Scleral and intraocular amoebic dissemination in Acanthamoeba keratitis.

PURPOSE

To review an Acanthamoeba keratitis case series for the documented extracorneal spread of the amoeba.

METHODS

A retrospective review of an observational case series from a single institution.

RESULTS

Three patients with 4 instances of microbiologically confirmed extracorneal amoebic spread were identified. Patient 1 had nodular scleritis after undergoing penetrating keratoplasty and was treated successfully with double freeze-thaw cryotherapy; patient 2 had intraocular dissemination of the amoeba detected in a retrocorneal membrane; and patient 3 had, after undergoing tectonic keratoplasty, intraocular dissemination of the amoeba that was treated successfully with intraocular and systemic voriconazole and, afterwards, a nodular scleritis treated with double freeze-thaw cryotherapy and a large-diameter corneal graft to treat corneal recurrence.

CONCLUSIONS

Acanthamoeba can migrate to the sclera or to the intraocular tissues in some instances, such as in long-standing disease or in penetrating keratoplasty. A prompt biopsy for microbiological analysis and early treatment are required, if this is suspected. Voriconazole can be effective for intraocular invasion when used orally and intraocularly. Scleral involvement might require a surgical approach with double freeze-thaw cryotherapy to treat the localized disease.