Bacterial Infection in the Conjunctiva of Patients with Adenoviral Conjunctivitis

Purpose: We evaluate the microbiological features of mixed infection in adenovirus-infected conjunctiva.Subjects: Isolation of bacteria was performed in 82 samples of adenoviral conjunctivitis at six eye clinics in Japan.Methods: For microbiological diagnosis, we performed immunochromatography (IC) and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis for detection and serotyping of adenovirus, and PCR for detection of herpes simplex virus (HSV) and Chlamydia trachomatis antigens out of 82 samples with adenoviral conjunctivitis.Results: Pathogenic bacteria were isolated in 6 samples out of 82. Out of these 6 cases, 5 samples were gram-negative rods and most of them were Flavobacterium meningosepticum (4 samples). Adenovirus type 8 was isolated from all these mixed infection cases. However, HSV-1 and Chlamydia trachomatis were not found.Conclusions: From these results, it is suggested that gram-negative rods, especially F. meningosepticum, are the most common bacteria causing mixed bacterial infection in adenoviral conjunctivitis.