Povidone-iodine prevents growth of endophthalmitis bacterial isolates after cataract surgery

Administering 5% povidone-iodine for 15 minutes or 10% povidone-iodine for 5 minutes can contribute towards the prevention of the growth of endophthalmitis bacterial isolates, asserts a study in the Journal of Cataract and Refractive Surgery.

Dr Hamid Hosseini et al., Poostchi Ophthalmology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran, performed an experimental study on 44 patients with postoperative endophthalmitis. Ocular-fluid samples were taken from all patients and evaluated by a microbiology laboratory. One millilitre of 1%, 2%, 5%, and 10% povidone-iodine solutions was combined with one millilitre of microbial isolate suspension. Each solution was transferred to appropriate culture media after 1 minute, 5 minutes and 15 minutes of exposure at 37°C.

Of the patients included in the study, organisms were isolated in 30. In 14 patients coagulase-negative Staphylococcus was identified, Streptococcus species in 8 patients, Staphylococcus aureus in 5 patients, Bacillus cereus in 2 patients and Pseudomonas aeruginosa in 1 patient.

The most effective concentration of solution was 5% povidone-iodine for 15 minutes and 10% povidone-iodine for 5 minutes. After long exposure with 10% povidone-iodine 13% of bacterial isolates remained.

The study advises the use of high concentrations of povidone-iodine with a long exposure time for the isolation of endophthalmitis bacteria post-cataract surgery.