Genotypic diversity of Acanthamoeba strains isolated from Chilean patients with Acanthamoeba keratitis.

Authors:
Carolina Aguayo
Carolina Aguayo
Public Health Institute of Chile
Santiago | Chile
Jaime Lagos
Jaime Lagos
Public Health Institute of Chile
Antonio Osuna
Antonio Osuna
Hospital Virgen de las Nieves
Spain

Parasit Vectors 2019 Jan 25;12(1):58. Epub 2019 Jan 25.

Subdepartamento de Genética Molecular, Instituto de Salud Pública de Chile, Av. Marathon 1000, Ñuñoa, CP 7780050, Santiago, Chile.

Background: Acanthamoeba spp. are the causative agents of a severe keratitis occurring mainly in contact lens wearers. The genus comprises more than 24 species that are currently divided into 20 different genotypes (T1-T20) according to sequence variations in the 18S rRNA gene. The objective of this study was to identify the genotypes and sub-genotypes of Acanthamoeba isolates collected at the Parasitology Laboratory of the Public Health Institute of Chile, the only laboratory in the country where Acanthamoeba screening is performed. This is the first report of genotypic identification of clinical isolates of Acanthamoeba in Chile and one of the few in South America.

Results: In this study, 114 Acanthamoeba isolates from 76 Acanthamoeba keratitis patients, obtained between 2005-2016, were genotyped. T4 was the predominant genotype; T2 and T11 genotypes, which are scarcely reported worldwide, were also identified in Chilean patients (one and two patients, respectively). This is the first report of T2 and T11 genotypes isolated from Acanthamoeba keratitis patients in South America. It is also the first report of the T2 genotype circulating in this continent. Analysis of the diagnostic fragment 3 region of the 18S rRNA gene showed 24 T4 variants, with a predominance of the sub-genotype T4/A, followed by T4/B, T4/G, T4/C and T4/D. Bayesian analysis revealed three groups among the T4 variants: two well supported groups that included 12 and 7 sub-genotypes, respectively, and a weakly supported group that included 5 sub-genotypes. Most of the predominant T4 sub-genotypes belonged to the same group, which included 71.3% of the patients, while some minority variants lied mainly in the other two clusters.

Conclusions: T2, T4 and T11 genotypes were predominantly isolated from the Acanthamoeba keratitis patients in Chile. Chilean predominant T4 sub-genotypes, which have also been reported worldwide, formed a separate cluster of the minority T4 variants. This study provides useful information about the predominant genotypes and subgenotypes that would be useful in selecting suitable strains to develop immunological and/or molecular diagnostic assays in Chile.

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http://dx.doi.org/10.1186/s13071-019-3302-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6346584PMC
January 2019
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References

(Supplied by CrossRef)
Article in Am J Ophthalmol
JKG Dart et al.
Am J Ophthalmol 2009
Article in Lancet
J Nagington et al.
Lancet 1974
Article in Cornea
NJR Maycock et al.
Cornea 2016
Article in J Eukaryot Microbiol
RJ Gast et al.
J Eukaryot Microbiol 1996
Article in J Eukaryot Microbiol
PA Fuerst et al.
J Eukaryot Microbiol 2015
Article in Parasitol Res
D Corsaro et al.
Parasitol Res 2017
Article in J Eukaryot Microbiol
DR Stothard et al.
J Eukaryot Microbiol 1998
Article in J Clin Microbiol
JM Schroeder et al.
J Clin Microbiol 2001
Article in J Clin Microbiol
GC Booton et al.
J Clin Microbiol 2002
Article in Parasite
J Lorenzo-Morales et al.
Parasite 2015
Article in J Eukaryot Microbiol
J Walochnik et al.
J Eukaryot Microbiol 2015

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