Antibiotic costs in bacteremic and nonbacteremic patients treated with the de-escalation approach

Introduction

Antibiotic therapy significantly contributes to healthcare costs and especially to those infections due to multidrug resistance pathogens. The purpose of the study was to investigate empiric antibiotic therapy costs compared with the consequent application of de-escalated therapy.

Methods

We prospectively collected data regarding demographics and antibiotic costs in critically ill ICU patients experiencing infection. We recorded daily costs of empiric antibiotic therapy on identification–suspicion of infection as well as the costs after the pathogen identification and susceptibility.

Results

We included 27 critically ill patients (15 males) of mean age 49.9 ± 4.3 years and illness severity of APACHE II score 15.0 ± 1.7, SAPS II 32.4 ± 3.7, and SOFA score 6.0 ± 0.5. Daily costs of initial empiric antibiotic therapy were significantly higher compared with those of the therapy guided according to susceptibility results in confirmed bacteremias. This was applicable for Gram-positive (€61.0 ± 12.7 vs €130.4 ± 56.3, P = 0.009), Gram-negative (€181.0 ± 47.8 vs €142.7 ± 42.9, P = 0.0063) and mixed (€166.0 ± 21.1 vs €96.0 ± 34.0, P = 0.0016) bacteremias. In patients with other sites of infection the antibiotic costs did not differ (P = 0.112) between therapy guided according to susceptibility results compared with empiric therapy (€239.0 ± 49.7 vs €242.0 ± 88.7).

In patients with negative cultures the daily antibiotic cost was €110.7 ± 31.9. Therapy in those patients was discontinued earlier and they had a significantly lower length of ICU stay (P = 0.000, 8.7 ± 0.9 days vs 24.6 ± 4.1 days).

Conclusion

According to our bacteriologic susceptibility results, the de-escalation therapy is applicable only in bacteremias which may lead to decreased antibiotic costs. Such an approach is not applicable in infections of other sites possibly due to multidrug resistance pathogens.