Percutaneous Auricular Vagus Nerve Stimulation Reduces Inflammation in Critical Covid-19 Patients.

Covid-19 is an infectious disease associated with cytokine storms and derailed sympatho-vagal balance leading to respiratory distress, hypoxemia and cardiovascular damage. We applied the auricular vagus nerve stimulation to modulate the parasympathetic nervous system, activate the associated anti-inflammatory pathways, and reestablish the abnormal sympatho-vagal balance. aVNS is performed percutaneously using miniature needle electrodes in ear regions innervated by the auricular vagus nerve. In terms of a randomized prospective study, chronic aVNS is started in critical, but not yet ventilated Covid-19 patients during their stay at the intensive care unit. The results show decreased pro-inflammatory parameters, e.g. a reduction of CRP levels by 32% after 1 day of aVNS and 80% over 7 days (from the mean 151.9 mg/dl to 31.5 mg/dl) or similarly a reduction of TNFalpha levels by 58.1% over 7 days (from a mean 19.3 pg/ml to 8.1 pg/ml) and coagulation parameters, e.g. reduction of DDIMER levels by 66% over 7 days (from a mean 4.5 µg/ml to 1.5 µg/ml) and increased anti-inflammatory parameters, e.g. an increase of IL-10 levels by 66% over 7 days (from the mean 2.7 pg/ml to 7 pg/ml) over the aVNS duration without collateral effects. aVNS proved to be a safe clinical procedure and could effectively supplement treatment of critical Covid-19 patients while preventing devastating over-inflammation.

Immunoglobulin G production in COVID-19 - associations with age, outcome, viral persistence, inflammation and pro-thrombotic markers.

Age represents the major risk factor for fatal disease outcome in coronavirus disease (COVID-19) due to age-related changes in immune responses. On the one hand lymphocyte counts continuously decline with advancing age, on the other hand somatic hyper-mutations of B-lymphocytes and levels of class-switched antibodies diminish, resulting in lower neutralizing antibody titers. To date the impact of age on immunoglobulin G (IgG) production in response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is unknown. Therefore, we investigated the impact of age on the onset of IgG production and its association with outcome, viral persistence, inflammatory and thrombotic markers in consecutive, hospitalized COVID-19 patients admitted to the Clinic Favoriten (Vienna, Austria) between April and October 2020 that fulfilled predefined inclusion criteria. Three different IgGs against SARS-CoV-2 (spike protein S1, nucleocapsid (NC), and the spike protein receptor binding domain (RBD)) were monitored in plasma of 97 patients upon admission and three times within the first week followed by weekly assessment during their entire hospital stay. We analyzed the association of clinical parameters including C-reactive protein (CRP), D-dimer levels and platelet count as well as viral persistence with the onset and concentration of different anti-SARS-CoV-2 specific IgGs. Our data demonstrate that in older individuals anti-SARS-CoV-2 IgG production increases earlier after symptom onset and that deceased patients have the highest amount of antibodies against SARS-CoV-2 whereas intensive care unit (ICU) survivors have the lowest titers. In addition, anti-SARS-CoV-2 IgG concentrations are not associated with curtailed viral infectivity, inflammatory or thrombotic markers, suggesting that not only serological memory but also other adaptive immune responses are involved in successful viral killing and protection against a severe COVID-19 infection.

The Role of Bacterial and Fungal Superinfection in Critical COVID-19.

BACKGROUND: The range of reported rates of bacterial and fungal superinfections in patients with a severe course of COVID-19 is wide, suggesting a lack of standardised reporting. METHODS: The rates of bacterial and fungal superinfection were assessed using predefined criteria to differentiate between infection and contamination. RESULTS: Overall, 117 patients admitted to the Intensive Care Unit due to severe COVID-19 were included. Overall, 55% of patients developed a superinfection and 13.6% developed a fungal superinfection (5.9% candidemia and 7.7% CAPA). The rate of ventilator-associated pneumonia was 65.2%. If superinfection was detected, the length of hospital stay was significantly longer and the mortality was especially increased if candidemia was detected. An increased risk of superinfection was observed in patients with pre-existing diabetes mellitus or chronic heart failure. The presence of immunomodulating therapy did not seem to have an impact on the frequency of superinfections. CONCLUSION: Increased awareness of high superinfection rates, fungal infections in particular, in patients suffering from severe COVID-19 is necessary.

