Six-year retrospective analysis of the epidemiology and risk factors of multidrug-resistant bloodstream infections in oncology patients in Jiangxi, China

Cancer patients are particularly vulnerable to bloodstream infections (BSIs) due to their immunocompromised status. This retrospective study at Jiangxi Cancer Hospital (2019 to 2024) analyzed the bacterial spectrum, risk factors, and antimicrobial susceptibility profiles of BSIs in cancer patients. Logistic regression analysis was performed to identify risk factors associated with multidrug resistance (MDR) in Gram-positive and Gram-negative infections. A total of 1,161 bacteria were isolated from 954 oncological patients in 1,095 BSI episodes. Among these, 62.79% were Gram-negative bacteria, with <i>Escherichia coli</i> (40.88%) and <i>Klebsiella pneumoniae</i> (19.07%) being the most prevalent. Gram-positive bacteria accounted for 37.21% of isolates, with <i>Staphylococcus aureus</i> (26.16%) being the most common. Gram-negative infections were more prevalent in patients with breast, gastrointestinal, hepatobiliary, and pancreatic cancers, whereas Gram-positive infections were more common among those with lymphoma, head and neck, and lung cancers, as well as in patients undergoing invasive procedures. High resistance rates were observed against ampicillin, piperacillin, cefazolin, and erythromycin, whereas tigecycline and nitrofurantoin exhibited low resistance rates among the tested bacterial isolates. Among Gram-negative bacteria, 5.48% were carbapenemase producers and 15.36% were extended-spectrum β-lactamase (ESBL) producers. Moreover, methicillin resistance was observed in 36.04% of <i>Staphylococcus aureus</i> and 66.83% of coagulase-negative <i>Staphylococcus</i> isolates. MDR was observed in 40.19% of Gram-negative and 50.92% of Gram-positive infections. Hypoproteinemia (OR 3.2) was identified as an independent risk factor for MDR-BSIs caused by Gram-negative bacteria. The high prevalence of MDR bacteria in BSIs among cancer patients highlights the necessity of individualized treatment and continuous monitoring in oncology settings.IMPORTANCEThis study addresses a critical gap in understanding the epidemiology and risk factors of multidrug-resistant bloodstream infections (MDR-BSIs) in oncology patients from a high-burden region of China. By analyzing over a thousand BSI episodes over 6 years, the study identifies the predominant bacterial species, their resistance profiles, and key clinical and procedural risk factors associated with MDR. The high rates of MDR among both Gram-negative and Gram-positive pathogens underscore the urgent need for tailored antimicrobial stewardship, infection control interventions, and individualized treatment strategies. These findings provide essential evidence for guiding empirical antibiotic choices and improving infection management protocols in cancer care settings.