Impact of therapeutic drug monitoring of antibiotics in the management of infective endocarditis.

Treatment of infective endocarditis (IE) is based on high doses of antibiotics with a prolonged duration. Therapeutic drug monitoring (TDM) allows antibiotic prescription optimization and leads to a personalized medicine, but no study evaluates its interest in the management of IE. We conducted a retrospective, bicentric, descriptive study, from January 2007 to December 2019. We included patients cared for IE, defined according to Duke's criteria, for whom a TDM was requested. Clinical and microbiological data were collected after patients' charts review. We considered a trough or steady-state concentration target of 20 to 50 mg/L. We included 322 IE episodes, corresponding to 306 patients, with 78.6% (253/326) were considered definite according to Duke's criteria. Native valves were involved in 60.5% (185/306) with aortic valve in 46.6% (150/322) and mitral in 36.3% (117/322). Echocardiography was positive in 76.7% (247/322) of cases. After TDM, a dosage modification was performed in 51.5% (166/322) (decrease in 84.3% (140/166)). After initial dosage, 46.3% (82/177) and 92.8% (52/56) were considered overdosed, when amoxicillin and cloxacillin were used, respectively. The length of hospital stay was higher for patient overdosed (25 days versus 20 days (p = 0.04)), and altered creatinine clearance was associated with overdosage (p = 0.01). Our study suggests that the use of current guidelines probably leads to unnecessarily high concentrations in most patients. TDM benefits predominate in patients with altered renal function, but probably limit adverse effects related to overdosing in most patients.

Harnessing the wisdom of crowds can improve guideline compliance of antibiotic prescribers and support antimicrobial stewardship.

Antibiotic overprescribing is a global challenge contributing to rising levels of antibiotic resistance and mortality. We test a novel approach to antibiotic stewardship. Capitalising on the concept of "wisdom of crowds", which states that a group's collective judgement often outperforms the average individual, we test whether pooling treatment durations recommended by different prescribers can improve antibiotic prescribing. Using international survey data from 787 expert antibiotic prescribers, we run computer simulations to test the performance of the wisdom of crowds by comparing three data aggregation rules across different clinical cases and group sizes. We also identify patterns of prescribing bias in recommendations about antibiotic treatment durations to quantify current levels of overprescribing. Our results suggest that pooling the treatment recommendations (using the median) could improve guideline compliance in groups of three or more prescribers. Implications for antibiotic stewardship and the general improvement of medical decision making are discussed. Clinical applicability is likely to be greatest in the context of hospital ward rounds and larger, multidisciplinary team meetings, where complex patient cases are discussed and existing guidelines provide limited guidance.

Impact of the French Infectious Diseases Society's (SPILF) proposals for shorter antibiotic therapies.

OBJECTIVE: To compare the practices of French infection specialists related to antibiotic therapy duration between 2016 and 2018. METHODS: We conducted two identical surveys (in 2016 and 2018) targeting hospital-based infection specialists (medical physicians, pharmacists) who gave at least weekly advice on antibiotic prescriptions. The questionnaire included 15 clinical vignettes. Part A asked about the durations of antibiotic therapies they would usually advise to prescribers, and part B asked about the shortest duration they would be willing to advise for the same clinical situations. RESULTS: We included 325 specialists (165 in 2016 and 160 in 2018), mostly infectious disease specialists (82.4%, 268/325), members of antibiotic stewardship teams in 72% (234/325) of cases. Shorter antibiotic treatments (as compared with the literature) were advised to prescribers in more than half of the vignettes by 71% (105/147) of respondents in 2018, versus 46% (69/150) in 2016 (P<0.001). Guidelines used by participants displayed fixed durations for 77% (123/160) of cases in 2018 versus 21% (35/165) in 2016. Almost all respondents (89%, 131/160) declared they were aware of the 2017 SPILF's proposal. CONCLUSION: The release of guidelines promoting shorter durations of antibiotic therapy seems to have had a favourable impact on practices of specialists giving advice on antibiotic prescriptions.