SiM20 Posters

19 Sensors in Medicine 2020 Results Vancomycin was detected in five out of five sweat samples for the first time. The amount of previously applied doses varied from 1x-36x. Vancomycin concentrations ranged from 0.011 – 0.118mg/L in sweat and from 4.7 – 8.5mg/L in blood (Table 1). Table 1. Patient characteristics and antibiotic concentrations, GFR indicates glomerular filtration rate. Discussion Our results serve as a proof-of-concept that vancomycin is detectable in eccrine sweat. If combined with on-skin smartphone-based biosensors coupled to analytical applications, antibiotic concentrations in sweat might enable a first point of care, lab-independent and non-invasive therapeutic drug monitoring in skin and soft tissue infections.(4) References: 1. WHO. Global action plan on antimicrobial resistance 2015. | 2. Ray A, Malin D, Nicolau DP, Wiskirchen DE. Antibiotic Tissue Penetration in Diabetic Foot Infections A Review of the Microdialysis Literature and Needs for Future Research. Journal of the American Podiatric Medical Association. 2015;105(6):520-31. | 3. Stein GE, Wells EM. The importance of tissue penetration in achieving successful antimicrobial treatment of nosocomial pneumonia and complicated skin and soft-tissue infections caused by methicillin-resistant Staphylococcus aureus: vancomycin and linezolid. Current Medical Research and Opinion. 2010;26(3):571-88. | 4. Brasier N, Eckstein J. Sweat as a Source of Next-Generation Digital Biomarkers. Digital Biomarkers. 2019;3(3):155-65. Patient 1 2 3 4 5 Age (years) 68 63 77 67 66 Gender (F/M) F M F M M Body Weight (kg) 57.7 130.0 97.5 82.7 72.0 GFR (ml/min/1.73m^2) 94 70 86 59 43 Vancomycin: - per dose (mg) 1000 1000 750 500 750 - per day (mg) 1500 2000 1500 1000 750 - amount of previous doses (n) 1 36 4 5 12 Vancomycin in sweat (mg/L) 0.011 0.118 0.016 0.032 0.019 Vancomycin in blood (mg/L) 5.8 4.7 5.6 5.2 8.5 No conflicts of interest to declare in regard to this project. | The project was funded by an Innovation Pilot Project Grant, University Basel, Switzerland | Corresponding author: Noé Brasier, MD, email: noe.brasier@usb.ch Take home messages: - Serum and tissue concentrations combined with minimal inhibitory concentration are key issues to guide optimal antibiotic therapy - Currently, no point of care laboratory technique is available to measure tissue concentrations - Proof of concept was achieved with this study using vancomycin - Combined with smart biosensors, this may provide a first non-invasive, lab- independent antibiotic monitoring at the spot of need