Role of vaccination and anti-SARS-CoV-2 antibodies in the clinical outcome of hospitalized COVID-19 patients.

Background: Although vaccination has considerably reduced the risk of hospitalization and death from COVID19, the impact of vaccination and anti-SARS-CoV-2 antibody status on the outcome of patients who required hospitalization has been poorly investigated. Material and methods: A prospective observational study in 232 patients hospitalized for COVID19 was carried out from October 2021 to January 2022 to evaluate the role on patient outcome of their vaccination and anti-SARS-CoV-2 antibody status and titer, comorbidities, analytical determinations, clinical presentation at admission, treatments and requirements for respiratory support. Cox regression and survival analyzes were performed. The SPSS and "R" programs were used. Results: Patients with complete vaccination schedule had higher S-protein antibody titers (log10 3.73 [2.83-4.6] UI/ml vs 1.6 [2.99-2.61] UI/ml; p < 0.001), lower probability of radiographic worsening (21.6% vs. 35.4%; p = 0.005), less likely required high doses of dexamethasone (28.4% vs. 45.4%; p = 0.012), high-flow oxygen (20.6% vs. 35.4%; p = 0.02), ventilation (13.7% vs, 33.8%; p = 0.001) and intensive care admissions (10.8% vs. 32.6%; p < 0.001). Remdesivir (HR = 0.38; p < 0.001) and complete vaccination schedule (HR = 0.34; p = 0.008) were protective factors. No differences in antibody status were detected between groups (HR = 0.58; p = 0.219). Conclusions: SARS-CoV-2 vaccination was associated with higher S-protein antibody titers and lower probability of radiological progression, immunomodulators requirement and respiratory support or death. However, vaccination but not antibody titters protected from adverse events pointing a role of immune-protective mechanisms in addition to humoral response.

Antecedentes: Aunque la vacunación ha reducido considerablemente el riesgo de hospitalización y muerte por COVID-19, se ha investigado poco el impacto de la vacunación y el estado de los anticuerpos anti-SARS-CoV-2 en la evolución de los pacientes que requieren hospitalización. Material y métodos: Se realizó un estudio observacional prospectivo en 232 pacientes hospitalizados por COVID-19 desde octubre del 2021 hasta enero del 2022 para evaluar el impacto en la evolución clínica del estado vacunal, el título de anticuerpos anti-SARS-CoV-2, la presencia de comorbilidades, analítica, la clínica al ingreso, tratamientos y soporte respiratorio. Se realizaron análisis de supervivencia y regresión de Cox. Se utilizaron los programas SPSS y «R¼. Resultados: Los pacientes con esquema de vacunación completo presentaron títulos de anticuerpos contra la proteína S más elevados (log10 3,73 [2,83-4,6] UI/mL vs. 1,6 [2,99-2,61] UI/mL; p < 0,001), menor probabilidad de empeoramiento radiográfico (21,6 vs. 35,4%; p = 0,005), requirieron con menor probabilidad dosis elevadas de dexametasona (28,4 vs. 45,4%; p = 0,012), oxígeno de alto flujo (20,6 vs. 35,4%; p = 0,02), ventilación (13,7 vs. 33,8%; p = 0,001) e ingresos en cuidados intensivos (10,8 vs. 32,6%; p < 0,001). El remdesivir (HR = 0,38; p < 0,001) y el esquema completo de vacunación (HR = 0,34; p = 0,008) fueron factores protectores de mala evolución. No se detectaron diferencias en el estado de los anticuerpos entre los grupos (HR = 0,58; p = 0,219). Conclusiones: La vacunación contra el SARS-CoV-2 se asoció con mayores títulos de anticuerpos contra la proteína S y menor probabilidad de progresión radiológica, requerimiento de inmunomoduladores y soporte respiratorio o muerte. Sin embargo, la vacunación, pero no los títulos de anticuerpos, protegió de los eventos adversos, lo que indica un papel de los mecanismos de protección inmunológica además de la respuesta humoral.

Time from symptoms onset to remdesivir is associated with the risk of ICU admission: a multicentric analyses.

