Phenotypic and Molecular Characterization of Multidrug-Resistant Clinical Isolates of the Candidozyma haemuli Species Complex (Formerly Candida haemulonii Species Complex) from the Brazilian Amazon Reveals the First Case of Candidozyma pseudohaemuli in Brazil.

Abstract

This study included 24 isolates of the Candidozyma haemuli species complex from patients in the Brazilian Amazon between 2021 and 2024. These isolates were identified by sequencing as C. duobushaemuli (54.2%), C. haemuli sensu stricto (29.2%), C. haemuli var. vulneris (12.5%), and C. pseudohaemuli (4.2%). The finding of C. pseudohaemuli represents the first case reported in Brazil. Haplotype and phylogenetic analysis of these species, along with other isolates from Brazil, revealed low intraspecific genetic diversity. Resistance to at least one antifungal was observed in 83.3% of isolates, with multidrug resistance in 58.3%, including one isolate resistant to all tested antifungals. The isolates demonstrated active biofilm production, lytic enzyme activity, and thermotolerance. Notably, one C. duobushaemuli isolate exhibited tolerance to 42 °C, a phenotype not previously described. It is crucial for Brazil and other countries to recognize the emergence of these species as a public health threat and to take proactive measures to prevent outbreaks.