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Arianna Tavanti

Publications and source records attributed to Arianna Tavanti.

2 recordsLinked to original sources

Evolution of Candidaemia and azole resistance in Italy: A multicentre retrospective study.

PURPOSE: Candidaemia is the most common healthcare-associated invasive fungal infection. The evolution of the epidemiology of candidaemia in Italy has not been assessed, except at the local level. The primary objective of this study is monitoring changes in the epidemiology of candidaemia and in the susceptibility profiles of Candida isolates between 2015 and 2023. METHODS: This retrospective multicentre study (2015-2023), involved 11 tertiary-care hospital microbiology laboratories across the Italian country. The confirmed candidaemia episodes were included and demographic data, hospital ward, species identification, and antifungal susceptibility profiles (Sensititre Yeast One) were collected. RESULTS: 6,927 candidaemia cases were identified; incidence increased from 1.1/1000 hospitalisations in 2017 to 2.3/1000 in 2020-2021, peaking during the COVID-19 pandemic, and declined in 2023 while remaining above prepandemic levels. Patients older than 65 years accounted for most infections. Medical wards represented the main setting of occurrence, followed by intensive care units, especially during pandemic years. C. albicans remained the most common species (45.4%), followed by C. parapsilosis (24.7%), C. glabrata (11.8%), and C. tropicalis (11.4%). Echinocandin resistance remained low (<&#x2009;2% for C. albicans and C. glabrata), whereas azole resistance increased markedly, particularly in C. parapsilosis, reaching fluconazole resistance rates of 25.6% in 2022. CONCLUSIONS: Candidaemia increased during the 9-year study period in Italy, particularly in the COVID-19 pandemic, in medical wards and ICU. Emerged a growing azole resistance, underscoring the need for enhanced surveillance and informed empirical treatment strategies.

Candida species etiology

Population structure and properties of Candida albicans, as determined by multilocus sequence typing.

We submitted a panel of 416 isolates of Candida albicans from separate sources to multilocus sequence typing (MLST). The data generated determined a population structure in which four major clades of closely related isolates were delineated, together with eight minor clades comprising five or more isolates. By Fisher's exact test, a statistically significant association was found between particular clades and the anatomical source, geographical source, ABC genotype, decade of isolation, and homozygosity versus heterozygosity at the mating type-like locus (MTL) of the isolates in the clade. However, these associations may have been influenced by confounding variables, since in a univariate analysis of variance, only the clade associations with ABC type and anatomical source emerged as statistically significant, providing the first indication of possible differences between C. albicans strain type clades and their propensity to infect or colonize different anatomical locations. There were no significant differences between clades with respect to distributions of isolates resistant to fluconazole, itraconazole, or flucytosine. However, the majority of flucytosine-resistant isolates belonged to clade 1, and these isolates, but not flucytosine-resistant isolates in other clades, bore a unique mutation in the FUR1 gene that probably accounts for their resistance. A significantly higher proportion of isolates resistant to fluconazole, itraconazole, and flucytosine were homozygous at the MTL, suggesting that antifungal pressure may trigger a common mechanism that leads both to resistance and to MTL homozygosity. The utility of MLST for determining clade assignments of clinical isolates will form the basis for strain selection for future research into C. albicans virulence.

Analysis of Variance