Sir,
We would like to thank the reviewers for their interest in our publication.[1] Investigators in our department along with our collaborators conducted a randomized trial comparing the various concentrations of topical chlorhexidine (0.05%, 0.1%, and 0.2%) with 5% natamycin for fungal keratitis at our institution in 1997 and concluded that, the nonsevere fungal ulcers with no prior antifungal treatment, when treated with 0.2% chlorhexidine had a favorable outcome at 5 days from the initiation of the treatment compared to 5% natamycin.[2] However, comparison of the long-term outcome of nonsevere fungal ulcers was not statistically significant among the four groups. There was no difference in the outcomes of severe fungal ulcers. The study was limited by small sample size with 8 ulcers in chlorhexidine 0.2% group compared to 16 ulcers in natamycin group. Chlorhexidine is a nonspecific antiseptic which is not commercially available in our region and has to be formulated under strict aseptic precautions. The shelf life of chlorhexidine is <2 weeks. Hence, in our clinical practice, we reserve chlorhexidine 0.2% for corneal ulcers caused by acanthamoeba and we do not use it in fungal keratitis.
Mycotic ulcer treatment trial 2 (MUTT 2) evaluated the efficacy of oral voriconazole as an adjunct to topical antifungals in severe fungal keratitis[3] and concluded that oral voriconazole does not give added benefit in such a scenario. In this trial, topical natamycin was added to topical voriconazole in both the arms after analyzing the results of MUTT 1, which concluded that topical voriconazole should not be used as a monotherapy.[4] This addition of topical natamycin happened after the enrollment of 39 patients of the total sample size of 240 patients. The less number of patients receiving only topical voriconazole precludes any meaningful comparison to establish the superiority of using both natamycin and voriconazole. However, in our clinical practice, we do add topical voriconazole to topical natamycin in large, recalcitrant, and deep ulcers.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
References
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