In vitro assessment of genotoxic and cytotoxic effects of Artemisia annua L. tincture

The genus Artemisia (fam. Asteraceae) is one of the largest and widely distributed with around 500 species, majority used as aromatic and medicinal plants. Artemisia annua L. is widely used as a dietary spice, herbal tea, as a supplement, and in a non-pharmaceutical form for treatment of malaria and fever. It is orally consumed as capsules, extracts and tinctures and topically applied as an essential oil diluted in lotions and ointments. Artemisinin is the main constituent of Artemisia annua L. extracts. Since the discovery that the artemisinin is efficient in malaria treatment, there is also a growth in consumption of A. annua extracts for antitumour and even recently for antiviral treatments against SARS-CoV-2 infections. This study aimed to investigate genotoxic effect in peripheral blood culture and cytotoxic effects in cancer and normal cell lines, of commercially available A. annua L. tincture in series of dilutions. Both comet and neutral red uptake assays revealed dose-dependent genotoxicity and cytotoxicity of A. annua tincture dilutions. Comet assay revealed significantly increased DNA damage in peripheral blood cells while neutral-red assays showed increase in cytotoxicity (p<0.001) in both normal and cancer cell cultures treated with the lowest extract dilution compared to the highest one applied. Obtained results indicate caution needed in A. annua L. tincture use, especially when poorly diluted.

Distinct Subpopulations of Intravalvular Methicillin-Resistant Staphylococcus aureus with Variable Susceptibility to Daptomycin in Tricuspid Valve Endocarditis

ABSTRACT We present a case of endocarditis wherein organisms cultured from different valve leaflets yielded different daptomycin susceptibilities from each other and from organisms obtained from peripheral blood culture. Genomic analyses showed mutations in mprF, purR, and agrA. Pharmacokinetic simulations showed consistent activity of daptomycin plus beta-lactam against all subpopulations. This represents an opportunity to understand S. aureus evolution and fitness in vivo on daptomycin therapy and the role of beta-lactams to prevent the selection of daptomycin-resistant subpopulations.

1528. Rates of Peripheral Blood Culture Contamination in an Urban Children’s Hospital

Background Positive peripheral blood culture results are essential in guiding antimicrobial therapy in patients with bacteremia. However, false-positive results may frequently pose diagnostic issues in interpreting the test. These results can lead to increased costs and patient harm through the administration of unnecessary antibiotics and prolongation of hospital stay. The maximum acceptable contamination rate for peripheral blood cultures as suggested by the College of American Pathologists is 3%. Methods We initiated a longitudinal quality improvement project to monitor peripheral blood contamination rates at our children’s hospital in Brooklyn, NY. We reviewed positive blood culture results on a monthly basis and assessed whether they represented true infections vs. contamination based on review of patient charts. Residents and nurses in the pediatric emergency department (ED), neonatal intensive care unit (NICU), pediatric intensive care unit (PICU), inpatient unit, and newborn nursery were educated on proper skin sterilization techniques using video demonstration; the importance of avoiding palpating the venipuncture site after sterilization and the importance of cleaning the port on the blood culture bottle were reinforced. Results The pediatric ED and the PICU had the highest contamination rates in 2018 at 4.38% and 3.82%, respectively. The newborn nursery had the lowest contamination rate, at 0%. The NICU and pediatric inpatient units had contamination rates that met the goal as well, at 1.25% and 0.72%, respectively. Conclusion The departments in need of targeted interventions are the pediatric ED and the PICU, both of which had contamination rates greater than the 3% goal rate set for our project. Future interventions currently being considered include re-education of nursing and resident staff as well as the creation of equipment bundles to facilitate adequate skin preparation prior to venipuncture. Disclosures All authors: No reported disclosures.

Cohort study protocol: Bioresource in Adult Infectious Diseases (BioAID)

Introduction: Infectious diseases have a major impact on morbidity and mortality in hospital. Microbial diagnosis remains elusive for most cases of suspected infection which impacts on the use of antibiotics. Rapid advances in genomic technologies combined with high-quality phenotypic data have great potential to improve the diagnosis, management and clinical outcomes of infectious diseases. The aim of the Bioresource in Adult Infectious Diseases (BioAID) is to provide a platform for biomarker discovery, trials and clinical service developments in the field of infectious diseases, by establishing a registry linking clinical phenotype to microbial and biological samples in adult patients who attend hospital with suspected infection. Methods and analysis: BioAID is a cohort study which employs deferred consent to obtain an additional 2.5mL RNA blood sample from patients who attend the Emergency Department (ED) with suspected infection when they undergo peripheral blood culture sampling. Clinical data and additional biological samples including DNA, serum and microbial isolates are obtained from BioAID participants during hospital admission. Participants are also asked to consent to be recalled for future studies. BioAID aims to recruit 10,000 patients from 5-8 sites across England. Since February 2014 >4000 individuals have been recruited to the study. The final cohort will be characterised using descriptive statistics including information on the number of cases that can be linked to biological and microbial samples to support future research studies. Ethical approval and section 251 exemption have been obtained for BioAID researchers to seek deferred consent from patients from whom a RNA specimen has been collected. Samples and meta-data obtained through BioAID will be made available to researchers worldwide following submission of an application form and research protocol. Conclusions: BioAID will support a range of study designs spanning discovery science, biomarker validation, disease pathogenesis and epidemiological analyses of clinical infection syndromes.

Blood Culture Contamination A Randomized Trial Evaluating the Comparative Effectiveness of 3 Skin Antiseptic Interventions

Objective.To determine relative rates of blood culture contamination for 3 skin antisepsis interventions—10% povidone iodine aqueous solution (PI), 2% iodine tincture (IT), and 2% Chlorhexidine gluconate in 70% isopropyl alcohol (CHG)—when used by dedicated phlebotomy teams to obtain peripheral blood cultures.Design.Randomized crossover trial with hospital floor as the unit of randomization.Setting.Teaching hospital with 885 beds.Patients.All adult patients undergoing peripheral blood culture collection on 3 medical-surgical floors from May 2009 through September 2009.Intervention.Each antisepsis intervention was used for 5 months on each study floor, with random crossover after a 1-month washout period. Phlebotomy teams collected all peripheral blood cultures. Each positive blood culture was adjudicated by physicians blinded to the intervention and scored as a true positive or contaminated blood culture. The primary outcome was the rate of blood culture contamination for each antisepsis agent.Results.In total, 12,904 peripheral blood culture sets were evaluated, of which 735 (5.7%) were positive. There were 98 contaminated cultures, representing 13.3% of all positive cultures. The overall blood culture contamination rate for the study population was 0.76%. Intent-to-treat rates of contaminated blood cultures were not significantly different among the 3 antiseptics (P = .18), yielding 0.58% with PI (95% confidence interval [CI], 0.38%-0.86%), 0.76% with IT (95% CI, 0.52%-1.07%), and 0.93% with CHG (95% CI, 0.67%-1.27%).Conclusion.Choice of antiseptic agent does not impact contamination rates when blood cultures are obtained by a phlebotomy team and should, therefore, be based on costs or preference.Trial Registration.ClinicalTrials.gov identifier: NCT01216761.