A Targeted LC-MRM3 Proteomic Approach for the Diagnosis of SARS-CoV-2 Infection in Nasopharyngeal Swabs.

Since its first appearance, severe acute respiratory syndrome coronavirus 2 quickly spread around the world and the lack of adequate PCR testing capacities, especially during the early pandemic, led the scientific community to explore new approaches such as mass spectrometry (MS). We developed a proteomics workflow to target several tryptic peptides of the nucleocapsid protein. A highly selective multiple reaction monitoring-cubed (MRM3) strategy provided a sensitivity increase in comparison to conventional MRM acquisition. Our MRM3 approach was first tested on an Amsterdam public health cohort (alpha-variant, 760 participants) detecting viral nucleocapsid protein peptides from nasopharyngeal swabs samples presenting a cycle threshold value down to 35 with sensitivity and specificity of 94.2% and 100.0%, without immunopurification. A second iteration of the MS-diagnostic test, able to analyze more than 400 samples per day, was clinically validated on a Leiden-Rijswijk public health cohort (delta-variant, 2536 participants) achieving 99.9% specificity and 93.1% sensitivity for patients with cycle threshold values up to 35. In this manuscript, we also developed and brought the first proof of the concept of viral variant monitoring in a complex matrix using targeted MS.

Clinical sub-phenotypes of Staphylococcus aureus bacteraemia.

BACKGROUND: Staphylococcus aureus bacteraemia (SAB) is a clinically heterogeneous disease. The ability to identify sub-groups of patients with shared traits (sub-phenotypes) is an unmet need that could allow patient stratification for clinical management and research. We aimed to test the hypothesis that clinically-relevant sub-phenotypes can be reproducibly identified amongst patients with SAB. METHODS: We studied three cohorts of hospitalised adults with monomicrobial SAB: a UK retrospective observational study (Edinburgh cohort, n=458), the UK ARREST randomised trial (n=758), and the Spanish SAFO randomised trial (n=214). Latent class analysis was used to identify sub-phenotypes using routinely-collected clinical data, without considering outcomes. Mortality and microbiologic outcomes were then compared between sub-phenotypes. RESULTS: Included patients had predominantly methicillin-susceptible SAB (1366/1430,95.5%). We identified five distinct, reproducible clinical sub-phenotypes: (A) SAB associated with older age and comorbidity, (B) nosocomial intravenous catheter-associated SAB in younger people without comorbidity, (C) community-acquired metastatic SAB, (D) SAB associated with chronic kidney disease, and (E) SAB associated with injection drug use. Survival and microbiologic outcomes differed between the sub-phenotypes. 84-day mortality was highest in sub-phenotype A, and lowest in B and E. Microbiologic outcomes were worse in sub-phenotype C. In a secondary analysis of the ARREST trial, adjunctive rifampicin was associated with increased 84-day mortality in sub-phenotype B and improved microbiologic outcomes in sub-phenotype C. CONCLUSIONS: We have identified reproducible and clinically-relevant sub-phenotypes within SAB, and provide proof-of-principle of differential treatment effects. Through clinical trial enrichment and patient stratification, these sub-phenotypes could contribute to a personalised medicine approach to SAB.

Use of proxy indicators for automated surveillance of severe acute respiratory infection, the Netherlands, 2017 to 2023: a proof-of-concept study.

BackgroundEffective pandemic preparedness requires robust severe acute respiratory infection (SARI) surveillance. However, identifying SARI patients based on symptoms is time-consuming. Using the number of reverse transcription (RT)-PCR tests or contact and droplet precaution labels as a proxy for SARI could accurately reflect the epidemiology of patients presenting with SARI.AimWe aimed to compare the number of RT-PCR tests, contact and droplet precaution labels and SARI-related International Classification of Disease (ICD)-10 codes and evaluate their use as surveillance indicators.MethodsPatients from all age groups hospitalised at Leiden University Medical Center between 1 January 2017 up to and including 30 April 2023 were eligible for inclusion. We used a clinical data collection tool to extract data from electronic medical records. For each surveillance indicator, we plotted the absolute count for each week, the incidence proportion per week and the correlation between the three surveillance indicators.ResultsWe included 117,404 hospital admissions. The three surveillance indicators generally followed a similar pattern before and during the COVID-19 pandemic. The correlation was highest between contact and droplet precaution labels and ICD-10 diagnostic codes (Pearson correlation coefficient: 0.84). There was a strong increase in the number of RT-PCR tests after the start of the COVID-19 pandemic.DiscussionAll three surveillance indicators have advantages and disadvantages. ICD-10 diagnostic codes are suitable but are subject to reporting delays. Contact and droplet precaution labels are a feasible option for automated SARI surveillance, since these reflect trends in SARI incidence and may be available real-time.

