Évolution épidémiologique et profils microbiologiques des candidémies aux cliniques universitaires Saint-Luc (2014-2024)

Details

Supervisors

Rodriguez-Villalobos, Hector

Faculty

Faculté de pharmacie et des sciences biomédicales

Degree label

Master [120] en sciences biomédicales, à finalité spécialisée: sciences biomédicales cliniques

Abstract

enBackground: Candidemia is one of the leading nosocomial invasive fungal infections and is associated with high mortality. Changes in the epidemiology of Candida species and the emergence of antifungal resistance highlight the importance of continuous microbiological surveillance. This study aimed to describe the epidemiological trends of candidemia diagnosed at Cliniques universitaires Saint-Luc between 2014 and 2024, to analyse antifungal susceptibility profiles and minimum inhibitory concentrations (MICs), and to characterize the main clinical features of affected patients. Methods: A retrospective single-centre study was conducted using microbiological data and medical records of patients diagnosed with candidemia between January 1, 2014, and December 31, 2024. After grouping blood culture isolates belonging to the same infectious episode, 278 episodes corresponding to 288 isolates from 267 patients were included in the microbiological analysis. Following the exclusion of incomplete medical records, 254 patients were retained for the clinical analysis. Analyses included temporal trends in candidemia, species distribution, antifungal susceptibility profiles and MICs, clinical characteristics, risk factors, diagnostic departments, antifungal treatment strategies, time to initiation of antifungal therapy, and in-hospital survival. Statistical analyses were performed using the chi-square test, Fisher's exact test, Wilcoxon or Kruskal–Wallis tests, logistic regression to assess fluconazole resistance, and Kaplan–Meier survival analysis. Results: Candida albicans remained the predominant species (52.8%), followed by Candida glabrata (21.5%), Candida parapsilosis (9.0%), and Candida tropicalis (7.6%). No significant changes were observed in species distribution over the study period (p = 0.084), nor in the proportion of C. albicans versus non-albicans Candida candidemia (p = 0.879). Likewise, no significant increase in fluconazole resistance was detected between 2014 and 2024 (p = 0.792). However, susceptibility profiles differed significantly according to species (p < 0.001), with non-albicans Candida species exhibiting an approximately seven-fold higher risk of fluconazole resistance than C. albicans (OR = 7.0; 95% CI: 2.34–20.97; p < 0.001). Echinocandins and amphotericin B retained excellent in vitro activity, whereas higher azole MICs were observed for Candida glabrata and Candida krusei. Candidemia was mainly diagnosed in intensive care, haematology, and oncology departments. The most common risk factors were prior antibacterial therapy (94.8%), the presence of a central venous catheter (68.8%), immunosuppression (63.5%), recent surgery (61.1%), and admission to the intensive care unit (63.6%). Fluconazole was the most frequently prescribed initial antifungal treatment (54.3%), followed by anidulafungin (27.2%) and caspofungin (15.4%). The median time from the first positive blood culture to initiation of antifungal therapy was two days, with no significant difference between the study groups. Kaplan–Meier survival analysis showed no significant difference in in-hospital survival between patients with C. albicans candidemia and those with non-albicans Candida candidemia. Overall in- hospital mortality reached 66.1%, whereas only 10.6% of deaths were considered directly attributable to candidemia. Conclusion: This study demonstrates the stability of candidemia epidemiology and overall antifungal resistance patterns at Cliniques universitaires Saint-Luc between 2014 and 2024, with persistent predominance of Candida albicans and sustained excellent activity of echinocandins. However, fluconazole resistance differed significantly according to species, with non-albicans Candida species exhibiting a substantially higher risk of resistance than C. albicans. Clinically, candidemia mainly affected patients hospitalized in critical care or specialized departments who presented with multiple predisposing risk factors, while overall in-hospital mortality remained high despite a relatively low proportion of deaths being directly attributable to candidemia. These findings highlight the value of continuous microbiological and clinical surveillance to improve the understanding of local epidemiology and to guide diagnostic and therapeutic strategies.