logistic regression analysis was applied to identify factors influencing the visual acuity improvement by calculating the odds ratio (OR) and its 95% confidence interval (95%CI). Results: A total of 38 eyes of 33 patients, 19 (57.6%) males and 14 (42.4%) females, diagnosed with EE were included. There were 16 cases (48.5%) in the right eye, 12 cases (36.4%) in the left eye, and 5 cases (15.1%) in both eyes. The age ranged from 22 to 80 years old, with a mean age of (59.5±13.0) years. Among the 38 affected eyes, 23 eyes (60.5%) had bacterial infections, including 13 eyes (34.2%) with Klebsiella pneumoniae, 5 eyes (13.2%) with Staphylococcus aureus, 2 eyes (5.3%) with Escherichia coli, 1 eye (2.6%) with Nocardia species, 1 eye (2.6%) with coinfection of Listeria monocytogenes and Enterobacter cloacae complex, and 1 eye (2.6%) with no available etiological test results. Thirteen eyes (34.2%) had fungal infections, including 5 eyes (13.2%) with Candida albicans, 2 eyes (5.3%) with Candida parapsilosis, 2 eyes (5.3%) with Aspergillus fumigatus, 1 eye (2.6%) with Fusarium species, 1 eye (2.6%) with Aspergillus flavus, 1 eye (2.6%) with Chaetomium globosum, and 1 eye (2.6%) with negative etiological test results in the vitreous humor. Two eyes (5.3%) had mixed fungal and bacterial infections. In all patients, ocular B-mode ultrasonography revealed severe vitreous opacity. Three eyes (7.9%) underwent evisceration combined with orbital implant placement. Treatment was discontinued for 2 eyes (5.3%) due to severe systemic conditions in the respective patients. The remaining 33 eyes (86.8%) were included in the visual acuity analysis at the last follow-up, of which 22 (66.7%) showed improved visual acuity, 4 (12.1%) had decreased visual acuity, and 7 (21.2%) had stable visual acuity. The logistic regression analysis revealed that PPV improved the final visual acuity (OR=0.068, 95%CI: 0.014-0.337, P=0.004). Conclusions: The single-center data from 2024 indicated that bacteria were the predominant pathogenic organisms of EE, followed by fungal species. Patients with EE exhibited severe vitreous opacity, and PPV played a crucial role in the visual prognosis.