Skip Navigation LinksHome > February 2014 - Volume 33 - Issue 2 > Clinical Characteristics of Acanthamoeba Keratitis Infection...
doi: 10.1097/ICO.0000000000000014
Clinical Science

Clinical Characteristics of Acanthamoeba Keratitis Infections in 28 States, 2008 to 2011

Ross, Jonathan MD*; Roy, Sharon L. MD, MPH*; Mathers, William D. MD; Ritterband, David C. MD; Yoder, Jonathan S. MPH*; Ayers, Tracy MS*; Shah, Rupa D. MD§; Samper, Monika E. RN; Shih, Carolyn Y. MD, MBA; Schmitz, Ann DVM, AM**; Brown, Allison C. PHD, MPH*

Supplemental Author Material
Collapse Box


Purpose: The aim was to describe a geographically and clinically diverse sample of cases of Acanthamoeba keratitis (AK) and establish the risk factors for poor outcomes among patients with this disease.

Methods: We conducted a retrospective, population-based case series of 116 patients with AK identified through a national surveillance network. Data were collected via a medical record review by diagnosing ophthalmologists and by phone interviews with patients. Exact logistic regression modeling was used to determine risk factors for poor visual outcomes.

Results: Among patients with data available on contact lens use, it was found that 93.3% wore contact lenses. The median time from symptom onset to care seeking was 2 days, whereas the median time from symptom onset to diagnosis was 27 days. Keratoplasty was performed in 27 of 81 patients with available outcome data and was more likely in patients >40 years old [odds ratio (OR) 5.25, 95% confidence interval (CI) 1.49–21.92]. When adjusted for age, the risk factors for keratoplasty included the presence of a ring infiltrate (OR 40.00, 95% CI 3.58–447.0) or any sign of stromal invasion (OR 10.48, 95% CI 2.56–55.09). One-third of patients with available data on best-corrected visual acuity had a best-corrected visual acuity <20/200, with the presence of a ring infiltrate as the only significant predictor of this outcome when adjusted for age (aOR 3.45, 95% CI 1.01–12.31).

Conclusions: AK remains challenging to diagnose. Consequently, patients with advanced disease are more likely to have poor outcomes, particularly if they are older. The increasing awareness of AK among general eye care providers may shorten referral times and potentially improve outcomes.

© 2014 by Lippincott Williams & Wilkins.


Article Tools


Article Level Metrics

Search for Similar Articles
You may search for similar articles that contain these same keywords or you may modify the keyword list to augment your search.