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Quantification of Acanthamoeba spp. Motility
Published on: September 20, 2024
Acanthamoeba keratitis: a parasite on the rise
Nuthida Thebpatiphat1, Kristin M Hammersmith, Fabiano N Rocha
1Cornea Service, Wills Eye Hospital, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA.
Cornea
|June 27, 2007
Summary
Acanthamoeba keratitis (AK) incidence increased significantly, even with proper contact lens (CL) care. Advanced stromal disease at diagnosis indicates a poorer visual outcome for AK patients.
Area of Science:
- Ophthalmology
- Infectious Diseases
- Microbiology
Background:
- Acanthamoeba keratitis (AK) is a serious eye infection.
- Contact lens wear is a primary risk factor for AK.
- Understanding trends and risk factors is crucial for prevention and treatment.
Purpose of the Study:
- To report a significant increase in Acanthamoeba keratitis (AK) cases.
- To identify risk factors, clinical features, treatments, and outcomes of AK.
- To analyze trends in AK incidence between 2004-2005.
Main Methods:
- Retrospective case series of 20 eyes with AK.
- Data collected on incidence (1995-2005), visual acuity, risk factors (CL use, water exposure), diagnosis, and treatment.
- Analysis of clinical presentation and patient outcomes.
Main Results:
- Statistically significant increase in AK incidence in 2004-2005 (P < 0.01).
- All AK patients wore contact lenses (CL); most used frequent-replacement soft CL with multipurpose solutions.
- Risk factors included well water exposure (40%), swimming with CL (25%), and overnight wear (25%). Misdiagnosis as herpes simplex virus occurred in 70%.
Conclusions:
- An increased incidence of AK was observed.
- AK can develop despite proper contact lens (CL) hygiene and multipurpose solution use.
- Advanced stromal disease at diagnosis is linked to worse visual outcomes.
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