Huian Ge, Jianhao Su, Gaoxiang Xu, Yanan Li, Zhikang Xiao, Jiaqing Yan, Yigeng Peng, Jianzhong Xu, Chen Qiu, Ri Liu
Polymicrobial KP-BSI occurred in about one-fifth of KP bloodstream infection episodes and was independently associated with MDR status of the index KP isolate, intensive healthcare exposures, metastatic malignancy, and socioeconomic disadvantage.
BACKGROUND: Polymicrobial Klebsiella pneumoniae(KP) bloodstream infection is clinically important and may indicate greater healthcare intensity and antimicrobial resistance. We examined baseline characteristics, prior exposures, and independent risk factors for polymicrobial KP-BSI using a large real-world microbiology dataset.
METHODS: We performed a retrospective cohort study using the Antimicrobial Resistance Monitoring Database (ARMD). Patients with blood culture-confirmed KP and available resistance and admission-source data were included. The final cohort comprised 10,216 patients, classified as monomicrobial KP-BSI or polymicrobial KP-BSI. Demographic and clinical characteristics, prespecified time windows for prior antibiotic exposure and prior infection, and Area Deprivation Index (ADI) state rank were compared. Logistic regression was used to identify factors associated with polymicrobial KP-BSI.
RESULTS: Among 10,216 patients, 1,999 (19.6%) had polymicrobial KP-BSI. Sex differed significantly between groups, whereas age distribution was similar. Polymicrobial infection was associated with a higher frequency of multidrug resistance (MDR) among index KP isolates, greater exposure to invasive care, higher prevalence of major comorbidities, more recent antibiotic exposure and prior infection, and higher ADI state rank. In multivariable analysis, sex, MDR status of the index KP isolate, mechanical ventilation, parenteral nutrition, urethral catheterization, metastatic malignancy, and ADI state rank were independently associated with polymicrobial KP-BSI, whereas mild liver disease was inversely associated. Escherichia coli was the most common copathogen identified in polymicrobial KP-BSI episodes (52%).
CONCLUSIONS: Polymicrobial KP-BSI occurred in about one-fifth of KP bloodstream infection episodes and was independently associated with MDR status of the index KP isolate, intensive healthcare exposures, metastatic malignancy, and socioeconomic disadvantage.