BACKGROUND: Shorter duration of symptoms before remdesivir has been associated with better outcomes. Our goal was to evaluate variables associated with the need of ICU admission in a cohort of hospitalized patients for COVID-19 under remdesivir including the period from symptoms onset to remdesivir. METHODS: We conducted a retrospective multicentric study analysing all patients admitted with COVID-19 in 9 Spanish hospitals who received treatment with remdesivir in October 2020. The main outcome was the need of ICU admission after 24 h of the first dose of remdesivir. RESULTS: In our cohort of 497 patients, the median of days from symptom onset to remdesivir was 5 days, and 70 of them (14.1%) were later admitted into ICU. The clinical outcomes associated with ICU admission were days from symptoms onset (5 vs. 6; p = 0.023), clinical signs of severe disease (respiratory rate, neutrophil count, ferritin levels and very-high mortality rate in SEIMC-Score) and the use of corticosteroids and anti-inflammatory drugs before ICU. The only variable significatively associated with risk reduction in the Cox-regression analyses was ≤ 5 days from symptoms onset to RDV (HR: 0.54, CI95%: 0.31-0.92; p = 0.024). CONCLUSION: For patients admitted to the hospital with COVID-19, the prescription of remdesivir within 5 days from symptoms onset diminishes the need of ICU admission.

Remdesivir plus dexamethasone is associated to improve the clinical outcome of COVID-19 hospitalized patients regardless of their vaccination status Remdesivir más dexametasona se asocian a una reducción de los eventos clínicos en los pacientes hospitalizados por COVID-19, independientemente de su estado de vacunación

Introduction Remdesivir seems to reduce the risk of hospitalization and improve clinical outcome in hospitalized patients with COVID-19. Objectives To compare the clinical outcome of COVID-19 hospitalized patients treated with remdesivir plus dexamethasone versus dexamethasone alone, according to their vaccination status. Material and methods A retrospective observational study was carried out in 165 patients hospitalized for COVID-19 from October 2021 to January 2022. Multivariate logistic regression, Kaplan–Meier and the log-rank tests were used to evaluate the event (need for ventilation or death). Results Patients treated with remdesivir plus dexamethasone (n = 87) compared with dexamethasone alone (n = 78) showed similar age (60 ± 16, 47–70 vs. 62 ± 37, 51–74 years) and number of comorbidities: 1 (0–2) versus 1.5 (1–3). Among 73 fully vaccinated patients, 42 (47.1%) were in remdesivir plus dexamethasone and 31 (41%) in dexamethasone alone. Patients treated with remdesivir plus dexamethasone needed intensive care less frequently (17.2% vs. 31%;p = 0.002), high-flow oxygen (25.3% vs. 50.0%;p = 0.002) and non-invasive mechanical ventilation (16.1% vs. 47.4%;p < 0.001). Furthermore, they had less complications during hospitalization (31.0% vs. 52.6%;p = 0.008), need of antibiotics (32.2% vs. 59%;p = 0.001) and radiologic worsening (21.8% vs. 44.9%;p = 0.005). Treatment with remdesivir plus dexamethasone (aHR, 0.26;95% CI: 0.14–0.48;p < 0.001) and vaccination (aHR 0.39;95% CI: 0.21–0.74) were independent factors associated with lower progression to mechanical ventilation or death. Conclusions Remdesivir in combination with dexamethasone and vaccination independently and synergistically protects hospitalized COVID-19 patients requiring oxygen therapy from progression to severe disease or dead.

Whole Sequencing and Detailed Analysis of SARS-CoV-2 Genomes in Southeast Spain: Identification of Recurrent Mutations in the 20E (EU1) Variant with Some Clinical Implications.

