Laura Theill1, Catiana Dudiuk2, Soraya Morales-Lopez3, Indira Berrio4, José Yesid Rodríguez5, Adriana Marin6, Soledad Gamarra1, Guillermo Garcia-Effron7. 1. Laboratorio de Micología y Diagnóstico Molecular - Cátedra de Parasitología y Micología - Facultad de Bioquímica y Ciencias Biológicas - Universidad Nacional del Litoral, Santa Fe, Argentina. 2. Laboratorio de Micología y Diagnóstico Molecular - Cátedra de Parasitología y Micología - Facultad de Bioquímica y Ciencias Biológicas - Universidad Nacional del Litoral, Santa Fe, Argentina; Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), CCT-Santa Fe, Argentina. 3. Universidad Popular del Cesar, Valledupar, Colombia; Laboratorios Nancy Flórez García S.A.S, Valledupar, Colombia. 4. Medical and Experimental Mycology Group, Corporación para Investigaciones Biológicas (CIB), Medellín, Colombia; Hospital General de Medellín "Luz Castro de Gutiérrez" ESE, Medellín, Colombia. 5. Centro de Investigaciones Microbiológicas del Cesar - CIMCE Ltda, Valledupar, Colombia. 6. Clínica General del Norte, Barranquilla, Colombia. 7. Laboratorio de Micología y Diagnóstico Molecular - Cátedra de Parasitología y Micología - Facultad de Bioquímica y Ciencias Biológicas - Universidad Nacional del Litoral, Santa Fe, Argentina; Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), CCT-Santa Fe, Argentina. Electronic address: ggarcia@unl.edu.ar.
Abstract
BACKGROUND: Candida auris and Candida haemulonii are emerging and multiresistant pathogens. C. auris has produced hospital outbreaks and is misidentified by phenotypic-based methods. The only reliable identification methods are DNA sequencing and MALDI-TOF. AIMS: To develop a classical-PCR method capable of rapidly and accurately identify C. auris and C. haemulonii. METHODS: A multiplex PCR was carried out in one tube that included an internal control and oligonucleotides that specifically hybridize to the ITS2 region of C. auris and C. haemulonii. The usefulness of the new method was verified by testing a collection of 50 strains of 20 different species (previously identified by ITS sequencing). The selection of species was made in order to emulate the C. auris panel used by the CDC to validate diagnostic tools. In addition, other yeast species not included in the aforementioned panel were incorporated based on reported identification errors. RESULTS: The results obtained with the proposed protocol were in total agreement with those obtained by ITS sequencing. CONCLUSIONS: We present a PCR method able to unequivocally identify C. auris and differentiate it from C. haemulonii. It is inexpensive, fast and it could be a useful tool to reduce the chances of a C. auris outbreak.
BACKGROUND:Candida auris and Candida haemulonii are emerging and multiresistant pathogens. C. auris has produced hospital outbreaks and is misidentified by phenotypic-based methods. The only reliable identification methods are DNA sequencing and MALDI-TOF. AIMS: To develop a classical-PCR method capable of rapidly and accurately identify C. auris and C. haemulonii. METHODS: A multiplex PCR was carried out in one tube that included an internal control and oligonucleotides that specifically hybridize to the ITS2 region of C. auris and C. haemulonii. The usefulness of the new method was verified by testing a collection of 50 strains of 20 different species (previously identified by ITS sequencing). The selection of species was made in order to emulate the C. auris panel used by the CDC to validate diagnostic tools. In addition, other yeast species not included in the aforementioned panel were incorporated based on reported identification errors. RESULTS: The results obtained with the proposed protocol were in total agreement with those obtained by ITS sequencing. CONCLUSIONS: We present a PCR method able to unequivocally identify C. auris and differentiate it from C. haemulonii. It is inexpensive, fast and it could be a useful tool to reduce the chances of a C. auris outbreak.
Authors: Diego H Caceres; Kaitlin Forsberg; Rory M Welsh; David Joseph Sexton; Shawn R Lockhart; Brendan R Jackson; Tom Chiller Journal: J Fungi (Basel) Date: 2019-11-28