Population pharmacokinetics of vancomycin in patients with diabetic foot infection: a comparison of five models.

Purpose: This study aimed to compare individual pharmacokinetic (PK) parameters of vancomycin with predicted values from five population PK models in patients with diabetic foot infections (DFIs). Methods: Patients with a diagnosis of DFI and an estimated glomerular filtration rate (eGFR) ≥ 30 mL/min were included in the study. Individual PK data was carried on by collecting three vancomycin serum concentrations in a steady-state condition. Five published population-based nomograms were assumed to predict PK parameters. Optimal vancomycin exposure was considered as a trough level of 15-20 mg/L or the area under the curve over 24 h/minimum inhibitory concentration (AUC24/MIC) ≥ 400. Results: A total of 48 samples from 16 patients were analyzed. There was a statistically significant difference between the volume of distribution (Vd) obtained from population methods and the individual estimations (P ≤ 0.001 in Ambrose and Burton, P = 0.010 and 0.006 in Bauer and Burton revised models, respectively). AUC/MIC ≥ 400 was achieved in 68.7% of patients while 50% had a trough level of less than 15 mg/L. Conclusions: Vancomycin PK parameters, particularly individualized Vd, may not be predictable by population nomograms in patients with DFI and stable renal function. Moreover, the weak correlation between AUC24 values and trough concentrations underlines the starting practice of vancomycin AUC24-based monitoring and dosing in the clinical setting.

Respiratory Bacterial and Fungal Superinfections During the Third Surge of the COVID-19 Pandemic in Iran.

Objective: We characterized bacterial and fungal superinfection and evaluated the antimicrobial resistance profile against the most common superinfection-causing pathogens (Klebsiella pneumoniae, Acinetobacter baumannii, and Staphylococcus aureus). Methods: In a cross-sectional study, 192 respiratory samples were collected from patients with and without SARS-COV-2 admitted to a teaching hospital in Tehran. Superinfection proportions and the antibiotic resistance profile were assessed and compared with demographic, comorbidities, and other clinical factors. Results: Superinfection rate was 60% among COVID-19 patients (p = 0.629). Intensive care unit admission (p = 0.017), mortality rate (p ≤ 0.001), and antiviral and corticosteroid therapy (p ≤ 0.001) were significantly more common among patients with severe acute respiratory syndrome coronavirus 2 (SARS-COV-2). The most common superinfections were caused by K. pneumoniae (42.7%, 82/192), A. baumannii (14.6%, 28/192), and S. aureus (13%, 25/192). A. baumannii isolates exhibited greater antibiotic resistance. Forty-four percent (11/25) of S. aureus isolates were cefoxitin resistant and also confirmed as methicillin-resistant S. aureus by PCR. Conclusion: The rise of difficult-to-treat infections with a high burden of antibiotic resistance, coupled with an increase in mortality rate of SARS-COV-2 superinfected individuals, illustrates the impact of the COVID-19 pandemic on antimicrobial resistance. Post-pandemic antimicrobial resistance crisis management requires precise microbiological diagnosis, drug susceptibility testing, and prescription of antimicrobials appropriate for the patient's condition.

Case series of nebulizing r-tPA for COVID-19 induced acute respiratory distress syndrome.

Fibrin deposition in the alveolar spaces during pulmonary involvement of COVID-19 impairs the O2/CO2 exchange and leads to respiratory symptoms. In this report, Recombinant Tissue Plasminogen Activator (r-tPA) has been nebulized to 3 critically ill COVID-19 patients in order to resolve the deposited fibrin while avoiding the risk of bleeding. Based on these observations, nebulization of r-tPA may be a potential therapeutic approach and new area of research for future studies.

High-dose Intravenous Vitamin C in Early Stages of Severe Acute Respiratory Syndrome Coronavirus 2 Infection: A Double-blind, Randomized, Controlled Clinical Trial.

Objective: Based on previous studies in the sepsis population, Vitamin C could prevent injuries when administered in high doses and before the damage is established. This study aimed to evaluate the protective potentials of high-dose Vitamin C in the progression of coronavirus disease 2019 (COVID-19). Methods: A double-blind, placebo-controlled clinical trial was conducted. Patients with moderate-to-severe disease severity based on the World Health Organization definition were enrolled and received 12 g/d Vitamin C (high-dose intravenous Vitamin C [HDIVC]) or placebo for 4 days. Sequential Organ Failure Assessment (SOFA) score as a primary outcome, National Early Warning Score, Ordinal Scale of Clinical Improvement, and cytokine storm biomarkers were recorded on days 0, 3, and 5. Survival was also assessed on day 28 after enrollment. Findings: Seventy-four patients (37 patients in each group) were enrolled from April 5, 2020, to November 19, 2020, and all patients completed follow-up. A lower increase in SOFA score during the first 3 days of treatment (+0.026 vs. +0.204) and a higher decrease in this parameter in the last 2 days (-0.462 vs. -0.036) were observed in the treatment group. However, these differences did not reach a significance level (P = 0.57 and 0.12, respectively). Other indices of clinical and biological improvement, length of hospitalization, and intensive care unit admission days were the same between the two groups. Treatment did not affect the 28-day mortality. Conclusion: Among patients with moderate-to-severe disease of COVID-19, the use of HDIVC plus standard care resulted in no significant difference in SOFA score or 28-day mortality compared to the standard care alone.