Early administration of remdesivir may reduce mortality in hospitalized COVID-19 patients : A propensity score matched analysis.

BACKGROUND: Remdesivir is the only antiviral agent approved for the treatment of hospitalized coronavirus disease 2019 (COVID-19) patients requiring supplemental oxygen. Studies show conflicting results regarding its effect on mortality. METHODS: In this single center observational study, we included adult hospitalized COVID-19 patients. Patients who were treated with remdesivir were compared to controls. Remdesivir was administered for 5 days. To adjust for any imbalances in our cohort, a propensity score matched analysis was performed. The aim of our study was to analyze the effect of remdesivir on in-hospital mortality and length of stay (LOS). RESULTS: After propensity score matching, 350 patients (175 remdesivir, 175 controls) were included in our analysis. Overall, in-hospital mortality was not significantly different between groups remdesivir 5.7% [10/175] vs. control 8.6% [15/175], hazard ratio 0.50, 95% confidence interval (CI) 0.22-1.12, p = 0.091. Subgroup analysis showed a significant reduction of in-hospital mortality in patients who were treated with remdesivir ≤ 7 days of symptom onset remdesivir 4.2% [5/121] vs. control 10.4% [13/125], hazard ratio 0.26, 95% CI 0.09 to 0.75, p = 0.012 and in female patients remdesivir 2.9% [2/69] vs. control 12.2% [9/74], hazard ratio 0.18 95%CI 0.04 to 0.85, p = 0.03. Patients in the remdesivir group had a significantly longer LOS (11 days vs. 9 days, p = 0.046). CONCLUSION: Remdesivir did not reduce in-hospital mortality in our whole propensity score matched cohort, but subgroup analysis showed a significant mortality reduction in female patients and in patients treated within ≤ 7 days of symptom onset. Remdesivir may reduce mortality in patients who are treated in the early stages of illness.

Tocilizumab vs. baricitinib in hospitalized severe COVID-19 patients: results from a real-world cohort.

BACKGROUND: Tocilizumab and baricitinib are recommended treatment options for hospitalized COVID-19 patients requiring oxygen support. Literature about its efficacy and safety in a head-to-head comparison is scarce. METHODS: Hospitalized COVID-19 patients requiring oxygen were treated with tocilizumab or baricitinib additionally to dexamethasone. Tocilizumab was available from February till the 19th of September 2021 and baricitinib from 21st of September. The primary outcome was in-hospital mortality. Secondary outcome parameters were progression to mechanical ventilation (MV), length-of-stay (LOS) and potential side effects. RESULTS: 159 patients (tocilizumab 68, baricitinib 91) with a mean age of 60.5 years, 64% male were included in the study. Tocilizumab patients were admitted 1 day earlier, were in a higher WHO category at the time of inclusion and had a higher CRP level on admission and treatment initiation. Patients receiving Tocilizumab were treated with remdesivir more often and only patients in the baricitinib group were treated with monoclonal antibodies. Other characteristics did not differ significantly. In-hospital mortality (18% vs. 11%, p = 0.229), progression to MV (19% vs. 11%, p = 0.173) and LOS (13 vs. 12 days, p = 0.114) did not differ between groups. Side effects were equally distributed between groups, except ALAT elevation which was significantly more often observed in the tocilizumab group (43% vs. 25%, p = 0.021). CONCLUSIONS: In-hospital mortality, progression to MV and LOS were not significantly different in patients treated with tocilizumab or baricitinib additionally to standard of care. Both drugs seem equally effective but further head-to-head trials are needed.

Comparison of clinical characteristics among patients infected with alpha vs. delta SARS-CoV-2 variants.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has undergone different molecular changes, sprouting genetic variants of the original wildtype. Clinical comparisons between patients infected with alpha versus delta are scarce. METHODS: In this retrospective observational study, adult patients hospitalized with coronavirus disease 2019 (COVID-19) due to confirmed SARS-CoV­2 alpha or delta infection were included. Patient characteristics, virologic and laboratory parameters, as well as the clinical course were compared in patients infected with alpha vs. delta variants. RESULTS: A total of 106 patients infected with alpha and 215 patients infected with delta were included. Patients infected with the delta variant were admitted to hospital earlier after symptom onset (6 vs. 7 days, p < 0.001). Blood levels of C­reactive protein (43.3 vs. 62.9 mg/l, p = 0.02) and neutrophil count (3.81 vs. 4.53 G/l, p = 0.06) were lower in delta patients. Furthermore, at hospital admission cycle threshold (CT) values were significantly lower in patients infected with the delta variant (22.3 vs. 24.9, p < 0.001). Patients infected with the delta variant needed supplemental oxygen less often during disease course (50% vs. 64%, p = 0.02). Furthermore, there was a statistically non-significant trend towards a lower ICU admission rate among delta patients (16% vs. 24%, p = 0.08) CONCLUSION: Patients diagnosed with the delta variant were admitted to the hospital earlier, had a less severe course of disease and a higher viral replication on admission. This may provide a window of opportunity for antivirals in the hospital setting.

