Abstract
Purpose:
To describe the clinical presentation, management, and outcomes of patients with Acanthamoeba keratitis (AK) in the Bay Area before and after the most recent AK epidemic beginning in 2004-2005.
Methods:
Retrospective review of all patients with culture proven Acanthamoeba keratitis from 1996 to 2012 at the Francis I. Proctor Foundation.
Results:
Forty-one patients were identified with 42 eyes demonstrating culture proven AK. Annually there were 0 to 3 AK cases from 1996-2004, and 3 to 6 cases from 2005-2011. The number of microbiology positive AK cases has increased since 2005 and shows a significant trend (p=0.003) that has not remitted since the epidemic. The duration of symptoms (weeks) prior to culture-proven AK diagnosis was not statistically different from 1996-2004 (median 4, IQR 3-6) and 2005-2012 (median 4, IQR 2-5.5); Wilcoxon test (p=0.45). The visual acuity at presentation was not significantly different from pre-2005 (median log MAR = 1.35, IQR 0.4-1.75) and 2005 to present (median log MAR = 0.7, IQR 0.4-1.7); Wilcoxon test (p=0.69).
Conclusions:
Since the most recent epidemic of Acanthamoeba keratitis in 2004-2005, there has been an increased number of culture-proven AK that has not decreased to pre-epidemic levels in the Bay Area. Both before and after 2005, patients continue to endure a median of 4 weeks of symptoms prior to AK diagnosis and present with significant visual acuity morbidity. Thus even with the increased awareness of AK, ophthalmologists do not appear to be diagnosing the disease any earlier in its course. More investigation is needed to elucidate the environmental or microbial changes behind the newly increased incidence of Acanthamoeba keratitis.
Keywords: 402 Acanthamoeba