Pasteurella canis and Granulicatella adiacens conjunctivitis outbreak resistant to empirical treatment in a child welfare agency.

Purpose: To investigate pathogens associated with bacterial conjunctivitis resistant to the empirical treatment and their antibiotic resistance in a child welfare agency.

Methods: Twenty-eight eyes in 14 children with a median age of 3 months with conjunctivitis resistant to the empirical treatment were included in this study. Samples were taken three times from the inferior fornix in both eyes using cotton swabs, cultured onto chocolate and blood agar, and prepared for Gram staining. Antibiograms were evaluated according to the Clinical and Laboratory Standards Institute criteria by disc diffusion method.

Results: The conjunctival culture positivity rate was 35.7% in eyes with conjunctivitis resistant to the empirical treatment. The most common isolated bacteria were Pasteurella canis (25%), penicillin-nonsusceptible Streptococcus pneumoniae (7.1%), and Granulicatella adiacens (3.6%). According to culture results, ophthalmic solutions of vancomycin (50 mg/mL) or gentamicin (30 mg/mL) were applied in eyes with positive conjunctival culture. Previously applied multiple treatments were stopped in eyes with negative conjunctival culture. All eyes improved clinically during follow-up.

Conclusion: Because unusual pathogens may cause a conjunctivitis outbreak, physicians should not insist on empirical treatment. Taking conjunctival culture and antibiotic switching according to antibiogram may be helpful.