Percutaneous Auricular Vagus Nerve Stimulation Reduces Inflammation in Critical Covid-19 Patients

Covid-19 is an infectious disease associated with cytokine storms and derailed sympatho-vagal balance leading to respiratory distress, hypoxemia and cardiovascular damage. We applied the auricular vagus nerve stimulation to modulate the parasympathetic nervous system, activate the associated anti-inflammatory pathways, and reestablish the abnormal sympatho-vagal balance. aVNS is performed percutaneously using miniature needle electrodes in ear regions innervated by the auricular vagus nerve. In terms of a randomized prospective study, chronic aVNS is started in critical, but not yet ventilated Covid-19 patients during their stay at the intensive care unit. The results show decreased pro-inflammatory parameters, e.g. a reduction of CRP levels by 32% after 1 day of aVNS and 80% over 7 days (from the mean 151.9 mg/dl to 31.5 mg/dl) or similarly a reduction of TNFalpha levels by 58.1% over 7 days (from a mean 19.3 pg/ml to 8.1 pg/ml) and coagulation parameters, e.g. reduction of DDIMER levels by 66% over 7 days (from a mean 4.5 μg/ml to 1.5 μg/ml) and increased anti-inflammatory parameters, e.g. an increase of IL-10 levels by 66% over 7 days (from the mean 2.7 pg/ml to 7 pg/ml) over the aVNS duration without collateral effects. aVNS proved to be a safe clinical procedure and could effectively supplement treatment of critical Covid-19 patients while preventing devastating over-inflammation.

Rapid Detection of Bacterial and Fungal Pathogens Using the T2MR versus Blood Culture in Patients with Severe COVID-19.

A high rate of bacterial and fungal superinfections was reported in critically ill patients with COVID-19. However, diagnosis can be challenging. The aim of this study is to evaluate the sensitivity and the clinical utility of the point-of-care method T2 magnetic resonance (T2MR) with the gold standard: the blood culture. T2MR can potentially detect five different Candida species and six common bacteria (so-called "ESKAPE" pathogens including Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, Acinet`obacter baumanii, Pseudomonas aeruginosa, and Enterococcus faecium). If superinfection was suspected in patients with COVID-19 admitted to the intensive care unit, blood culture and two panels of T2MR were performed. Eighty-five diagnostic bundles were performed in 60 patients in total. T2MR detected an ESKAPE pathogen in 9 out of 85 (10.6%) samples, compared to BC in 3 out of 85 (3.5%). A Candida species was detected in 7 of 85 (8.2%) samples of T2MR compared to 1 out of 85(1.2%) in blood culture. The mean time to positive test result in samples with concordant positive results was 4.5 h with T2MR and 52.5 h with blood culture. The additional use of T2MR enables a highly sensitive and rapid detection of ESKAPE and Candida pathogens. IMPORTANCE Coronavirus disease 2019 (COVID-19) has led to a high number of deaths since the beginning of the pandemic worldwide. One of the reasons is the high number of bacterial and fungal superinfections in patients suffering from critical disease. However, diagnosis is often challenging. In this study we could show that the additional use of the culture-independent method T2MR did not only show a much higher detection rate of bacterial and fungal pathogens but also a significantly shorter time until detection and therapy change compared to the gold standard: the blood culture. The implementation of T2MRin the care of patients with severe course of COVID-19 might lead to an earlier sufficient antimicrobial therapy and as a result lower mortality and less use of broad-spectrum unnecessary therapy reducing the risk of resistance development.

Platelet Phenotype Analysis of COVID-19 Patients Reveals Progressive Changes in the Activation of Integrin αIIbß3, F13A1, the SARS-CoV-2 Target EIF4A1 and Annexin A5.

