Cost-Effectiveness of Targeted Prophylaxis among Allogenic Stem Cell Transplant Recipients.

Bloodstream infections (BSI) are life-threatening complications for onco-hematologic patients. Fluoroquinolones prophylaxis (FQP) was recommended for patients with neutropenia. Later, it was correlated with increased resistance rates among this population and its role became debated. While the role of FQ prophylaxis is still being studied, its cost-effectiveness is also unknown. The objective of this study was to evaluate the costs and effects associated with two alternative strategies (FQP vs. no prophylaxis) for patients with hematological malignancies undergoing allogenic stem cell transplant (HSCT). A decision-tree model was built integrating retrospectively collected data from a single transplant center, part of a tertiary teaching hospital in Northern Italy. Probabilities, costs and effects were considered in the assessment of the two alternative strategies. Probabilities of colonization, BSIs, extended-spectrum beta lactamase (ESBL) and carbapenemase (KPC) BSIs and mortality associated with infection, as well as median duration of length of stay (LOS) were calculated based on data collected between 2013 and 2021. The center applied the strategy of FQP between 2013 and 2016, and of no prophylaxis between 2016 and 2021. Data on 326 patients were collected during the considered time period. Overall, the rates of colonization, BSI, KPC/ESBL BSI, and mortality were 6.8% (95% confidence interval (CI) 2.7-13.5), 42% (9.9-81.4) and 20.72 (16.67-25.26), respectively. A mean bed-day cost of 132€ was estimated. Considering no prophylaxis vs. prophylaxis, the difference in costs ranged between additional 33.61 and 80.59€ per patient, whereas the difference in effects ranged between 0.11 and 0.03 life-years (LYs) lost (around 40 and 11 days). Given the small differences in terms of costs and effects between the two strategies, no prophylaxis seems an appropriate choice. Furthermore, this analysis did not consider the broader effect on hospital ecology of multiple doses of FQP, which could provide further support for the strategy of no prophylaxis. Our results suggest that the necessity for FQP in onco-hematologic setting should be determined based on local antibiotic resistance patterns.