During the COVID-19 pandemic caused by SARS-CoV-2, new waves have been associated with new variants and have the potential to escape vaccinations. Therefore, it is useful to conduct retrospective genomic surveillance research. Herein, we present a detailed analysis of 88 SARS-CoV-2 genomes belonging to samples taken from COVID-19 patients from October 2020 to April 2021 at the "Reina Sofía" Hospital (Murcia, Spain) focused to variant appeared later. The results at the mentioned stage show the turning point since the 20E (EU1) variant was still prevalent (71.6%), but Alpha was bursting to 14.8%. Concern mutations have been found in 5 genomes classified as 20E (EU1), which were not characteristic of this still little evolved variant. Most of those mutations are found in the spike protein, namely Δ69-70, E484K, Q675H and P681H. However, a relevant deletion in ORF1a at positions 3675-3677 was also identified. These mutations have been reported in many later SARS-CoV-2 lineages, including Omicron. Taken together, our data suggest that preferential emergence mutations could already be present in the early converging evolution. Aside from this, the molecular information has been contrasted with clinical data. Statistical analyses suggest that the correlation between age and severity criteria is significantly higher in the viral samples with more accumulated changes.

Remdesivir plus dexamethasone is associated to improve the clinical outcome of COVID-19 hospitalized patients regardless of their vaccination status.

INTRODUCTION: Remdesivir seems to reduce the risk of hospitalization and improve clinical outcome in hospitalized patients with COVID-19. OBJECTIVES: To compare the clinical outcome of COVID-19 hospitalized patients treated with remdesivir plus dexamethasone versus dexamethasone alone, according to their vaccination status. MATERIAL AND METHODS: A retrospective observational study was carried out in 165 patients hospitalized for COVID-19 from October 2021 to January 2022. Multivariate logistic regression, Kaplan-Meier and the log-rank tests were used to evaluate the event (need for ventilation or death). RESULTS: Patients treated with remdesivir plus dexamethasone (n=87) compared with dexamethasone alone (n=78) showed similar age (60±16, 47-70 vs. 62±37, 51-74 years) and number of comorbidities: 1 (0-2) versus 1.5 (1-3). Among 73 fully vaccinated patients, 42 (47.1%) were in remdesivir plus dexamethasone and 31 (41%) in dexamethasone alone. Patients treated with remdesivir plus dexamethasone needed intensive care less frequently (17.2% vs. 31%; p=0.002), high-flow oxygen (25.3% vs. 50.0%; p=0.002) and non-invasive mechanical ventilation (16.1% vs. 47.4%; p<0.001). Furthermore, they had less complications during hospitalization (31.0% vs. 52.6%; p=0.008), need of antibiotics (32.2% vs. 59%; p=0.001) and radiologic worsening (21.8% vs. 44.9%; p=0.005). Treatment with remdesivir plus dexamethasone (aHR, 0.26; 95% CI: 0.14-0.48; p<0.001) and vaccination (aHR 0.39; 95% CI: 0.21-0.74) were independent factors associated with lower progression to mechanical ventilation or death. CONCLUSIONS: Remdesivir in combination with dexamethasone and vaccination independently and synergistically protects hospitalized COVID-19 patients requiring oxygen therapy from progression to severe disease or dead.

Role of vaccination and anti-SARS-CoV-2 antibodies in the clinical outcome of hospitalized COVID-19 patients.

BACKGROUND: Although vaccination has considerably reduced the risk of hospitalization and death from COVID19, the impact of vaccination and anti-SARS-CoV-2 antibody status on the outcome of patients who required hospitalization has been poorly investigated. MATERIAL AND METHODS: A prospective observational study in 232 patients hospitalized for COVID19 was carried out from October 2021 to January 2022 to evaluate the role on patient outcome of their vaccination and anti-SARS-CoV-2 antibody status and titer, comorbidities, analytical determinations, clinical presentation at admission, treatments and requirements for respiratory support. Cox regression and survival analyzes were performed. The SPSS and "R" programs were used. RESULTS: Patients with complete vaccination schedule had higher S-protein antibody titers (log10 3.73 [2.83-4.6]UI/ml vs 1.6 [2.99-2.61]UI/ml; p<0.001), lower probability of radiographic worsening (21.6% vs. 35.4%; p=0.005), less likely required high doses of dexamethasone (28.4% vs. 45.4%; p=0.012), high-flow oxygen (20.6% vs. 35.4%; p=0.02), ventilation (13.7% vs, 33.8%; p=0.001) and intensive care admissions (10.8% vs. 32.6%; p<0.001). Remdesivir (HR=0.38; p<0.001) and complete vaccination schedule (HR=0.34; p=0.008) were protective factors. No differences in antibody status were detected between groups (HR=0.58; p=0.219). CONCLUSIONS: SARS-CoV-2 vaccination was associated with higher S-protein antibody titers and lower probability of radiological progression, immunomodulators requirement and respiratory support or death. However, vaccination but not antibody titters protected from adverse events pointing a role of immune-protective mechanisms in addition to humoral response.