Background: The fatal consequences of an infection with severe acute respiratory syndrome coronavirus 2 are not only caused by severe pneumonia, but also by thrombosis. Platelets are important regulators of thrombosis, but their involvement in the pathogenesis of COVID-19 is largely unknown. The aim of this study was to determine their functional and biochemical profile in patients with COVID-19 in dependence of mortality within 5-days after hospitalization. Methods: The COVID-19-related platelet phenotype was examined by analyzing their basal activation state via integrin αIIbß3 activation using flow cytometry and the proteome by unbiased two-dimensional differential in-gel fluorescence electrophoresis. In total we monitored 98 surviving and 12 non-surviving COVID-19 patients over 5 days of hospital stay and compared them to healthy controls (n = 12). Results: Over the observation period the level of basal αIIbß3 activation on platelets from non-surviving COVID-19 patients decreased compared to survivors. In line with this finding, proteomic analysis revealed a decrease in the total amount of integrin αIIb (ITGA2B), a subunit of αIIbß3, in COVID-19 patients compared to healthy controls; the decline was even more pronounced for the non-survivors. Consumption of the fibrin-stabilizing factor coagulation factor XIIIA (F13A1) was higher in platelets from COVID-19 patients and tended to be higher in non-survivors; plasma concentrations of the latter also differed significantly. Depending on COVID-19 disease status and mortality, increased amounts of annexin A5 (ANXA5), eukaryotic initiation factor 4A-I (EIF4A1), and transaldolase (TALDO1) were found in the platelet proteome and also correlated with the nasopharyngeal viral load. Dysregulation of these proteins may play a role for virus replication. ANXA5 has also been identified as an autoantigen of the antiphospholipid syndrome, which is common in COVID-19 patients. Finally, the levels of two different protein disulfide isomerases, P4HB and PDIA6, which support thrombosis, were increased in the platelets of COVID-19 patients. Conclusion: Platelets from COVID-19 patients showed significant changes in the activation phenotype, in the processing of the final coagulation factor F13A1 and the phospholipid-binding protein ANXA5 compared to healthy subjects. Additionally, these results demonstrate specific alterations in platelets during COVID-19, which are significantly linked to fatal outcome.

A Rapid, Highly Sensitive and Open-Access SARS-CoV-2 Detection Assay for Laboratory and Home Testing.

RT-qPCR-based diagnostic tests play important roles in combating virus-caused pandemics such as Covid-19. However, their dependence on sophisticated equipment and the associated costs often limits their widespread use. Loop-mediated isothermal amplification after reverse transcription (RT-LAMP) is an alternative nucleic acid detection method that overcomes these limitations. Here, we present a rapid, robust, and sensitive RT-LAMP-based SARS-CoV-2 detection assay. Our 40-min procedure bypasses the RNA isolation step, is insensitive to carryover contamination, and uses a colorimetric readout that enables robust SARS-CoV-2 detection from various sample types. Based on this assay, we have increased sensitivity and scalability by adding a nucleic acid enrichment step (Bead-LAMP), developed a version for home testing (HomeDip-LAMP), and identified open-source RT-LAMP enzymes that can be produced in any molecular biology laboratory. On a dedicated website, rtlamp.org (DOI: 10.5281/zenodo.6033689), we provide detailed protocols and videos. Our optimized, general-purpose RT-LAMP assay is an important step toward population-scale SARS-CoV-2 testing.

Management of hospitalized influenza A patients during the season 2018/19 : Comparison of three medical departments and the effect on outcome and antibiotic usage.

