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Published on: June 12, 2014
Acanthamoeba keratitis with symbiosis of Hartmannella ameba
1Department of Ophthalmology, Osaka University Medical School, Suitasi, Japan.
Purpose:
To report a case of severe amebic keratitis in which both Hartmannella and Acanthamoeba were isolated simultaneously from the same lesion.
Method:
Case report. The deep corneal lesion was scraped for cytopathology and isolation of the pathogens. We tested the in vitro sensitivities of the pathogens to several drugs.
Results:
Cultures of the corneal scrapings and of the solution in the patient's contact lens storage case were positive for Acanthamoeba E9 cysts and trophozoites. Hartmannella ameba coexisted with Acanthamoeba in the cornea. When tested in vitro, Acanthamoeba trophozoites were sensitive to both miconazole nitrate and natamycin, while cysts were sensitive only to natamycin. However, the patient did not respond to these antiamebic drugs.
Conclusions:
This case suggests that Acanthamoeba is not the only origin of amebic keratitis. Hartmannella may also cause severe drug-resistant keratitis.
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