Papel de la vacunación y los anticuerpos anti-SARS-CoV-2 en el desenlace clínico de pacientes hospitalizados por COVID-19 Role of vaccination and anti-SARS-CoV-2 antibodies in the clinical outcome of hospitalized COVID-19 patients

Antecedentes: aunque la vacunación ha reducido considerablemente el riesgo de hospitalización y muerte por COVID19, se ha investigado poco el impacto de la vacunación y el estado de los anticuerpos anti-SARS-CoV-2 en la evolución de los pacientes que requieren hospitalización. Material y métodos: Se realizó un estudio observacional prospectivo en 232 pacientes hospitalizados por COVID19 desde octubre de 2021 hasta enero de 2022 para evaluar el impacto en la evolución clínica del estado vacunal, el título de anticuerpos anti-SARS-CoV-2, la presencia de comorbilidades, analítica, la clínica al ingreso, tratamientos y soporte respiratorio. Se realizaron análisis de supervivencia y regresión de Cox. Se utilizaron los programas SPSS y "R”. Resultados: Los pacientes con esquema de vacunación completo presentaron títulos de anticuerpos contra la proteína S más elevados (log10 3,73 [2,83-4,6] UI/ml vs 1,6 [2,99-2,61] UI UI/ml;p<0,001), menor probabilidad de empeoramiento radiográfico (21,6% vs 35,4%;p=0,005), requirieron con menor probabilidad dosis elevadas de dexametasona (28,4% vs 45,4%;p=0,012), oxígeno de alto flujo (20,6% vs 35,4%;p=0,02), ventilación (13,7% vs, 33,8%;p=0,001) e ingresos en cuidados intensivos (10,8% vs. 32,6%;p<0,001). Remdesivir (HR=0,38;p<0,001) y esquema completo de vacunación (HR=0,34;p=0,008) fueron factores protectores de mala evolución. No se detectaron diferencias en el estado de los anticuerpos entre los grupos (HR=0,58;p=0,219) Conclusiones: La vacunación contra el SARS-CoV-2 se asoció con mayores títulos de anticuerpos contra la proteína S y menor probabilidad de progresión radiológica, requerimiento de inmunomoduladores y soporte respiratorio o muerte. Sin embargo, la vacunación, pero no los títulos de anticuerpos protegieron de los eventos adversos, lo que indica un papel de los mecanismos de protección inmunológica además de la respuesta humoral.

Saliva changes in composition associated to COVID-19: a preliminary study.

The coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV 2), is usually associated with a wide variety of clinical presentations from asymptomatic to severe cases. The use of saliva as a diagnostic and monitoring fluid has gained importance since it can be used to investigate the immune response and to direct quantification of antibodies against COVID-19. Additionally, the use of proteomics in saliva has allowed to increase  our understanding of the underlying pathophysiology of diseases, bringing new perspectives on diagnostics, monitoring, and treatment. In this work, we compared the salivary proteome of 10 patients with COVID-19, (five patients with mild and five patients with severe COVID-19) and ten control healthy patients. Through the application of proteomics, we have identified 30 proteins whose abundance levels differed between the COVID-19 groups and the control group. Two of these proteins (TGM3 and carbonic anhydrase-CA6) were validated by the measurement of gGT and TEA respectively, in 98 additional saliva samples separated into two groups: (1) COVID-19 group, integrated by 66 patients who tested positive for COVID-19 (2) control group, composed of 32 healthy individuals who did not show any sign of disease for at least four weeks and were negative for COVID-19 in RT-PCR. In the proteomic study there were observed upregulations in CAZA1, ACTN4, and ANXA4, which are proteins related to the protective response against the virus disturbance, and the upregulation of TGM3, that is correlated to the oxidative damage in pulmonary tissue. We also showed the downregulation in cystatins and CA6 that can be involved in the sensory response to stimulus and possibly related to the presence of anosmia and dysgeusia during the COVID-19. Additionally, the presence of FGB in patients with severe COVID-19 but not in mild COVID-19 patients could indicate a higher viral aggregation and activation in these cases. In conclusion, the salivary proteome in patients with COVID-19 showed changes in proteins related to the protective response to viral infection, and the altered sensory taste perception that occur during the disease. Moreover, gGT and TEA could be potential biomarkers of respiratory complications that can occurs during COVID 19 although further larger studies should be made to corroborate this.

Elevated levels of serum CDCP1 in individuals recovering from severe COVID-19 disease.

BACKGROUND: COVID-19 survivors report residual lung abnormalities after discharge from the hospital. The aim of this study was to identify biomarkers in serum and induced sputum samples from patients after hospitalization for COVID-19. METHODS: Patients admitted to hospitals in Spain with laboratory-confirmed COVID-19 were recruited for this study. SARS-CoV-2-infected patients were divided into groups with mild/moderate and severe disease according to the severity of their symptoms during hospitalization. Levels of 92 biomarkers were measured in serum and induced sputum samples. RESULTS: A total of 108 patients (46.2% severe cases) were included in this study. The median number of days after the onset of symptoms was 104. A significant difference was observed in diffusing capacity for carbon monoxide (DLCO), an indicator of lung function, whereby DLCO <80% was significantly lower in severe cases (p <0.001). Differences in inflammatory biomarkers were observed between patients with mild/moderate and severe disease. For some biomarkers, correlations in serum and induced sputum levels were detected. Independent predictors of severe disease were DLCO <80% and the serum CDCP1 value. CONCLUSIONS: Higher levels of CDCP1 remain after hospital discharge and are associated with the severity of COVID-19. The possible prognostic implications warrant further investigation.

Salivary Ferritin Changes in Patients with COVID-19.

High ferritin serum levels can be found in patients with macrophage activation syndrome, and increased serum ferritin due to cytokine storm have been reported in severe COVID-19 patients. Saliva is being increasingly used in COVID-19 tests as a diagnostic sample for virus detection and quantification. This study aimed to evaluate the possible changes in ferritin in saliva in COVID-19 patients. In addition, the effects of different inactivation SARS-CoV-2 treatments in ferritin measurements in saliva, the correlation between ferritin in saliva and serum, and the possible effects of correction of ferritin values by total protein were assessed. Ferritin was measured in saliva from healthy (n = 30) and COVID-19 (n = 65) patients with severe, (n = 18) or mild (n = 47) disease, depending on the need for nasal flow oxygen or assisted respiration. Ferritin was also measured in paired serum and saliva samples (n = 32) from healthy and COVID-19 patients. The evaluated inactivation protocols did not affect the assay's results except the addition of 0.5% SDS. Significantly higher ferritin was found in the saliva of COVID-19 patients (median; 25-75th percentile) (27.75; 9.77-52.2 µg/L), compared with healthy controls (4.21; 2.6-8.08 µg/L). Individuals with severe COVID-19 showed higher ferritin values in saliva (48.7; 18.7-53.9) than mild ones (15.5; 5.28-41.3 µg/L). Significant correlation (r = 0.425; p < 0.001) was found between serum and saliva in ferritin. Ferritin levels were higher in COVID-19 patients in serum and saliva, and the highest values were found in those patients presenting severe symptomatology. In conclusion, ferritin in saliva has the potential to be a biomarker to evaluate severity in patients with COVID-19.

Colchicine in Recently Hospitalized Patients with COVID-19: A Randomized Controlled Trial (COL-COVID).