BACKGROUND: Diagnosis and treatment of influenza patients are often provided across several medical specialties. We compared patient outcomes at an infectious diseases (ID), a rheumatology (Rheu) and a pulmonology (Pul) department. MATERIAL AND METHODS: In this prospective observational multicenter study we included all influenza positive adults who were hospitalized and treated at flu isolation wards in three hospitals in Vienna during the season 2018/2019. RESULTS: A total of 490 patients (49% female) with a median age of 73 years (interquartile range [IQR] 61-82) were included. No differences regarding age, sex and most underlying diseases were present at admission. Frequencies of the most common complications differed: acute kidney failure (ID 12.7%, Rheu 21.2%, Pulm 37.1%, p < 0.001), acute heart failure (ID 4.3%, Rheu 17.1%, Pulm 14.4%, p < 0.001) and respiratory insufficiency (ID 45.1%, Rheu 41.5%, Pulm 56.3%, p = 0.030). Oseltamivir prescription was lowest at the pulmonology flu ward (ID 79.6%, Rheu 90.5%, Pulm 61.7%, p < 0.001). In total 176 patients (35.9%) developed pneumonia. Antibiotic selection varied between the departments: amoxicillin/clavulanic acid (ID 28.9%, Rheu 63.8%, Pulm 5.9%, p < 0.001), cefuroxime (ID 28.9%, Rheu 1.3%, Pulm 0%, p < 0.001), 3rd generation cephalosporins (ID 4.4%, Rheu 5%, Pulm 72.5%, p < 0.001), doxycycline (ID 17.8%, Rheu 0%, Pulm 0%, p < 0.001). The median length of stay was significantly different between wards: ID 6 days (IQR 5-8), Rheu 6 days (IQR 5-7) and Pulm 7 days (IQR 5-9.5, p = 0.034). In-hospital mortality was 4.3% and did not differ between specialties. CONCLUSION: We detected differences in oseltamivir usage, length of in-hospital stay and antibiotic choices for pneumonia. Influenza-associated mortality was unaffected by specialty.

Evaluation of Five Commercial SARS-CoV-2 Antigen Tests in a Clinical Setting.

BACKGROUND: Point-of-care antigen tests (AgTs) for the detection of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) enable the rapid testing of infected individuals and are easy-to-use. However, there are few studies evaluating their clinical use. OBJECTIVE: The present study aimed to evaluate and compare the clinical performance characteristics of various commercial SARS-CoV-2 AgTs. DESIGN: The sensitivity of five AgTs, comprising four rapid antigen tests (RAT; AMP Rapid Test SARS-CoV-2 Ag, NADAL COVID-19 Antigen Rapid Test, CLINITEST Rapid COVID-19 Antigen Test, and Roche SARS-CoV-2 Rapid Antigen Test) and one sandwich chemiluminescence immunoassay (CLIA; LIAISON SARS-CoV-2 Assay), were evaluated in 300 nasopharyngeal (NP) swabs. Reverse transcriptase (RT) polymerase chain reaction (PCR) was used as a reference method. PARTICIPANTS: NP swabs were collected from patients admitted to hospital due to COVID-19. KEY RESULTS: Sensitivities of the AgTs ranged from 64.9 to 91.7% for samples with RT-PCR cycle threshold (Ct) values lower than 30 and were 100% for cycle threshold (Ct) values lower than 20. The highest sensitivity was observed for CLINITEST Rapid COVID-19 Antigen Test, and Roche SARS-CoV-2 rapid antigen test. Multivariate analysis using time from symptom onset and the Ct value for AgT sensitivity showed an inverse correlation. Further, the female sex was an independent factor of lower RAT sensitivity. CONCLUSIONS: Antigen tests from NP swab samples show high sensitivity in patients with a Ct value < 20. The best clinical sensitivity can be obtained using AgTs within the first 6 days after symptom onset.

Platelets and Antiplatelet Medication in COVID-19-Related Thrombotic Complications.

Coronavirus disease 2019 (COVID-19) induces a hypercoagulatory state that frequently leads to thromboembolic complications. Whereas anticoagulation is associated with reduced mortality, the role of antiplatelet therapy in COVID-19 is less clear. We retrospectively analyzed the effect of anticoagulation and antiplatelet therapy in 578 hospitalized patients with COVID-19 and prospectively monitored 110 patients for circulating microthrombi and plasma markers of coagulation in the first week of admission. Moreover, we determined platelet shape change and also thrombi in postmortem lung biopsies in a subset of patients with COVID-19. We observed no association of antiplatelet therapy with COVID-19 survival. Adverse outcome in COVID-19 was associated with increased activation of the coagulation cascade, whereas circulating microthrombi did not increase in aggravated disease. This was in line with analysis of postmortem lung biopsies of patients with COVID-19, which revealed generally fibrin(ogen)-rich and platelet-low thrombi. Platelet spreading was normal in severe COVID-19 cases; however, plasma from patients with COVID-19 mediated an outcome-dependent inhibitory effect on naïve platelets. Antiplatelet medication disproportionally exacerbated this platelet impairment in plasma of patients with fatal outcome. Taken together, this study shows that unfavorable outcome in COVID-19 is associated with a profound dysregulation of the coagulation system, whereas the contribution of platelets to thrombotic complications is less clear. Adverse outcome may be associated with impaired platelet function or platelet exhaustion. In line, antiplatelet therapy was not associated with beneficial outcome.

