ACANTHAMOEBA KERATITIS: 14 CASES TREATED WITH POLIHEXANIDE 0.08% IN MONOTHERAPY

To report efficacy and safety topical PHMB (polihexanide) 0.08% (0.8 mg/ml) in monotherapy for Acanthamoeba Keratitis (AK) treatment.

The study was done at Hospital La Fe, Valencia (Spain)

We report 14 cases with AK. Principal inclusion criteria were 12 years of age or older, clinical findings consistent with AK and positive Acanthamoeba PCR. Principal exclusion criteria were concurrent herpes or fungal keratitis and use of antiamebic and antifungal therapy. During 6 months in every case, we treated all the patients with this regimen (daily time only): 1 drop every hour (day 1 to 5), 1 drop every 2 hours (day 6 to 12), 1 drop every 3 hours (day 13 to 20), 1 drop every 4 hours (day 21 to resolution). The medical cure was defined   as complete clinical resolution visualized by slit lamp and absence of corneal inflammation. The main outcome measure was clinical findings within 6 months, and secondary outcomes including best corrected visual acuity. Safety outcomes included adverse event rates. 

Fourteen eyes of AK with variable severity received PHMB 0.08% at the described regimen (Stage 1=3, Stage 2= 3, Stage 3=1, Stage 4=4, Stage 5=3) . Ten eyes were contact lens wearers. The medical cure rate within 6 months was 100% with complete resolution in 14 cases. The median time of treatment was 122 days.  Secondary outcomes were median best-corrected visual acuity of 20/20. 2 of 10 patients required Optic Penetrating Keratoplasty due to the severity of the infectious process and the central leucoma. No drug-related adverse events occurred. 

PHMB 0.08% monotherapy may be effective for Acanthamoeba keratitis with medical cure rates of more than 85%