Chlorhexidine gluconate 0.2% as a treatment for recalcitrant fungal keratitis in Uganda: a pilot study

Abstract

ObjectiveFungal keratitis is a major ophthalmic public health problem, particularly in low-income and middle-income countries. The options for treating fungal keratitis are limited. Our study aimed to describe the outcomes of using chlorhexidine 0.2% eye-drops as additional treatment in the management of patients with recalcitrant fungal keratitis.MethodsThis study was nested within a large cohort study of people presenting with microbial keratitis in Uganda. We enrolled patients with recalcitrant fungal keratitis not improving with topical natamycin 5% and commenced chlorhexidine 0.2%. Follow-up was scheduled for 3 months and 1 year. The main outcome measures were healing, visual acuity and scar size at final follow-up.ResultsThirteen patients were followed in this substudy. The patients were aged 27–73 years (median 43 years). Filamentous fungi were identified by microscopy of corneal scrape samples in all cases. Isolated organisms included Aspergillus spp, Fusarium spp, Candida spp, Bipolaris spp and Acremoninum spp. At the final follow-up, nine patients (75%) had healed; three had vision of better than 6/18. Three patients lost their eyes due to infection. In the remaining nine cases, corneal scarring was variable ranging from 4.6 to 9.4 mm (median 6.6 mm, IQR 5.9–8.0 mm); of these five had dense scars, three had moderate scars and one had a mild scar. None of the patients demonstrated signs of chlorhexidine toxicity during the follow-up.ConclusionChlorhexidine 0.2% was found to be a useful sequential adjunctive topical antifungal in cases of fungal keratitis not responding to natamycin 5%, which warrants further evaluation.

Management of Filamentous Fungal Keratitis: A Pragmatic Approach

“…These results suggest natamycin remains the preferred first-line monotherapy treatment for filamentous fungal keratitis, whilst chlorhexidine 0.2% may be considered in situations where natamycin is unavailable. A recent case series from Uganda suggests a potential adjunctive role for chlorhexidine 0.2% in addition to natamycin 5% in recalcitrant cases [ 58 ], with a large randomised controlled trial currently underway to explore this role further [ 59 ].…”

“…Natamycin should be the first-line agent in such a protocol, with chlorhexidine substituted should natamycin not be available ( Figure 5 ). Chlorhexidine may have a role as an adjunctive agent to natamycin [ 58 ], with work currently under way in East Africa to investigate this [ 59 ]. Although large-trial data are lacking, topical amphotericin B could be considered when other agents are unavailable, or as an adjunctive agent in challenging cases.…”

Fusarium Keratitis—Review of Current Treatment Possibilities

“…A pilot study from Uganda, in which CHX was used as a adjunctive therapy in recalcitrant fungal keratitis not responding to monotherapy with 5% NAT, among others, covered three cases of Fusarium spp. keratitis, of which only one was successfully treated [ 104 ]. In one of two other cases that ended up with eviscerations, perforation was found at presentation.…”

Re-estimation of the burden of serious fungal diseases in Uganda

“…Fungal keratitis contributes to over 60% of all cases of microbial keratitis in Uganda. 112 , 113 Treatment remains a challenge, 114 with over 25% of the patients losing their sight or eye, with their overall and ocular quality of life grossly affected. 115 Across Africa, diagnostic procedures for sample collection for pathogen identification remain a major limitation in the diagnosis of fungal keratitis.…”