PERSISTENT ENDOPHTHALMITIS AFTER INTRAVITREAL ANTIMICROBIAL THERAPY

Purpose: To assess the frequency of persistent infection after injecti on of intravitreal antimicrobials as therapy for endophthalmitis and t o determine if persistent infection influences the final visual outcom e after treatment. Methods: In a series of 42 eyes with culture-positi ve endophthalmitis of various types, the authors performed a second vi treous culture and injection of antimicrobial agents in 22 eyes. Repea t cultures were obtained 3 to 8 days after initial therapy in 20 of th e 22 eyes. Results: Twelve of the 22 eyes were persistently culture-po sitive. Organisms identified in the persistently culture-positive eyes included staphylococcal species (n = 4), Streptococcus (n = 4), Serra tia (n = 1), Propionibacterium acnes (n = 1), and fungi (n = 2). Eyes in which the initial antimicrobial therapy failed to eradicate a bacte rial infection had a worse outcome than those that were culture-negati ve on repeat sampling. Final visual acuity of 20/200 or better after r epeat injection was attained in 4 of the 12 culture-positive eyes. Con clusion: A single injection of intravitreal antimicrobial agents may b e insufficient to cure some cases of endophthalmitis, and a second inj ection should be considered in some circumstances.