Intrastromal antifungal injection as a successful modality of treatment for fungal keratitis: a case series

Abstract

Fungal keratitis is a dreaded occurrence in the cornea and anterior segment given the difficulty in treating the disease. Hereby reporting 5 cases of fungal keratitis causes by virulent organisms such as Aspergillus versicolor, Aspergillus fumigatus, Phialophora sp, and Fusarium sp. A retrospective interventional case series of 5 fungal keratitis which were successfully treated by intrastromal antifungal injection performed by a single surgeon from March 2017 till April 2018. The fungal keratitis stromal abscess sizes range from largest of 3mm x 2mm to smallest of 1mmx 1mm, mostly located paracentral and one case was noted to have hypopyon measuring about 1mm. On the first week of treatment, patients noted to exhibit poor response to topical antifungal. Hence, intrastromal amphotericin B injection 5mcg/0.1ml about 0.1ml administered into the affected eye ranging from once to 3 times in all patients except for one patient; who is post-operative 1 year penetrating keratoplasty infected with Phialophora keratitis is given intrastromal amphotericin B injection 5mcg/0.1ml about 0.1ml for 3 times and intrastromal voriconazole injection 50mcg/0.1ml about 0.1ml for 3 times. Within next four weeks, all the 5 cases of fungal keratitis became completely quiet with healed epithelial defect and corneal scarring. In summary, the intrastromal antifungal injection can constitute a good modality for the treatment of recalcitrant cases of fungal keratitis, revealing highly potent antifungal effects as the medication is administrated directly to the site of keratitis, promises shorter recovery period, and early intrastromal antifungal injection also leads to quicker healing with good vision prognosis.

Challenging case of treating fungal keratitis

“…Another study showed improvement in 14 out of 20 patients, which required 2.65 injections on average [14]. It is important to mention that no adverse effects of intrastromal voriconazole application in a form of corneal haze, edema, erosions, and toxicity, which was consistent with cases from other studies [8].…”

“…The limitation of topical antifungal medications is their poor penetration due to their high molecular size and toxicity [7] that leads to suboptimal results of the treatment. Many studies proved the efficacy of combined topical and systemic antifungal medications in the early stages of keratitis [8]. This led to the need of finding alternative methods of reaching the fungi with the intracameral and intrastromal application.…”

“…Many studies report that it is usually required to repeat intrastromal injections at least two to three times for the treatment to be effective [13]. Maniam et al also reported an improvement after two to three injections [8]. Kalaiselvi et al reported the improvement in 72% of patients treated with more than one injection of intrastromal voriconazole that was previously treated and did not respond to topical medication [10].…”

Intrastromal Antibiotic Injection in Polymicrobial Keratitis: Case Report and Literature Review

“…Further complicating its management, significant antimicrobial resistance is often identified among one or more of the causative organisms [ 2 ]. While intrastromal injection of antimicrobial agents has garnered increased attention in the treatment of fungal keratitis refractory to topical therapy [ 4 , 5 , 6 , 7 ], the utility of this approach is still uncertain [ 8 , 9 ], and intrastromal antibiotic injection to treat bacterial keratitis is even less well established. To the best knowledge of the authors, examples of successful treatment of bacterial keratitis with intrastromal antibiotic injection in the literature are limited to a handful of case reports [ 10 , 11 , 12 , 13 , 14 ].…”