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Predicting antibiotic resistance in Enterobacterales to support optimal empiric treatment of urinary tract infections in outpatient veterans

Published online by Cambridge University Press:  09 September 2024

Ben J. Brintz*
Affiliation:
Division of Epidemiology, Department of Internal Medicine, University of Utah, Salt Lake City, UT, USAIDEAS Center, VA Salt Lake City Healthcare System, Salt Lake City, UT, USA
Karl Madaras-Kelly
Affiliation:
College of Pharmacy, Idaho State University, Meridian, ID, USAPharmacy Service, Boise VA Medical Center, Boise, ID, USA
McKenna Nevers
Affiliation:
Division of Epidemiology, Department of Internal Medicine, University of Utah, Salt Lake City, UT, USAIDEAS Center, VA Salt Lake City Healthcare System, Salt Lake City, UT, USA
Kelly L. Echevarria
Affiliation:
Pharmacy Benefits Management Program, U.S. Department of Veterans Affairs, Hines, IL, USA
Matthew B. Goetz
Affiliation:
David Geffen School of Medicine at UCLA, Los Angeles, CA, USAVA Greater Los Angeles Healthcare System, Los Angeles, California, USA
Matthew H. Samore
Affiliation:
Division of Epidemiology, Department of Internal Medicine, University of Utah, Salt Lake City, UT, USAIDEAS Center, VA Salt Lake City Healthcare System, Salt Lake City, UT, USA
*
Corresponding author: Ben J. Brintz; Email: ben.brintz@hsc.utah.edu

Abstract

Objective:

Bacterial resistance is known to diminish the effectiveness of antibiotics for treatment of urinary tract infections. Review of recent healthcare and antibiotic exposures, as well as prior culture results is recommended to aid in selection of empirical treatment. However, the optimal approach for assessing these data is unclear. We utilized data from the Veterans Health Administration to evaluate relationships between culture and treatment history and the subsequent probability of antibiotic-resistant bacteria identified in urine cultures to further guide clinicians in understanding these risk factors.

Methods:

Using the XGBoost algorithm, a retrospective cohort of outpatients with urine culture results and antibiotic prescriptions from 2017 to 2022 was used to develop models for predicting antibiotic resistance for three classes of antibiotics: cephalosporins, fluoroquinolones, and trimethoprim/sulfamethoxazole (TMP/SMX) obtained from urine cultures. Model performance was assessed using Area Under the Receiver Operating Characteristic curve (AUC) and Precision-Recall AUC (PRAUC)

Results:

There were 392,647 prior urine cultures identified in 214,656 patients. A history of bacterial resistance to the specific treatment was the most important predictor of subsequent resistance for positive cultures, followed by a history of specific antibiotic exposure. The models performed better than previously established risk factors alone, especially for fluoroquinolone resistance, with an AUC of .84 and PRAUC of .70. Notably, the models’ performance improved markedly (AUC = .90, PRAUC = .87) when applied to cultures from patients with a known history of resistance to any of the antibiotic classes.

Conclusion:

These predictive models demonstrate potential in guiding antibiotic prescription and improving infection management.

Information

Type
Original Article
Creative Commons
Creative Common License - CCCreative Common License - BY
This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, distribution and reproduction, provided the original article is properly cited.
Copyright
© The Author(s), 2024. Published by Cambridge University Press on behalf of The Society for Healthcare Epidemiology of America
Figure 0

Figure 1.Consort diagram showing number of urine cultures and number of unique patients with urine cultures at each step of data cleaning. CDW, Corporate Data Warehouse; NH, Nursing Home.

Figure 1

Table 1.Week intervals used for summarizing antibiotic prescription and culture collection history

Figure 2

Table 2.Summary of unique patients and prior exposures

Figure 3

Figure 2.Receiver operating characteristic (Left) and precision-recall (Right) curves for each predictive model. Trade-off between sensitivity and specificity (Left) and precision and recall (right). Individual points represent performance of referenced risk criteria for exposure or isolation specific to each resistance outcome by color.

Figure 4

Figure 3.Optimal time-window in weeks for prior antibiotic resistance to predict subsequent culture of antibiotic resistance isolates. The week interval x-axis represents the presence of a resistant sample in weekly periods of study. The color and the annotated text represent the gain in area under the receiver operating characteristic curve when the variable is included in the predictive model.

Figure 5

Figure 4.Heat plot presenting the importance of treatment history of a range of antibiotics for predicting the outcomes. The x-axis represents the presence of a resistant isolate in culture at weekly interval. The color and the annotated text represent the gain in AUC when the variable is included in the predictive model.

Figure 6

Figure 5.Heat plot presenting the difference in average SHAP values for antibiotic exposed versus unexposed cases by week interval (x-axis), according to whether or not there is a history of the same antibiotic class exposure in a different weekly interval (y-axis). The color represents the magnitude of difference, i.e., the interaction effect. Blue suggests that the effect of the treatment on the prediction is lessened among individuals who have a history of treatment during a different week interval. In some circumstances, predictive power was reduced when individuals received treatment during multiple time intervals. eg, the -.44 in the middle panel at the 4 on the x-axis and 2 on the y-axis suggests that the difference in average Shapley Additive Explanations value between those having received fluoroquinolones (FQ) treatment 2–4 weeks prior and not having received FQ treatment 2–4 weeks prior decreases by .44 in those who also had treatment with FQ 1–2 weeks ago.

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