P473 Genomic epidemiology of antifungal-resistant Candida auris in Colombia

Abstract

Abstract Poster session 1, September 21, 2022, 12:30 PM - 1:30 PM Introduction Candida auris is a public health threat. Five major clades of C. auris have been identified (Clades I–V). In Colombia, C. auris infections were first reported in 2016 with ongoing transmission reported from multiple cities. Here, we describe C. auris genomic epidemiology in Colombia detailing cases from 2016–2021. Methods A total of 99 isolates from C. auris cases were collected between June 2016 to January 2021 in Colombia, representing 11 geographic locations. Species confirmation, antifungal susceptibility testing, and whole-genome sequencing (WGS) were performed. In all, 37 genomic sequences generated previously from isolates from C. auris cases in Colombia, Venezuela, Panama, Israel, and United States were also analyzed MycoSNP workflow was used to assess sequence quality, map reads to the reference, and identify single-nucleotide polymorphisms (SNPs). Pairwise distances and a neighbor-joining tree were generated. IQtree was used to generate a maximum-likelihood tree with bootstrap values. Results Phylogenetic analysis identified 1 493 SNP positions. Isolates from Colombia clustered to Clade IV and predominately grouped by country except for 16 fluconazole-resistant isolates from Bogota, Colombia that grouped with five isolates from Venezuela. In this cluster, 20 (95%) were resistant to fluconazole and 5 (24%) were resistant to fluconazole and the echinocandin micafungin. Remaining isolates from Bogota did not group in this cluster and were susceptible to fluconazole and micafungin. A total of 98 isolates from Colombia clustered together. Within this Colombian cluster, there were two subgroups that had bootstrap support of 100% and were separated by 13 SNPs. The first subgroup was a cluster that contained 18 isolates from the north coast; 17 (94%) isolates were resistant to amphotericin B. A second subgroup consisted of 26 isolates from Cesar and Norte de Santander, and 22 (84%) isolates were resistant to fluconazole. Conclusions Based on the phylogenetic reconstruction, C. auris in Colombia continues to be of Clade IV. Amphotericin B-resistant isolates were predominately from the north coast, fluconazole-resistant isolates were from a wider geographic area in Colombia, and echinocandin-resistant isolates were from Bogota. Within the Colombian cluster comprising two subgroups, we observed high genetic relatedness between isolates from different geographic locations suggesting transmission among cities.