Clinical and molecular features of candidemia: a three-year retrospective study in Northern Guizhou, China

Candidemia, a life-threatening infection with rising incidence and substantial mortality, necessitates improved management strategies. This study aimed to investigate the clinical features, species distribution, risk factors, antifungal susceptibility, and molecular epidemiology of Candida albicans isolates from candidemia patients over a three-year period.

This retrospective study included 133 patients with candidemia from a teaching hospital in Guizhou, China between December 2019 and November 2022. Clinical data were compared between C. albicans (n = 63) and non-C. albicans (NAC) (n = 70) groups. Risk factors and prognostic biomarkers were identified using logistic regression and ROC analysis. Multilocus sequence typing (MLST) was performed for C. albicans isolates.

NAC species predominated (52.6%) over C. albicans (47.4%). The 30-day all-cause mortality was 48.1%, higher in C. albicans infections. For C. albicans, hypoalbuminemia and septic shock were independent mortality risk factors, while antifungal therapy and higher platelets were protective. For NAC, septic shock and elevated serum urea were risk factors. Prognostic biomarkers included D-dimer and CRP for C. albicans, and serum urea and total bilirubin for NAC. Most isolates were antifungal-susceptible, though C. glabrata and C. tropicalis showed increased azole non-susceptibility. MLST of 48 C. albicans isolates identified 7 novel alleles and 23 new DST types. CC9 was the predominant clonal complex. CC138 and CC139 are newly reported clonal complexes.

This study confirms that candidemia remains a serious threat with high mortality. The distinct risk factors and prognostic biomarkers between C. albicans and non-C. albicans species indicate the need for species-specific management. Although overall resistance remains low, emerging azole non-susceptibility in key species underscores the necessity for continuous susceptibility surveillance. MLST revealed a highly diverse and evolving C. albicans population, including novel genetic lineages. Integrating molecular epidemiology with clinical data is crucial for advancing global candidemia management.