Patients' Perspectives and Feasibility of Home Monitoring in Acute Care: The AcuteCare@Home Flash Mob Study.

Objective: To determine patients' perspectives on home monitoring at emergency department (ED) presentation and shortly after admission and compare these with their physicians' perspectives. Methods: Forty Dutch hospitals participated in this prospective flash mob study. Adult patients with acute medical conditions, treated by internal medicine specialties, presenting at the ED or admitted at the admission ward within the previous 24 h were included. The primary outcome was the proportion of patients who were able and willing to undergo home monitoring. Secondary outcomes included identifying barriers to home monitoring, patient's prerequisites, and assessing the agreement between the perspectives of patients and treating physicians. Results: On February 2, 2023, in total 665 patients [median age 69 (interquartile range: 55-78) years; 95.5% community dwelling; 29.3% Modified Early Warning Score ≥3; 29.5% clinical frailty score ≥5] were included. In total, 19.6% of ED patients were admitted and 26% of ward patients preferred home monitoring as continuation of care. Guaranteed readmission (87.8%), ability to contact the hospital 24/7 (77.3%), and a family caregiver at home (55.7%) were the most often reported prerequisites. Barriers for home monitoring were feeling too severely ill (78.8%) and inability to receive the required treatment at home (64.4%). The agreement between patients and physicians was fair (Cohens kappa coefficient 0.26). Conclusions: A substantial proportion of acutely ill patients stated that they were willing and able to be monitored at home. Guaranteed readmission, availability of a treatment team (24/7), and a home support system are needed for successful implementation of home monitoring in acute care.

Viral clearance, pharmacokinetics and tolerability of ensovibep in patients with mild to moderate COVID-19: A phase 2a, open-label, single-dose escalation study.

AIM: To assess viral clearance, pharmacokinetics, tolerability and symptom evolution following ensovibep administration in symptomatic COVID-19 outpatients. METHODS: In this open-label, first-in-patient study a single dose of either 225 mg (n = 6) or 600 mg (n = 6) of ensovibep was administered intravenously in outpatients with mild-to-moderate COVID-19 symptoms. Pharmacokinetic profiles were determined (90-day period). Pharmacodynamic assessments consisted of viral load (qPCR and cultures) and symptom questionnaires. Immunogenicity against ensovibep and SARS-CoV-2-neutralizing activity were determined. Safety and tolerability were assessed throughout a 13-week follow-up. RESULTS: Both doses showed similar pharmacokinetics (first-order) with mean half-lives of 14 (SD 5.0) and 13 days (SD 5.7) for the 225- and 600-mg groups, respectively. Pharmacologically relevant serum concentrations were maintained in all subjects for at least 2 weeks postdose, regardless of possible immunogenicity against ensovibep. Viral load changes from baseline at day 15 were 5.1 (SD 0.86) and 5.3 (SD 2.2) log10 copies/mL for the 225- and 600-mg doses, respectively. COVID-19 symptom scores decreased from 10.0 (SD 4.1) and 11.3 (SD 4.0) to 1.6 (SD 3.1) and 3.3 (SD 2.4) in the first week for the 225- and 600-mg groups, respectively. No anti-SARS-CoV-2 neutralizing activity was present predose and all patients had SARS-CoV-2 antibodies at day 91. Adverse events were of mild-to-moderate severity, transient and self-limiting. CONCLUSION: Single-dose intravenous administration of 225 or 600 mg of ensovibep appeared safe and well tolerated in patients with mild-to-moderate COVID-19. Ensovibep showed favourable pharmacokinetics in patients and the pharmacodynamic results warrant further research in a larger phase 2/3 randomized-controlled trail.

Non-lytic antibiotic treatment in community-acquired pneumococcal pneumonia does not attenuate inflammation: the PRISTINE trial.

