Background: A drawback of vancomycin use is the need for therapeutic drug monitoring and renal function monitoring. Traditional blood sampling involves drawing blood through a venepuncture. An alternative method, dried blood spot (DBS) sampling allows for self-sampling at home. Objectives: To clinically validate a DBS method for simultaneous monitoring of vancomycin and creatinine. Methods: Hospitalized adults treated with intravenous vancomycin were included (trial registration NCT05257070). Blood sampling consisted of one venepuncture and one finger prick. Whole-blood DBS samples from patients were obtained by applying one drop of whole blood onto Whatman 903 filtrate paper. Bland–Altman analyses were used to assess the agreement and bias between the two measurements. Patients were asked to state their preferences for one of the two sampling methods. Results: The study involved a final analysis of 39 patient samples for the clinical validation of vancomycin and 46 patient samples for the clinical validation of creatinine. The difference between plasma and DBS concentrations was ≤20% for 77% of the vancomycin samples, the mean bias was −0.1379% (95% limit of agreement −5.899–5.623). The difference between plasma and DBS concentrations was ≤20% for 89% of the creatinine samples, the mean bias was 2.656% (95% limit of agreement −26.16–31.47). Most patients (18 out of 31) preferred a finger prick over a venepuncture and 12 patients indicated no preference. Conclusions: This is the first study that successfully clinically validated a DBS sampling method for simultaneous measurement of vancomycin and creatinine, allowing for direct use in (outpatient) practice.

Background: Intentional sodium nitrite poisoning is an emerging trend worldwide, as it is promoted for its use in self-euthanasia. Nitrite dipstick urinalysis could potentially serve as a rapid-diagnostic tool. Urine dipstick analysis is a common point-of-care test (POCT) for the initial diagnosis of urinary tract infections. The aim of this study was to investigate nitrite dipstick urinalysis as a potential reliable POCT for the early detection of sodium nitrate poisoning. Methods: Postmortem urine samples, collected over 1 year, were prospectively analyzed for nitrite presence using a urine dipstick method. In addition, a retrospective search was conducted in the database to identify cases with suspected or confirmed sodium nitrite poisoning as the cause of death. Available urine samples from these cases were screened for the presence of nitrite. Results: Prospectively, 10 of the 420 urine samples tested positive for nitrite presence: 6 samples without any suspicion of sodium nitrite ingestion and 4 with confirmed sodium nitrite poisoning as the cause of death. In addition, in our retrospective study, 12 cases of suspected sodium nitrite poisoning were tested for nitrite presence in the urine using the dipstick. Of these, 8 tested positive for nitrite. Two of the 12 cases were later attributed to intoxication with other substances. As a control, urine samples spiked with sodium nitrite were tested using the dipstick; the pink color intensified with increasing sodium nitrite concentration. Conclusions: Nitrite dipstick urinalysis is a feasible approach for the early detection of nitrite poisoning in postmortem toxicological screening. In addition, this rapid POCT shows potential as a diagnostic tool for use in acute clinical settings in cases of suspected sodium nitrite poisoning or elevated methemoglobinemia with an unknown cause.

Introduction: Vancomycin is a widely used antibiotic in Outpatient Parenteral Antimicrobial Therapy (OPAT) services. The objective of this systematic review was to evaluate the published literature on the efficacy and safety outcomes of outpatient vancomycin therapy. Methods: A systematic search was performed in Embase, Medline ALL, the Web of Science Core Collection, and the Cochrane Central Register of Controlled Trials from database inception until 20 March 2026. Both randomized controlled trials and non-randomized studies published in peer-reviewed journals were included. Study quality was assessed using the Newcastle–Ottawa Scale. Results: A total of 75 studies were included. Clinical success rates of 40.9% to 100% were reported. Reported adverse event (AE) rates ranged widely from 5.7% to 85.7%. Comparative studies suggest a higher risk of nephrotoxicity during intermittent infusion compared to continuous infusion. Reported line-related AE ranged from 1.1% to 5.7% and readmission risks associated with vancomycin use were inconsistent across studies. Conclusions: This systematic review shows that vancomycin is an effective agent to use in OPAT setting, however its use is associated with a risk of adverse events. The findings of this study underscore the need for a dedicated multidisciplinary OPAT team to ensure proper follow-up and tailored vancomycin management in the outpatient setting.