A Model Predicting Mortality of Hospitalized Covid-19 Patients Four Days After Admission: Development, Internal and Temporal-External Validation.

Objective: To develop and validate a prognostic model for in-hospital mortality after four days based on age, fever at admission and five haematological parameters routinely measured in hospitalized Covid-19 patients during the first four days after admission. Methods: Haematological parameters measured during the first 4 days after admission were subjected to a linear mixed model to obtain patient-specific intercepts and slopes for each parameter. A prediction model was built using logistic regression with variable selection and shrinkage factor estimation supported by bootstrapping. Model development was based on 481 survivors and 97 non-survivors, hospitalized before the occurrence of mutations. Internal validation was done by 10-fold cross-validation. The model was temporally-externally validated in 299 survivors and 42 non-survivors hospitalized when the Alpha variant (B.1.1.7) was prevalent. Results: The final model included age, fever on admission as well as the slope or intercept of lactate dehydrogenase, platelet count, C-reactive protein, and creatinine. Tenfold cross validation resulted in a mean area under the receiver operating characteristic curve (AUROC) of 0.92, a mean calibration slope of 1.0023 and a Brier score of 0.076. At temporal-external validation, application of the previously developed model showed an AUROC of 0.88, a calibration slope of 0.95 and a Brier score of 0.073. Regarding the relative importance of the variables, the (apparent) variation in mortality explained by the six variables deduced from the haematological parameters measured during the first four days is higher (explained variation 0.295) than that of age (0.210). Conclusions: The presented model requires only variables routinely acquired in hospitals, which allows immediate and wide-spread use as a decision support for earlier discharge of low-risk patients to reduce the burden on the health care system. Clinical Trial Registration: Austrian Coronavirus Adaptive Clinical Trial (ACOVACT); ClinicalTrials.gov, identifier NCT04351724.

Sensitivity and Specificity of SARS-CoV-2 Rapid Antigen Detection Tests Using Oral, Anterior Nasal, and Nasopharyngeal Swabs: a Diagnostic Accuracy Study.

The objective of our study was to evaluate the sensitivity and specificity of rapid antigen detection tests versus those of reverse transcriptase PCR (RT-PCR) using oral, anterior nasal, and nasopharyngeal swabs. The underlying prospective, diagnostic case-control-type accuracy study included 87 hospitalized and nonhospitalized participants in a positive and a negative sample cohort between 16 March and 14 May 2021 in two hospitals in Vienna. SARS-CoV-2 infection status was confirmed by RT-PCR. Participants self-performed one oral and one anterior nasal swab for the rapid antigen test, immediately followed by two nasopharyngeal swabs for the rapid antigen test and RT-PCR by the investigator. Test results were read after 15 min, and participants completed a questionnaire in the meantime. Test parameters were calculated based on the evaluation of 87 participants. The overall sensitivity of rapid antigen detection tests versus that of RT-PCR with oral, anterior nasal, and nasopharyngeal samples was 18.18% (95% confidence interval [CI] 8.19% to 32.71%), 63.04% (95% CI 47.55% to 76.79%), and 73.33% (95% CI 58.06% to 85.4%), respectively. All sampling methods had a test specificity of 100% regardless of the cycle threshold (CT) value. Rapid antigen detection tests using self-collected anterior nasal swabs proved to be as sensitive as and more tolerable than professionally collected nasopharyngeal swabs for CT values up to 30 determined by RT-PCR. This finding illustrates the reliability of tests obtained by adequate self-collected anterior nasal specimen. Sensitivity was dependent upon the CT value for each sampling method. While the main advantage of rapid antigen detection tests is the immediate availability of results, PCR should be preferred in crucial settings wherever possible. IMPORTANCE Rapid antigen detection devices for SARS-CoV-2 represent a valuable tool for monitoring the spread of infection. However, the reliability of the tests depends largely on the test performance and the respective sampling method. Nasopharyngeal swabs mark the gold standard for sample collection in suspected respiratory tract infections but are unsuitable for widespread application, as they must be performed by medically trained personnel. With the underlying study, the head-to-head test performance and the usability of self-collected samples for SARS-CoV-2 detection using rapid antigen detection devices were evaluated. The results confirm similar sensitivity of self-collected anterior nasal swabs to that of professionally collected nasopharyngeal swabs for patients with a CT of < 30 determined by RT-PCR.