BACKGROUND: Colchicine has been proposed as a potential therapy in coronavirus disease 2019 (COVID-19) due to their anti-inflammatory actions. METHODS: The COL-COVID study was a prospective, randomized, controlled and open-label clinical trial that compared colchicine added to standard treatment vs standard treatment in hospitalized COVID-19 patients that do not need mechanical ventilatory support. Colchicine was initiated within the first 48 hours of admission at a 1.5 mg loading dose, followed by 0.5 mg b.i.d. for one week and 0.5 mg per day for 28 days. The study endpoints were clinical status (7-points WHO ordinal scale) and inflammatory biomarkers (IL-6 and CRP). RESULTS: A total of 103 patients (51±12 years, 52% male) were randomly allocated to colchicine arm (n=52) and control arm (n=51). At day 28, all patients in the colchicine group were alive and discharged, whereas in the control group, two patients died in-hospital and one patient remained hospitalized. Clinical improvement in terms of changes on WHO scale at day 14 and 28 and time to 1-point clinical improvement did not differ between the two groups. Clinical deterioration (increase of at least 1-point in WHO scale) was observed in a higher proportion of cases in colchicine group (13.8%) vs control group (5.8%) (p=0.303); after adjustment by baseline risk factors and concomitant therapies, colchicine therapy was associated with a lower risk of clinical deterioration (p=0.030). Inflammatory biomarkers CRP and IL-6 concentrations course did not differ between the two arms. CONCLUSION: In hospitalized COVID-19 patients, colchicine treatment neither improved the clinical status, nor the inflammatory response, over the standard treatment. Nevertheless, a preventive effect for further clinical deterioration might be possible. TRIAL REGISTRATION: NCT04350320.

Evaluation of sample treatments in a safe and straightforward procedure for the detection of SARS-CoV-2 in saliva.

OBJECTIVES: To evaluate four sample treatments in a safe and straightforward procedure to detect SARS-CoV-2 in saliva. METHODS: Four sample treatments were evaluated in a 3-step procedure to detect SARS-CoV-2 in saliva: 1) heating at 95 °C for 5 min for sample inactivation; 2) sample treatment; 3) analysis by reverse-transcription loop-mediated isothermal amplification (LAMP). Saliva samples used were from infected individuals or were spiked with known quantities of viral particles. RESULTS: Three treatments had a limit of detection (LOD) of 500.000 viral particles per ml of saliva and could be used to detect individuals with potential to transmit the disease. The treatment of phosphate buffer, dithiothreitol, ethylenediaminetetraacetic acid and proteinase K, with an additional 95 °C heating step, yielded a lower LOD of 95; its sensitivity ranged from 100% in patients with nasopharyngeal swab reverse-transcriptase polymerase chain reaction cycle threshold values <20 to 47.8% for values >30. CONCLUSIONS: This report highlights the importance of an adequate sample treatment for saliva to detect SARS-CoV-2 and describes a flexible procedure that can be adapted to point-of-care. Although its sensitivity when LAMP is used is lower than reverse-transcriptase polymerase chain reaction, this procedure can contribute to COVID-19 control by detecting individuals able to transmit the disease.

Activating Killer-Cell Immunoglobulin-Like Receptors Are Associated With the Severity of Coronavirus Disease 2019.

