Mycotic keratitis: Susceptibility to antiseptic agents

Abstract

Oculomycosis is a severe problem in most developing countries. Specific antifungal agents are often unavailable, and are expensive. The use of antiseptic agents was therefore explored. Fungal isolates from patients in India and Ghana were tested against chlorhexidine, povidone iodine, propamidine, and polyhexamethylenebiguanide, and compared with econazole by placing the drugs in wells made in Sabouraud's agar plates seeded with the test organism. Fungal sensitivity testing is a contentious area but this method is simple and cheap. Chlorhexidine showed a good dose related response, povidone iodine showed a good response at all concentrations and econazole was the most effective in vitro. A small pilot study was conducted in India to assess clinical efficacy for fungal corneal ulcers. Both chlorhexidine and econazole proved effective but povidone iodine was ineffective. We suggest that chlorhexidine may be a useful first line agent for fungal keratitis when other antifungals are not available.

Fungal and Parasitic Infections of the Eye

“…Collagen shields impregnated with antimicrobials appear to be a promising approach, and such shields soaked in amphotericin B and replaced daily have been used with success with Aspergillus keratitis (176). The topical use of the antiseptic agent chlorhexidine gluconate at a 0.2% concentration showed efficacy in vitro (169) and in patients with fungal keratitis (209).…”

Effect of topical povidone-iodine versus topical ofloxacin on experimental Staphylococcus keratitis

“…Anecdotal reports showed it to be clinically effective in the treatment of corneal ulcers [6,8]. No effect on mycotic keratitis was noted by Martin et al in a pilot human study [11]. Sharma reported greater subjective improvement with 0.1% PI than with 0.3% gentamicin in experimental staphylococcal keratitis [17].…”

Effect of topical 0.5% povidone-iodine compared to 5% natamycin in fungal keratitis caused by Fusarium solani in a rabbit model: a pilot study

“…Its efficacy against Fusarium solani has been demonstrated in vitro by Martin et al (2) , as well as in vivo (12) . White et al (12) reported that 1% povidone-iodine led to a significant reduction in the duration of experimentally induced disease with Aspergillus niger, in rabbits, without notable irritation.…”

“…Its incidence is variable, but it is clearly higher in regions with a warm, humid climate and/or in an agricultural economy (1) . Studies from different continents identified fungi in 6% to 53% of cases of suppurative keratitis (2)(3) . Filamentous fungi are responsible for the majority of these cases (4) .…”

“…Several studies have demonstrated its effectiveness against bacteria (11) . It is also effective against viruses and fungi (2) . We sought to evaluate the potential clinical efficacy of topical 0.5% povidone-iodine eyedrop preparation by comparing it with a standard therapeutic regimen with topical 5% natamycin for Fusarium solani fungal keratitis in a rabbit model.…”