Acanthamoeba T4 genotype associated with keratitis infections in Tunisia

Acanthamoeba keratitis (AK) is a sight-threatening infection. We report five cases of AK diagnosed from 2005 to 2009 in the Laboratory of Parasitology-Mycology at Habib Bourguiba Sfax Hospital, Tunisia. All were associated with improper care of contact lenses (rinsing of contact lenses with tap water and inappropriate cleaning) and lens storage. The patients displayed different clinical presentations: corneal inflammation, corneal ulceration, and corneal abscess. The diagnosis was made after direct examination, culture, and polymerase chain reaction amplification with specific primers. The genotype classification was based on the highly variable DF3 region in the 18S rRNA gene. This is the first study characterizing Acanthamoeba genotype in Tunisia and North Africa. All Acanthamoeba isolates were associated to the T4 genotype. Three different DF3 sequence types were related to AK infections T4/10, T4/15, and T4/16.