Efficacy of intravitreal povidone-iodine administration for the treatment of Candida albicans endophthalmitis in rabbits

This study aimed to investigate the efficacy of intravitreal povidone-iodine (PI) administration for the treatment of Candida albicans endophthalmitis. Forty New Zealand white rabbits were divided into four groups (n = 10 per group). After the induction of endophthalmitis using Candida albicans, groups A, B, and C received single intravitreal injections of 0.035 mg voriconazole, 0.3 mg PI, and their combination, respectively. Rabbits that were administered sham injections were in group D as controls. Fundus photography, vitreous culture, electroretinography (ERG), and histologic examinations of the retina were conducted on day 7. The anterior chamber flare (grade 0 to 4), severity of iritis (grade 0 to 4), and vitreous opacity (grade 0 to 3) were scored. Candida albicans was cultured in the vitreous sample. On day 7, the vitreous opacities were found in all groups. Compared to that in group D, groups A, B, and C showed a lower score for flare (p < 0.001) and iritis (p < 0.001) and less fungal growth in the vitreous culture (n = 2, 1, 1, and 10 in groups A, B, C, and D, respectively; p < 0.001). Furthermore, ERG and histologic findings demonstrated less affected a- and b-waves and damaged retinal tissues in groups A, B, and C. However, these findings were not different among groups A, B, and C. PI significantly improved Candida albicans endophthalmitis, and the effect was comparable that of the voriconazole, although some vitreous opacities remained. No synergistic effect of the combination of PI and voriconazole was observed. Intravitreal PI may be useful to treat Candida albicans endophthalmitis.

Automated summary

Intravitreal administration of povidone-iodine demonstrated efficacy in treating Candida albicans endophthalmitis by reducing inflammation and fungal growth. However, the combination with voriconazole did not show a synergistic effect. The findings suggest that povidone-iodine may be a useful treatment option for this condition.