Development of risk factor-based scoring system for detection of hypervirulentKlebsiella pneumoniaebloodstream infections

Background HypervirulentKlebsiella pneumoniae(HVKp) infections have distinct clinical manifestations from classicalK. pneumoniaeinfections. The hallmark of HVKp infections are liver abscess formation and metastatic infections. Due to the severe sequelae of these complications, method to identify patients at-risk of HVKp infections should be developed. Results A retrospective cohort study of 222 patients withK. pneumoniaebloodstream infections (BSIs) was performed. Patient demographics, clinical manifestations, and bacterial characteristics were investigated. Ten cases of liver abscesses were identified. Characteristics such as community-onset BSIs, hypermucoviscosity phenotype, and capsular serotype K1 were identified as risk factors for HVKp infections. A scoring system was developed based on the risk factors. The area under the receiver operating characteristic curve for the scoring system was 0.90. A score of >= 2 points provided sensitivity and specificity of 0.70 and 0.94, respectively. Conclusions Simple scoring system was developed for the diagnosis of HVKp infections. The system allows early identification of patients withK. pneumoniaeBSIs in whom hypervirulent infections should be evaluated. Prospective evaluation is expected.