BACKGROUND: The inflammatory response in pneumococcal infection is primarily driven by immunoreactive bacterial cell wall components [lipoteichoic acid (LTA)]. An acute release of these components occurs when pneumococcal infection is treated with ß-lactam antibiotics. OBJECTIVES: We hypothesized that non-lytic rifampicin compared with lytic ß-lactam antibiotic treatment would attenuate the inflammatory response in patients with pneumococcal pneumonia. METHODS: In the PRISTINE (Pneumonia treated with RIfampicin aTtenuates INflammation) trial, a randomized, therapeutic controlled, exploratory study in patients with community-acquired pneumococcal pneumonia, we looked at LTA release and inflammatory and clinical response during treatment with both rifampicin and ß-lactam compared with treatment with ß-lactam antibiotics only. The trial is registered in the Dutch trial registry, number NTR3751 (European Clinical Trials Database number 2012-003067-22). RESULTS: Forty-one patients with community-acquired pneumonia were included; 17 of them had pneumococcal pneumonia. LTA release, LTA-mediated inflammatory responses, clinical outcomes, inflammatory biomarkers and transcription profiles were not different between treatment groups. CONCLUSIONS: The PRISTINE study demonstrated the feasibility of adding rifampicin to ß-lactam antibiotics in the treatment of community-acquired pneumococcal pneumonia, but, despite solid in vitro and experimental animal research evidence, failed to demonstrate a difference in plasma LTA concentrations and subsequent inflammatory and clinical responses. Most likely, an inhibitory effect of human plasma contributes to the low immune response in these patients. In addition, LTA plasma concentration could be too low to mount a response via Toll-like receptor 2 in vitro, but may nonetheless have an effect in vivo.

Clinical implications of rapid ePlex® Respiratory Pathogen Panel testing compared to laboratory-developed real-time PCR.

Rapid diagnosis of respiratory infections is of great importance for adequate isolation and treatment. Due to the batch-wise testing, laboratory-developed real-time polymerase chain reaction (PCR) assays (LDT) often result in a time to result of one day. Here, LDT was compared with rapid ePlex® Respiratory Pathogen (RP) Panel testing of GenMark Diagnostics (Carlsbad, CA, USA) with regard to time to result, installed isolation precautions, and antibacterial/antiviral treatment. Between January and March 2017, 68 specimens of 64 patients suspected of an acute respiratory infection were tested with LDT and the ePlex® RP panel. The time to result was calculated as the time between sample reception and result reporting. Information regarding isolation and antibacterial/antiviral treatment was obtained from the patient records. Thirty specimens tested LDT positive (47%) and 29 ePlex® RP panel positive (45%). The median time to result was 27.1 h (range 6.5-96.6) for LDT versus 3.4 h (range 1.5-23.6) for the RP panel, p-value < 0.001. In 14 out of 30 patients, isolation was discontinued based on the ePlex® RP panel results, saving 21 isolation days. ePlex® RP panel test results were available approximately one day ahead of the LDT results in the 19 patients receiving antiviral/antibacterial treatment. In addition, two bacterial pathogens, not requested by the physician, were detected using the RP panel. Analysis of respiratory infections with the ePlex® RP panel resulted in a significant decrease in time to result, enabling a reduction in isolation days in half of the patients. Furthermore, syndromic RP panel testing increased the identification of causative pathogens.

Flucloxacillin Results in Suboptimal Plasma Voriconazole Concentrations.

Combining voriconazole and flucloxacillin is indicated in patient cohorts experiencing both invasive aspergillosis and Gram-positive infections (e.g., patients with chronic granulomatous disease or postinfluenza pulmonary aspergillosis). We report a highly relevant interaction between voriconazole and flucloxacillin, resulting in subtherapeutic plasma voriconazole concentrations in more than 50% of patients, that poses a severe threat if not managed properly.

ICARES: a real-time automated detection tool for clusters of infectious diseases in the Netherlands.

BACKGROUND: Clusters of infectious diseases are frequently detected late. Real-time, detailed information about an evolving cluster and possible associated conditions is essential for local policy makers, travelers planning to visit the area, and the local population. This is currently illustrated in the Zika virus outbreak. METHODS: In the Netherlands, ICARES (Integrated Crisis Alert and Response System) has been developed and tested on three syndromes as an automated, real-time tool for early detection of clusters of infectious diseases. From local general practices, General Practice Out-of-Hours services and a hospital, the numbers of routinely used syndrome codes for three piloted tracts i.e., respiratory tract infection, hepatitis and encephalitis/meningitis, are sent on a daily basis to a central unit of infectious disease control. Historic data combined with information about patients' syndromes, age cohort, gender and postal code area have been used to detect clusters of cases. RESULTS: During the first 2 years, two out of eight alerts appeared to be a real cluster. The first was part of the seasonal increase in Enterovirus encephalitis and the second was a remarkably long lasting influenza season with high peak incidence. CONCLUSIONS: This tool is believed to be the first flexible automated, real-time cluster detection system for infectious diseases, based on physician information from both general practitioners and hospitals. ICARES is able to detect and follow small regional clusters in real time and can handle any diseases entity that is regularly registered by first line physicians. Its value will be improved when more health care institutions agree to link up with ICARES thus improving further the signal-to-noise ratio.

