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Acanthamoeba keratitis is predominantly caused by genotype T4. We report a case of severe keratitis caused by Acanthamoeba in a 39-year-old man who had prior accidental exposure to a corrosive chemical. The patient developed central full thickness ring infiltration and epithelial defect with hypopyon that required keratoplasty. The acanthamoebae isolated from the patient exhibited thermotolerance phenotype with the capability to grow well at ambient temperature and at 42°C. Analysis of a near complete 18S rRNA gene of this isolate revealed a distinct sequence that can be unequivocally assigned to genotype T12, a rare genotype incriminated in corneal infections.
Financial support: This work was supported by the Government Research Budget to Chulalongkorn University (grant no. GB-B-61-061-30-19) and Ratchadapiseksompotch Fund (special project), Chulalongkorn University (grant no. GB-CU-61-23-30-13) to S. J. and C. P.
Authors’ addresses: Vannarut Satitpitakul, Department of Ophthalmology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand, and King Chulalongkorn Memorial Hospital, Bangkok, Thailand, E-mail: email@example.com. Chaturong Putaporntip and Somchai Jongwutiwes, Molecular Biology of Malaria and Opportunistic Parasites Research Unit, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand, E-mails: firstname.lastname@example.org and email@example.com.