Acute-onset endophthalmitis caused by Staphylococcus warneri

To report a series of patients with acute-onset bacterial endophthalmitis caused by culture proven Staphylococcus warneri, and to characterize clinical outcomes and microbiologic susceptibilities of this organism.

This study included 8 eyes of 8 patients. The etiologies included intravitreal injection (4), anterior segment surgery (3), and glaucoma surgery (1). All isolates (100 %) of S. warneri demonstrated sensitivity to vancomycin with minimal inhibitory concentration (MIC) values ranging from <0.5 to 1, and to gentamycin with MIC values ranging from <0.5 to 4 mcg/ml. All isolates (100 %) were also sensitive to a beta-lactam with MIC values reported as ≤ 0.25 mcg/ml and to fluroquinolones with MIC values ranging from 0.12 to 0.5 mcg/ml. After initial treatment with intravitreal antibiotics, 6 of 7 (85.7 %) patients subsequently underwent pars plana vitrectomy. Best-corrected visual acuity at last follow-up was ≤5/200 in 5/7 (71.4 %) of patients, and was ≥20/150 in 2/7 (28.6 %) of patients.

Acute-onset endophthalmitis due to Staphylococcus warneri is associated with a range of intraocular procedures. After initial treatment with intravitreal antibiotics, additional treatments are often necessary. Vancomycin, amikacin, and ceftazidime remain consistent options, providing coverage against S. warneri in acute-onset endophthalmitis.