Postoperative Endophthalmitis Caused by Cutibacterium (Formerly Propionibacterium ) Acnes: Case Series and Review

We report the clinical features, treatment strategies and outcomes in a series of patients with infectious endophthalmitis after cataract surgery caused by Cutibacterium acnes (C. acnes) , formerly known as Propionibacterium acnes (P. acnes) . This retrospective case series includes six eyes of six patients with chronic postoperative endophthalmitis caused by culture-proven C. acnes from December 2010 to July 2019 at a University referral center. All patients underwent prior cataract extraction with intraocular lens (CE/IOL) implantation. The mean time between cataract surgery and the microbiologic diagnosis of endophthalmitis was 7.4 ± 5.2 months (range 1.5–17 months). The average time from obtaining the specimen to culture positivity was 7.7 ± 4.4 days (range 3–15 days). Three eyes (50%) presented with hypopyon and three eyes (50%) presented with prominent keratic precipitates without hypopyon. Presenting visual acuity ranged from 20/25 to 2/200. Initial treatments included intravitreal antibiotics alone ( n = 2), pars plana vitrectomy (PPV) with partial capsulectomy and intravitreal antibiotics ( n = 3), and pars plana vitrectomy with IOL removal and intravitreal antibiotics ( n = 1). Follow-up treatments included IOL removal ( n = 2), intravitreal antibiotics ( n = 1), and topical antibiotics ( n = 1). The best-corrected visual acuity at last follow-up was 20/70 or better in all patients. In a literature review, the clinical features and treatment outcomes for all case series of delayed-onset postoperative endophthalmitis caused by C. acnes ( n = 120) are listed . A definitive cure (the absence of recurrent inflammation) was achieved in 100% of patients that underwent IOL removal, in 77% of those that underwent PPV/partial capsulectomy and intravitreal antibiotics, and in 18% of cases treated with intravitreal antibiotics alone. Endophthalmitis after CE/IOL caused by C. acnes is characterized by slowly progressive intraocular inflammation and has a protracted course from surgery to microbiologic diagnosis. Visual outcomes are generally favorable, but IOL explantation may be necessary for definitive cure.