A TTP-incorporated scoring model for predicting mortality of solid tumor patients with bloodstream infection caused by Escherichia coli.

BACKGROUND: Few mortality-scoring models are available for solid tumor patients who are predisposed to develop Escherichia coli-caused bloodstream infection (ECBSI). We aimed to develop a mortality-scoring model by using information from blood culture time to positivity (TTP) and other clinical variables. METHODS: A cohort of solid tumor patients who were admitted to hospital with ECBSI and received empirical antimicrobial therapy was enrolled. Survivors and non-survivors were compared to identify the risk factors of in-hospital mortality. Univariable and multivariable regression analyses were adopted to identify the mortality-associated predictors. Risk scores were assigned by weighting the regression coefficients with corresponding natural logarithm of the odds ratio for each predictor. RESULTS: Solid tumor patients with ECBSI were distributed in the development and validation groups, respectively. Six mortality-associated predictors were identified and included in the scoring model: acute respiratory distress (ARDS), TTP ≤ 8 h, inappropriate antibiotic therapy, blood transfusion, fever ≥ 39 °C, and metastasis. Prognostic scores were categorized into three groups that predicted mortality: low risk (< 10% mortality, 0-1 points), medium risk (10-20% mortality, 2 points), and high risk (> 20% mortality, ≥ 3 points). The TTP-incorporated scoring model showed excellent discrimination and calibration for both groups, with AUC being 0.833 vs 0.844, respectively, and no significant difference in the Hosmer-Lemeshow test (6.709, P = 0.48) and the chi-square test (6.993, P = 0.46). Youden index showed the best cutoff value of ≥ 3 with 76.11% sensitivity and 79.29% specificity. TTP-incorporated scoring model had higher AUC than no TTP-incorporated model (0.837 vs 0.817, P < 0.01). CONCLUSIONS: Our TTP-incorporated scoring model was associated with improving capability in predicting ECBSI-related mortality. It can be a practical tool for clinicians to identify and manage bacteremic solid tumor patients with high risk of mortality.

Clinical outcome of Escherichia coli bloodstream infection in cancer patients with/without biofilm formation: a single-center retrospective study.

BACKGROUND: Extended-spectrum ß-lactamase-producing Escherichia coli (ESBL-EC) is one of the main antimicrobial-resistant pathogens. Little data are available on how biofilm formation (BF) contributes to EC-caused bloodstream infection (BSI) in cancer patients. This study investigated the impact of BF on clinical outcomes of cancer patients with EC-caused BSI. METHODS: Clinical outcome and microbiological characteristics including the presence of bla genes in ESBL-EC isolates were retrospectively collected from BSI cancer patients. Patients infected with ESBL-EC were compared with patients infected with third-generation cephalosporin-susceptible strains. Survival curves were generated by Kaplan-Meier analysis and the survival difference was assessed by the log-rank test. Risk factors for ESBL-EC infection, predictors of mortality, and outcome differences were determined by multivariate logistic regression and Cox regression analysis, respectively. RESULTS: A high prevalence of ESBL-EC with dominant bla CTX-M-15, bla CTX-M-15 plus bla TEM-52 genotype was found in BSI cancer patients. Independent risk factors for infection with ESBL-EC were cephalosporins, chemotherapy, and BF. Metastasis, ICU admission, BF-positive ESBL-EC, organ failure, and the presence of septic shock were revealed as predictors for mortality. The ESBL characteristic was associated with the BF phenotype, and the overall mortality was significantly higher in cancer patients with BF-positive ESBL-EC-caused BSI. CONCLUSION: bla CTX-M-15 type ESBL-EC is highly endemic among cancer patients with BSI. BF is associated with multi-drug resistance by ESBL-EC and is also an independent risk factor of mortality for cancer patients with BSI. Our findings suggest that the combination of BF-positive ESBL-EC isolates with other appropriate laboratory indicators might benefit infection control and improve clinical outcomes.