[Prehospital triage of undifferentiated syndromes in the ambulance]. / Prehospitale triage op basis van onduidelijke symptomen.

Increasing complexity due to an ageing population, a shortage of healthcare professionals and the rising costs are major concerns for the acute care in the coming years. Innovative triage methods in the ambulance could improve appropriate care for patients with subacute undifferentiated syndromes. A proportion of these patients should not be transferred to an emergency department. We conducted a systematic literature search on prehospital triage in the ambulance and evaluated the results relevant to the Dutch acute care system. Consultation of primary care or hospital physicians by paramedics to decide on the optimal strategy for the individual patient seems promising. Adding a video connection could increase the potential benefits. Point-of-care testing in well-defined syndromes does improve prehospital triage and may therefore be of benefit in undifferentiated syndromes. Both techniques may keep ambulances away from presenting specific patients on emergency departments, enabling appropriate use of scarce acute care facilities.

Influenza Season and Outcome After Elective Cardiac Surgery: An Observational Cohort Study.

BACKGROUND: An asymptomatic respiratory viral infection during cardiac surgery could lead to pulmonary complications and increased mortality. For elective surgery, testing for respiratory viral infection before surgery or vaccination could reduce the number of these pulmonary complications. The aim of this study was to investigate the association between influenzalike illness (ILI) seasons and prolonged mechanical ventilation and inhospital mortality in a Dutch cohort of adult elective cardiac surgery patients. METHODS: Cardiac surgery patients who were admitted to the intensive care unit between January 1, 2014, and February 1, 2020, were included. The primary endpoint was the duration of invasive mechanical ventilation in the ILI season compared with baseline season. Secondary endpoints were the median Pao2 to fraction of inspired oxygen ratio on days 1, 3, and 7 and postoperative inhospital mortality. RESULTS: A total of 42,277 patients underwent cardiac surgery, 12,994 (30.7%) in the ILI season, 15,843 (37.5%) in the intermediate season, and 13,440 (31.8%) in the baseline season. No hazard rates indicative of a longer duration of invasive mechanical ventilation during the ILI season were found. No differences were found for the median Pao2 to fraction of inspired oxygen ratio between seasons. However, inhospital mortality was higher in the ILI season compared with baseline season (odds ratio 1.67; 95% CI, 1.14-2.46). CONCLUSIONS: Patients undergoing cardiac surgery during the ILI season were at increased risk of inhospital mortality compared with patients in the baseline season. No evidence was found that this difference is caused by direct postoperative pulmonary complications.

[Influenza vaccination as secondary prevention for cardiovascular disease]. / Influenzavaccinatie bij hartpatiënten voorkomt cardiale complicaties.

Influenza infection increases the risk of cardiovascular complications and mortality in patients with heart disease. In patients with coronary artery disease influenza vaccination has been shown to reduce cardiovascular mortality, but high-quality evidence was missing. New trial data from a RCT in patients shortly after myocardial infarction has confirmed the significant reduction of the risk of major adverse cardiovascular events (MACE) and cardiovascular death after influenza vaccination. Also in patients with heart failure the first published RCT in heart failure shows a clinical benefit of influenza vaccination versus placebo during the influenza season, confirming preceding observational studies. Meta-analyses from the study data estimate that after influenza vaccination a risk reduction of MACE of at least 25% is possible in patients with heart disease. The current underutilization of influenza vaccines in heart patients should be addressed because influenza vaccination has proven to be an effective and safe instrument for secondary prevention.

A comparison of the effectiveness of different doses of tocilizumab and sarilumab in the treatment of severe COVID-19: a natural experiment due to drug shortages.

