Unusual case of acanthamoeba keratitis in a contact lens wearer.

OBJECTIVE

To present an atypical case of acanthamoeba keratitis in a soft contact lens wearer.

METHODS

A case report of a 28-year-old female soft contact lens wearer with a 6-day history of redness and blurred vision in her right eye. Examination showed stromal keratitis that did not respond to therapy for herpes simplex virus. Four weeks later, the patient had increased stromal infiltration, an endothelial plaque, and a hypopyon. She did not complain of pain apart from mild discomfort. Corneal smears and anterior chamber tap were negative for bacteria, fungi, acanthamoeba, and herpes simplex virus, and the patient was prescribed fortified antibiotics. One week later, a large epithelial defect with a surrounding ring infiltrate was apparent. Corneal biopsy showed acanthamoeba.

RESULTS

The acanthamoeba keratitis resolved with successful treatment. One year later, the patient had a residual visual deficit secondary to stromal scarring and her best-corrected visual acuity was 20/29.

CONCLUSIONS

This case emphasizes the importance of considering acanthamoeba species in the differential diagnosis of keratitis, even without the classic symptom of severe pain. A high degree of suspicion with rapid and appropriate treatment may result in improved recovery of vision.