Age Related Differences in Monocyte Subsets and Cytokine Pattern during Acute COVID-19-A Prospective Observational Longitudinal Study.

The COVID-19 pandemic drastically highlighted the vulnerability of the elderly population towards viral and other infectious threats, illustrating that aging is accompanied by dysregulated immune responses currently summarized in terms like inflammaging and immunoparalysis. To gain a better understanding on the underlying mechanisms of the age-associated risk of adverse outcome in individuals experiencing a SARS-CoV-2 infection, we analyzed the impact of age on circulating monocyte phenotypes, activation markers and inflammatory cytokines including interleukin 6 (IL-6), IL-8 and tumor necrosis factor (TNF) in the context of COVID-19 disease progression and outcome in 110 patients. Our data indicate no age-associated differences in peripheral monocyte counts or subset composition. However, age and outcome are associated with differences in monocyte activation status. Moreover, a distinct cytokine pattern of IL-6, IL-8 and TNF in elderly survivors versus non-survivors, which consolidates over the time of hospitalization, suggests that older patients with adverse outcomes experience an inappropriate immune response, reminiscent of an inflammaging driven immunoparalysis. Our study underscores the value, necessity and importance of longitudinal monitoring in elderly COVID-19 patients, as dynamic changes after symptom onset can be observed, which allow for a differentiated insight into confounding factors that impact the complex pathogenesis following an infection with SARS-CoV-2.

Muscle involvement in SARS-CoV-2 infection.

BACKGROUND AND PURPOSE: Since the outbreak of the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) pandemic, several reports indicated neurological involvement in COVID-19 disease. Muscle involvement has also been reported as evidenced by creatine kinase (CK) elevations and reports of myalgia. METHODS: Creatine kinase, markers of inflammation, pre-existing diseases and statin use were extracted from records of Austrian hospitalised COVID-19 patients. Disease severity was classified as severe in case of intensive care unit (ICU) admission or mortality. COVID-19 patients were additionally compared to an historical group of hospitalised influenza patients. RESULTS: Three hundred fifty-one patients with SARS-CoV-2 and 258 with influenza were included in the final analysis. CK was elevated in 27% of COVID-19 and in 28% of influenza patients. CK was higher in severe COVID-19 as were markers of inflammation. CK correlated significantly with inflammation markers, which had an independent impact on CK when adjusted for demographic variables and disease severity. Compared to influenza patients, COVID-19 patients were older, more frequently male, had more comorbidities, and more frequently had a severe disease course. Nevertheless, influenza patients had higher baseline CK than COVID-19, and 35.7% of intensive care unit (ICU)-admitted patients had CK levels >1,000 U/L compared to only 4.7% of ICU-admitted COVID-19 patients. CONCLUSIONS: HyperCKemia occurs in a similar frequency in COVID-19 and influenza infection. CK levels were lower in COVID-19 than in influenza in mild and severe disease. CK levels strongly correlate with disease severity and markers of inflammation. To date, it remains unclear whether hyperCKemia is due to a virus-triggered inflammatory response or direct muscle toxicity.

Adverse Outcome in COVID-19 Is Associated With an Aggravating Hypo-Responsive Platelet Phenotype.

Thromboembolic complications are frequently observed in Coronavirus disease 2019 (COVID-19). While COVID-19 is linked to platelet dysregulation, the association between disease outcome and platelet function is less clear. We prospectively monitored platelet activation and reactivity in 97 patients during the first week of hospitalization and determined plasma markers of platelet degranulation and inflammation. Adverse outcome in COVID-19 was associated with increased basal platelet activation and diminished platelet responses, which aggravated over time. Especially GPIIb/IIIa responses were abrogated, pointing toward impeded platelet aggregation. Moreover, platelet-leukocyte aggregate formation was diminished, pointing toward abrogated platelet-mediated immune responses in COVID-19. No general increase in plasma levels of platelet-derived granule components could be detected, arguing against platelet exhaustion. However, studies on platelets from healthy donors showed that plasma components in COVID-19 patients with unfavorable outcome were at least partly responsible for diminished platelet responses. Taken together this study shows that unfavorable outcome in COVID-19 is associated with a hypo-responsive platelet phenotype that aggravates with disease progression and may impact platelet-mediated immunoregulation.

