Outcomes of Klebsiella endogenous endophthalmitis treated with initial systemic and intravitreal therapy: a 10-year retrospective cohort study.

Background: Management of endogenous endophthalmitis (EE) is challenging. Klebsiella EE, in particular, carries a guarded prognosis and poor visual outcome. We aimed to test the hypothesis that a certain group of Klebsiella EE would carry a better prognosis when presenting with specific signs, compared to the worse-performing group when treated with initial systemic and intravitreal therapy.

Methods: A retrospective cohort study was conducted across two local tertiary hospitals to review all cases of Klebsiella EE from January 2013 to December 2022. Anatomical success was defined by retention of the globe, without intractable retinal detachment or phthisis bulbi. Functional success was defined as achieving a visual acuity of better than 1.3 logMAR.

Results: A total of 56 proven cases of EE were identified. 31 subjects (55.4%) had Klebsiella EE. Of those, 31 eyes of 21 subjects met the inclusion criteria. 4 subjects were unconscious or cognitively impaired at initial presentation. The factors that predict a higher chance of successful treatment with systemic antibiotics and intravitreal antibiotics only, in the Klebsiella EE group, were a better visual acuity at presentation, lack of conjunctival injection, absence of corneal edema, hypopyon, panophthalmitis, and the presence of a fundal view (p < 0.02). The probability of overall treatment success was greater than 50% if the initial visual acuity was better than or close to finger counting at one meter (p = 0.006).

Conclusion: Universal screening of patients with Klebsiella infection and the identification of earlier EE presentation with these prognostic factors that predict a positive or less severe outcome are crucial for the prompt initiation of treatment within this narrow therapeutic window.