This article is part of MPR’s coverage of the American Academy of Ophthalmology 2019 Meeting, taking place in San Francisco, CA. Our staff will report on medical research related to eye disorders, conducted by experts in the field. Check back regularly for more news from AAO 2019.

SAN FRANCISCO – For patients with progressive Acanthamoeba keratitis, oral miltefosine may be an effective adjunct treatment for preventing recurrence, according to retrospective case series presented at the 2019 American Academy of Ophthalmology Meeting in San Francisco, CA.

Acanthamoeba keratitis is a rare protozoal infection of the cornea that could potentially lead to visual impairment and blindness. Early diagnosis is crucial as the infection can be difficult to treat due to the resilient double-walled cyst form of Acanthamoeba. Treatment often includes a topical cationic antiseptic agent (polyhexamethylene biguanide [0.02%] or chlorhexidine [0.02%] with or without a diamidine), as well as topical cycloplegic solutions and oral nonsteroidal antiinflammatory drugs for pain control.

The use of oral miltefosine, an antileishmanial agent, was evaluated in 5 patients (all contact lens users) diagnosed with progressive Acanthamoeba keratitis between January 2017 and January 2019. While 3 patients had worsening symptoms following treatment initiation, 2 had significant improvement after 1 week of treatment with miltefosine. “Optical penetrating keratoplasty was successfully performed 3 to 6 months after clinical resolution. Cultures were negative for all corneal buttons,” the study authors reported. 

At follow-up, all grafts remained clear with no signs of infection recurrence or graft rejection. Based on these results, the study authors concluded that “oral [miltefosine] may be a viable adjunctive therapy for recalcitrant [Acanthamoeba keratitis], however, its use may be associated with a severe inflammatory reaction.” They added that “a short course of topical or possibly systemic corticosteroids during [miltefosine] induction may reduce inflammation and destruction of surrounding tissue in such cases.”

Reference

Naranjo, A, et al. Systemic Miltefosine as an Adjunct Treatment of Progressive Acanthamoeba Keratitis. Poster number: PO116. The American Academy of Ophthalmology Meeting; October 12-15 2019.