Streptococcus pneumoniae keratitis: epidemiology and outcomes over 6 years in a French eye care center.

Purpose: We evaluated the epidemiology, clinical features, microbiology, management and visual outcome of Streptococcus pneumoniae keratitis.

Methods: We retrospectively reviewed the medical charts of patients diagnosed with culture-proven Streptococcus pneumoniae keratitis in a French tertiary center between January 2015 and December 2020.

Results: We analyzed data from 51 eyes of 51 patients with Streptococcus pneumoniae keratitis followed for 64 (19-105) days, out of a total of 1222 eyes with documented bacterial keratitis (4.17%). Most cases (55%) occurred in winter or spring (p = 0.037). A local or systemic risk factor was identified in 39 (76%) and 32 (63%) eyes respectively: previous ocular surgery (55%) followed by glaucoma (24%), and diabetes (18%). Forty-one patients (80%) with severe keratitis remained in hospital for 7 (1-60) days. Polymicrobial infection was detected in 6 eyes (12%) and multidrug resistant strain in 9 eyes (18%). Medical treatment lasted 36 (21-60) days. Adjuvant surgery was required in 13 eyes (25%) mainly for delayed ulcer healing (n = 10), with amniotic membrane transplantation (n = 12) or tectonic keratoplasty (n = 1). In multivariate analysis, endothelial plaque (OR 65.87, p = 0.028), hypopyon (OR 17.8, p = 0.040), and infiltrate > 5mm² (OR 2.49, p = 0.012) were significantly associated with the need for adjuvant surgery. Baseline visual acuity (VA) 2.00(1.33-2.00) logMAR did not improve significantly at final visit (p = 0.121). Eyes requiring adjuvant surgery had worse final VA (p = 0.009).

Conclusion: Streptococcus pneumoniae keratitis are rare in France but may be sight-threatening. Overall VA is poor, most of patients require hospitalization, and some local factors at presentation predict the need for adjuvant surgery.