Rose Bengal Photodynamic Antimicrobial Therapy Treats Acanthamoeba Keratitis

Rose bengal photodynamic antimicrobial therapy (RB-PDAT) shows promise as an adjuvant treatment for acanthamoeba keratitis (AK), according to a poster presented at the 2023 Southeastern Educational Congress of Optometry (SECO) meeting in Atlanta from March 1 to 5.

Anna Panapakides, OD, and Anat Galor, MD, of the Miami Veterans Affairs Medical Center, reviewed the clinical presentations, diagnostic modalities, and treatment options for AK and presented a case study of a 59-year old man presenting for treatment with signs and symptoms of AK.

AK, which causes about 5% of microbial corneal ulcers and primarily affects contact lens wearers, can mimic other keratitis forms and threaten vision. It can adhere to mannose glycoproteins of the corneal epithelium and secrete proteins that overwhelm the epithelium and stroma, causing severe pain, vision loss, foreign body sensation, photophobia, and unilateral tearing, according to the presenters. 

Presentation may involve ring infiltrate (≅50%), and most individuals present with radial neuritis. Those who fail to obtain treatment may experience stromal and epithelial loss. Treatments include topical therapy, epithelial debridement, miltefosine, therapeutic penetrating keratoplasty, optical penetrating keratoplasty, and RB-PDAT, the poster shows. While the routine treatment course typically begins with topical therapy, adjuvant RB-PDAT has demonstrated success in treating AK and may lessen the burden of topical therapy, according to the presenters.