Clinical characteristics and risk factors for mixed bloodstream infection with Candida and bacteria in a three-A hospital from 2011 to 2022

OBJECTIVE To observe the differences in etiological, clinical characteristics and treatment outcomes between the mixed and simple bloodstream infection with Candida and explore the risk factors for the mixed infections. METHODS By means of retrospective case-control study, the clinical data were collected from 130 patients with Candida bloodstream infection who were treated in Guangdong Provincial People's Hospital from Jan. 2011 to Dec. 2022. The enrolled patients were divided into the mixed infection group with 71 cases and the simple infection group with 59 cases according to the status of bacterial infection complication. The distribution of pathogens, underlying diseases and treatment outcomes were observed and compared between the two groups. Univariate analysis and multivariate logistic regression analysis were performed for the risk factors for the mixed infections. RESULTS Candida tropicalis (44.07%) and Candida albicans (38.98%) were dominant in the simple infection group; the isolation rate of C. albican was highest (40.85%) in the mixed infection group, and the complication with bacterial and Staphylococcus spp was most common (29.87%). The overall nosocomial mortality rate of the patients with Candida bloodstream infection was 51.5%(67/130); the mortality rate was 54.24%(32/59) in the simple Candida infection group, 49.30%(35/71) in the mixed infection group, and there was no significant difference in the mortality rate between the two groups. The result of multivariate logistic regression analysis indicated that the age(OR=1.029,95%CI:1.002 to 1.057,P=0.036), hormonotherapy (OR=14.217,95%CI:2.232 to 90.568,P=0.005) and ventilator support(OR=6.623,95%CI:1.016 to 43.150,P=0.048) were the independent risk factors for the mixed bloodstream infections with Candida and bacteria, while the chronic liver disease was the protective factor(OR=0.047,95%CI:0.004 to 0.562,P=0.016). CONCLUSIONS The mortality rate of the patients with Candida bloodstream infection is high. The patients with the mixed infections of Candida and Staphylococcus spp are common. The age, hormonotherapy and ventilator support are the independent risk factors for the mixed infections.