Haemostatic differences between SARS-CoV-2 PCR-positive and negative patients at the time of hospital admission.

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is associated with thrombosis. We conducted a cohort study of consecutive patients, suspected of SARS-CoV-2 infection presented to the emergency department. We investigated haemostatic differences between SARS-CoV-2 PCR positive and negative patients, with dedicated coagulation analysis. The 519 included patients had a median age of 66 years, and 52.5% of the patients were male. Twenty-six percent of the patients were PCR-positive for SARS-CoV-2.PCR positive patients had increased levels of fibrinogen and (active) von Willebrand Factor (VWF) and decreased levels of protein C and α2-macroglobulin compared to the PCR negative patients. In addition, we found acquired activated protein C resistance in PCR positive patients. Furthermore, we found that elevated levels of factor VIII and VWF and decreased levels of ADAMTS-13 were associated with an increased incidence of thrombosis in PCR positive patients. In conclusion, we found that PCR positive patients had a pronounced prothrombotic phenotype, mainly due to an increase of endothelial activation upon admission to the hospital. These findings show that coagulation tests may be considered useful to discriminate severe cases of COVID-19 at risk for thrombosis.

Low prevalence of SARS-CoV-2 in plasma of COVID-19 patients presenting to the emergency department.

Correct and reliable identification of SARS-CoV-2 in COVID-19 suspected patients is essential for diagnosis. Respiratory samples should always be tested with real-time PCR for SARS-CoV-2. In addition, blood samples have been tested, but without consistent results and therefore the added value of this sample type is unknown. The aim of this study was to determine the prevalence of SARS-CoV-2 by real-time PCR in blood samples obtained from PCR-proven COVID-19 patients and in addition to elaborate on the potential use of blood for diagnostics. In this single center study, blood samples drawn from patients at the emergency department with proven COVID-19 infection based on a positive SARS-CoV-2 PCR in respiratory samples were tested for the presence of SARS-CoV-2. Samples from 118 patients were selected, of which 102 could be included in the study (median age was 65 (IQR 10), 65.7 % men). In six (5.9 %) of the tested samples, SARS-CoV-2 was identified by real-time PCR. In conclusion, SARS-CoV-2 can be detected by real-time PCR in plasma samples from patients with proven COVID-19, but only in a minority of the patients. Plasma should therefore not be used as primary sample in an acute phase setting to identify SARS-CoV-2 infection. These findings are important to complete the knowledge on possible sample types to test to diagnose COVID-19.