Clinical outcomes and prognostic factors associated with acanthamoeba keratitis.
ABSTRACT To describe the clinical characteristics, time of presentation, risk factors, treatment, outcomes, and prognostic factors on a recent series of Acanthamoeba keratitis (AK) treated at our institution.
Retrospective case series of 59 patients diagnosed with AK from January 1, 2004 to December 31, 2008. Of these 59 patients, 51 had complete follow-up data and were analyzed using univariate and multivariate logistic regression analyses performed with "failure" defined as requiring a penetrating keratoplasty (PKP) and/or having (1) best-corrected visual acuity (BCVA) < 20/100 or (2) BCVA < 20/25 at the last follow-up. A single multivariate model incorporating age, sex, steroid use before diagnosis, time to diagnosis, initial visual acuity (VA), stromal involvement, and diagnostic method was performed.
Symptom onset was greatest in the summer and lowest in the winter. With failure defined as requiring PKP and/or final BCVA < 20/100, univariate analysis suggests that age > 50 years, female sex, initial VA < 20/50, stromal involvement, and patients with a confirmed tissue diagnosis had a significant risk for failure; however, none of these variables were significant using multivariate analysis. Univariate analysis, with failure defined as requiring PKP and/or final BCVA < 20/25, showed stromal involvement and initial VA < 20/50 were significant for failure-only initial VA < 20/50 was significant using multivariate analysis.
Symptom onset for AK is greatest in the summer. Patients with confirmed tissue diagnosis and female patients may have a higher risk for failure, but a larger prospective population-based study is required to confirm this. Failure is likely associated with patients who present with stromal involvement and patients presenting with an initial BCVA worse than 20/50.
Article: Amoebic infection of the eye.[show abstract] [hide abstract]
ABSTRACT: A healthy Huntingdonshire schoolteacher of 32 had mild unilateral keratoconjunctivitis and uveitis which did not respond to treatment. 6 months later progressive indolent corneal ulceration, pain, and loss of vision led to a corneal graft, which was rejected. A free-living soil amœba, Acanthamœba polyphaga, was repeatedly isolated from the affected eye. A Lincolnshire farmer of 59 developed an identical clinical condition which required enucleation of the eye after a year. A similar Acanthamœba was grown from his eye tissue. These are the first eye infections caused by free-living amœbæ to be reported in the U.K.The Lancet 01/1975; 2(7896):1537-40. · 39.06 Impact Factor
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ABSTRACT: Acanthamoeba keratitis is a rare, serious protozoal infection of the cornea associated with wearing contact lenses. To identify risk factors in soft contact lens wearers, we interviewed 27 patients with Acanthamoeba keratitis and 81 uninfected matched controls to compare contact lens care practices, brands of contact lenses and associated solutions, and behavioral activities. Patients were significantly more likely than controls to use homemade saline instead of commercially prepared saline (21/27 [78%] vs 14/81 [17%]; odds ratio [OR], infinity), and wear their lenses while swimming (17/27 [63%] vs 24/81 [30%]; OR, 6.2). Contact lens disinfection schedules could be determined for 25 of the patients and all of the controls. Patients were significantly more likely than controls to disinfect their lenses less frequently than recommended by lens manufacturers (18/25 [72%] vs 26/81 [32%]; OR, 5.8). Microbiologic assay of contact lens solutions from controls showed frequent contamination with high levels of bacteria. Acanthamoeba species were isolated from homemade saline solutions from two controls. These findings emphasize adherence to recommended methods of soft contact lens care, especially when using nonsterile lens care solutions.JAMA The Journal of the American Medical Association 08/1987; 258(1):57-60. · 29.98 Impact Factor
- International Ophthalmology Clinics 02/1994; 34(1):19-25.