Antimicrob Agents Chemother. 2021 Jun 1:AAC0079321. doi: 10.1128/AAC.00793-21. Online ahead of print.
ABSTRACT
Background: Stenotrophomonas maltophilia bloodstream infections (BSI) are associated with considerable mortality in the hematologic malignancy population. Trimethoprim-sulfamethoxazole (TMP-SMX) is the treatment of choice, however, it is not routinely included in empiric treatment regimens both because of its adverse event profile and the relative rarity of S. maltophilia infections. We developed a risk score to predict hematologic malignancy patients at increased risk for S. maltophilia BSI to guide early (TMP-SMX) therapy. Methods: Patients ≥12 years of age admitted to five hospitals between 7/2016 and 12/2019 were included. Two separate risk scores were developed: (1) a “knowledge-driven” risk score based upon previously identified risk factors in the literature in addition to variables identified by regression analysis using the current cohort and (2) a risk score based upon automatic variable selection. For both scores, discrimination (ROC curves and C statistics) and calibration (Hosmer-Lemeshow goodness of fit test and graphical calibration plots) were assessed. Internal validation was assessed using leave-one-out cross-validation. Results: 337 unique patients were included; 21 (6.2%) had S. maltophilia BSI. The knowledge-driven risk score (acute leukemia, absolute neutrophil count category, mucositis, central line, and ≥3 days of carbapenem therapy) had superior performance (C-statistic=0.75; 0.71 after cross-validation) compared to the risk score utilizing automatic variable selection (C-statistic=0.63; 0.38 after cross-validation). Conclusions: A user-friendly risk score incorporating five variables easily accessible to clinicians performed moderately well to predict hematologic malignancy patients at increased risk for S. maltophilia BSI. External validation using a larger cohort is necessary to create a refined risk score before broad clinical application.
PMID:34060899 | DOI:10.1128/AAC.00793-21