OBJECTIVES: Interleukin (IL)-6 inhibitors are administered to treat patients hospitalized with COVID-19. In 2021, due to shortages, different dosing regimens of tocilizumab, and a switch to sarilumab, were consecutively implemented. Using real-world data, we compare the effectiveness of these IL-6 inhibitors. METHODS: Hospitalized patients with COVID-19, treated with IL-6 inhibitors, were included in this natural experiment study. Sixty-day survival, hospital- and intensive care unit (ICU) length of stay, and progression to ICU or death were compared between 8 mg/kg tocilizumab, fixed-dose tocilizumab, low-dose tocilizumab, and fixed-dose sarilumab treatment groups. RESULTS: A total of 5485 patients from 49 hospitals were included. After correction for confounding, increased hazard ratios (HRs) for 60-day mortality were observed for fixed-dose tocilizumab (HR 1.20, 95% confidence interval [CI] 1.04-1.39), low-dose tocilizumab (HR 1.12, 95% CI 0.97-1.31), and sarilumab (HR 1.24, 95% CI 1.08-1.42), all relative to 8 mg/kg. The 8 mg/kg dosing regimen had lower odds of progression to ICU or death. Both hospital- and ICU length of stay were shorter for low-dose tocilizumab than for the 8 mg/kg group. CONCLUSION: We found differences in the probability of 60-day survival and the incidence of the combined outcome of mortality or ICU admission, mostly favoring 8 mg/kg tocilizumab. Because of potential time-associated residual confounding, further clinical studies are warranted.

Evaluation of pragmatic oxygenation measurement as a proxy for Covid-19 severity.

Choosing optimal outcome measures maximizes statistical power, accelerates discovery and improves reliability in early-phase trials. We devised and evaluated a modification to a pragmatic measure of oxygenation function, the [Formula: see text] ratio. Because of the ceiling effect in oxyhaemoglobin saturation, [Formula: see text] ratio ceases to reflect pulmonary oxygenation function at high [Formula: see text] values. We found that the correlation of [Formula: see text] with the reference standard ([Formula: see text]/[Formula: see text] ratio) improves substantially when excluding [Formula: see text] and refer to this measure as [Formula: see text]. Using observational data from 39,765 hospitalised COVID-19 patients, we demonstrate that [Formula: see text] is predictive of mortality, and compare the sample sizes required for trials using four different outcome measures. We show that a significant difference in outcome could be detected with the smallest sample size using [Formula: see text]. We demonstrate that [Formula: see text] is an effective intermediate outcome measure in COVID-19. It is a non-invasive measurement, representative of disease severity and provides greater statistical power.

COVID-box Experiences of Patients and Health Care Professionals (COVID-box Project): Single-Center, Retrospective, Observational Study.

BACKGROUND: During the COVID-19 pandemic, several home monitoring programs have described the success of reducing hospital admissions, but only a few studies have investigated the experiences of patients and health care professionals. OBJECTIVE: The objective of our study was to determine patients' and health care professionals' experiences and satisfaction with employing the COVID-box. METHODS: In this single-center, retrospective, observational study, patients and health care professionals were asked to anonymously fill out multiple-choice questionnaires with questions on a 5-point or 10-point Likert scale. The themes addressed by patients were the sense of reassurance and safety, experiences with teleconsultations, their appreciation for staying at home, and the instructions for using the COVID-box. The themes addressed by health care professionals who treated patients with the COVID-box were the characteristics of the COVID-box, the technical support service and general satisfaction, and their expectations and support for this telemonitoring concept. Scores were interpreted as insufficient (≤2 or ≤5, respectively), sufficient (3 or 6-7, respectively), or good (≥4 or ≥8, respectively) on a 5-point or 10-point Likert scale. RESULTS: A total of 117 patients and 25 health care professionals filled out the questionnaires. The median score was 4 (IQR 4-5) for the sense of safety, the appreciation for staying at home, and experiences with teleconsultations, with good scores from 76.5% (88/115), 86% (56/65), and 83.6% (92/110) of the patients, respectively. Further, 74.4% (87/117) of the patients scored the home monitoring program with a score of ≥8. Health care professionals scored the COVID-box with a minimum median score of 7 (IQR 7-10) on a 10-point scale for all domains (ie, the characteristics of the COVID-box and the technical support service and general satisfaction). For the sense of safety, user-friendliness, and additional value of the COVID-box, the median scores were 8 (IQR 8-10), 8 (IQR 7-9), and 10 (IQR 8-10), respectively, with good scores from 86% (19/22), 75% (15/20), and 96% (24/25) of the health care professionals, respectively. All health care professionals (25/25, 100%) gave a score of ≥8 for supporting this home monitoring concept, with a median score of 10 (IQR 10-10). CONCLUSIONS: The positive experiences and satisfaction of involved users are key factors for the successful implementation of a novel eHealth solution. In our study, patients, as well as health care professionals, were highly satisfied with the use of the home monitoring program-the COVID-box project. Remote home monitoring may be an effective approach in cases of increased demand for hospital care and high pressure on health care systems.