Low-molecular-weight heparin use in coronavirus disease 2019 is associated with curtailed viral persistence: a retrospective multicentre observational study.

AIMS: Anticoagulation was associated with improved survival of hospitalized coronavirus disease 2019 (COVID-19) patients in large-scale studies. Yet, the development of COVID-19-associated coagulopathy (CAC) and the mechanism responsible for improved survival of anticoagulated patients with COVID-19 remain largely elusive. This investigation aimed to explore the effects of anticoagulation and low-molecular-weight heparin (LMWH) in particular on patient outcome, CAC development, thromboinflammation, cell death, and viral persistence. METHODS AND RESULTS: Data of 586 hospitalized COVID-19 patients from three different regions of Austria were evaluated retrospectively. Of these, 419 (71.5%) patients received LMWH and 62 (10.5%) received non-vitamin-K oral anticoagulants (NOACs) during hospitalization. Plasma was collected at different time points in a subset of 106 patients in order to evaluate markers of thromboinflammation (H3Cit-DNA) and the cell death marker cell-free DNA (cfDNA). Use of LMWH was associated with improved survival upon multivariable Cox regression (hazard ratio = 0.561, 95% confidence interval: 0.348-0.906). Interestingly, neither LMWH nor NOAC was associated with attenuation of D-dimer increase over time, or thromboinflammation. In contrast, anticoagulation was associated with a decrease in cfDNA during hospitalization, and curtailed viral persistence was observed in patients using LMWH leading to a 4-day reduction of virus positivity upon quantitative polymerase chain reaction [13 (interquartile range: 6-24) vs. 9 (interquartile range: 5-16) days, P = 0.009]. CONCLUSION: Time courses of haemostatic and thromboinflammatory biomarkers were similar in patients with and without LMWH, indicating either no effects of LMWH on haemostasis or that LMWH reduced hypercoagulability to levels of patients without LMWH. Nonetheless, anticoagulation with LMWH was associated with reduced mortality, improved markers of cell death, and curtailed viral persistence, indicating potential beneficial effects of LMWH beyond haemostasis, which encourages use of LMWH in COVID-19 patients without contraindications.

Detection of bacteria via multiplex PCR in respiratory samples of critically ill COVID-19 patients with suspected HAP/VAP in the ICU.

BACKGROUND: Critically ill Coronavirus disease 2019 (COVID-19) patients have high rates of bacterial superinfection. Multiplex polymerase chain reaction panels may be able to provide useful information about the incidence and spectrum of bacteria causing superinfections. METHODS: In this retrospective observational study we included all COVID-19 positive patients admitted to our intensive care unit with suspected hospital-acquired pneumonia/ventilator-associated pneumonia (HAP/VAP) in whom the BioFire® Pneumonia Panel (PP) was performed from tracheal aspirate or bronchoalveolar lavage fluid for diagnostic purposes. The aim of our study was to analyze the spectrum of pathogens detected with the PP. RESULTS: In this study 60 patients with a median age of 62.5 years were included. Suspected VAP was the most frequent (48/60, 80%) indication for performing the PP. Tracheal aspirate was the predominant sample type (50/60, 83.3%). The PP led to a negative, monomicrobial and polymicrobial result in 36.7%, 35% and 28.3% of the patients, respectively. The three most detected bacteria were Staphylococcus aureus (13/60, 21.7%), Klebsiella pneumoniae (12/60, 20%) and Haemophilus influenzae (9/60, 15%). Neither atypical bacteria nor resistance genes were detected. Microbiological culture of respiratory specimens was performed in 36 (60%) patients concomitantly. The PP and microbiological culture yielded a non-concordant, partial concordant and completely concordant result in 13.9% (5/36), 30.6% (11/36) and 55.6% (20/36) of the analyzed samples, respectively. CONCLUSION: In critically ill COVID-19 patients with suspected HAP/VAP results of the PP and microbiological culture methods were largely consistent. In our cohort, S. aureus and K. pneumoniae were the most frequently detected organisms. A higher diagnostic yield may be achieved if both methods are combined.