Results of a trial of combined propamidine isethionate and neomycin therapy for Acanthamoeba keratitis

Purpose: To characterize patients with Acanthamoeba keratitis and to evalua te the safety and efficacy of propamidine isethionate 0.1% ophthalmic solut ion (Brolene) when administered concomitantly with neomycin-polymyxin B-gra micidin ophthalmic solution (Neotricin) in the treatment of Acanthamoeba ke ratitis. Design: Prospective, noncomparative case series. Methods: The authors report the clinical characteristics and outcomes of pa tients who entered this multicentered, open-label, clinical trial. Eighty-t hree patients with Acanthamoeba keratitis representing 87 infected eyes ent ered the trial. Results: Sixty (69%) of the 87 eyes enrolled had data analyzed for treatmen t efficacy and safety. Of these 60 eyes, 50 (83%) experienced treatment suc cess. Thirty (60%) patients successfully treated adhered to treatment proto col guidelines. Patients who broke protocol had disease exacerbation during the maintenance therapy phase. The only eyes lost/enucleated were 7 of 17 in which penetrating keratoplasty was performed before eradication of the i nfectious agent. Conclusion: Propamidine isethionate and neomycin are an effective treatment for Acanthamoeba keratitis, Penetrating keratoplasty should be performed o nly for visual rehabilitation and not to "debulk" an active infection. The authors advocate treating patients with topical medications, mainly Brolene , until all organisms are eradicated. There should be no signs of infection for at least 3 months in the patients not receiving antiamebic medications before penetrating keratoplasty is performed.