BACKGROUND: Etiopathogenesis of the clinical variability of the coronavirus disease 2019 (COVID-19) remains mostly unknown. In this study, we investigate the role of killer cell immunoglobulin-like receptor (KIR)/human leukocyte antigen class-I (HLA-I) interactions in the susceptibility and severity of COVID-19. METHODS: We performed KIR and HLA-I genotyping and natural killer cell (NKc) receptors immunophenotyping in 201 symptomatic patients and 210 noninfected controls. RESULTS: The NKcs with a distinctive immunophenotype, suggestive of recent activation (KIR2DS4low CD16low CD226low CD56high TIGIThigh NKG2Ahigh), expanded in patients with severe COVID-19. This was associated with a higher frequency of the functional A-telomeric activating KIR2DS4 in severe versus mild and/or moderate patients and controls (83.7%, 55.7% and 36.2%, P < 7.7 × 10-9). In patients with mild and/or moderate infection, HLA-B*15:01 was associated with higher frequencies of activating B-telomeric KIR3DS1 compared with patients with other HLA-B*15 subtypes and noninfected controls (90.9%, 42.9%, and 47.3%; P < .002; Pc = 0.022). This strongly suggests that HLA-B*15:01 specifically presenting severe acute respiratory syndrome coronavirus 2 peptides could form a neoligand interacting with KIR3DS1. Likewise, a putative neoligand for KIR2DS4 could arise from other HLA-I molecules presenting severe acute respiratory syndrome coronavirus 2 peptides expressed on infected an/or activated lung antigen-presenting cells. CONCLUSIONS: Our results support a crucial role of NKcs in the clinical variability of COVID-19 with specific KIR/ligand interactions associated with disease severity.

Analytical validation of an automated assay for the measurement of adenosine deaminase (ADA) and its isoenzymes in saliva and a pilot evaluation of their changes in patients with SARS-CoV-2 infection.

OBJECTIVES: The aim of the present study was to validate a commercially available automated assay for the measurement of total adenosine deaminase (tADA) and its isoenzymes (ADA1 and ADA2) in saliva in a fast and accurate way, and evaluate the possible changes of these analytes in individuals with SARS-CoV-2 infection. METHODS: The validation, in addition to the evaluation of precision and accuracy, included the analysis of the effects of the main procedures that are currently being used for SARS-CoV-2 inactivation in saliva and a pilot study to evaluate the possible changes in salivary tADA and isoenzymes in individuals infected with SARS-CoV-2. RESULTS: The automated assay proved to be accurate and precise, with intra- and inter-assay coefficients of variation below 8.2%, linearity under dilution linear regression with R2 close to 1, and recovery percentage between 80 and 120% in all cases. This assay was affected when the sample is treated with heat or SDS for virus inactivation but tolerated Triton X-100 and NP-40. Individuals with SARS-CoV-2 infection (n=71) and who recovered from infection (n=11) had higher mean values of activity of tADA and its isoenzymes than healthy individuals (n=35). CONCLUSIONS: tADA and its isoenzymes ADA1 and ADA2 can be measured accurately and precisely in saliva samples in a rapid, economical, and reproducible way and can be analyzed after chemical inactivation with Triton X-100 and NP-40. Besides, the changes observed in tADA and isoenzymes in individuals with COVID-19 open the possibility of their potential use as non-invasive biomarkers in this disease.

Prognostic value of thrombin generation parameters in hospitalized COVID-19 patients.

SARS-CoV-2 infection increases the risk of thrombosis by different mechanisms not fully characterized. Although still debated, an increase in D-dimer has been proposed as a first-line hemostasis test associated with thromboembolic risk and unfavorable prognosis. We aim to systematically and comprehensively evaluate the association between thrombin generation parameters and the inflammatory and hypercoagulable state, as well as their prognostic value in COVID-19 patients. A total of 127 hospitalized patients with confirmed COVID-19, 24 hospitalized patients with SARS-CoV-2-negative pneumonia and 12 healthy subjects were included. Clinical characteristics, thrombin generation triggered by tissue factor with and without soluble thrombomodulin, and also by silica, as well as other biochemical parameters were assessed. Despite the frequent use of heparin, COVID-19 patients had similar thrombin generation to healthy controls. In COVID-19 patients, the thrombin generation lag-time positively correlated with markers of cell lysis (LDH), inflammation (CRP, IL-6) and coagulation (D-dimer), while the endogenous thrombin potential (ETP) inversely correlated with D-dimer and LDH, and positively correlated with fibrinogen levels. Patients with more prolonged lag-time and decreased ETP had higher peak ISTH-DIC scores, and had more severe disease (vascular events and death). The ROC curve and Kaplan Meier estimate indicated that the D-dimer/ETP ratio was associated with in-hospital mortality (HR 2.5; p = 0.006), and with the occurrence of major adverse events (composite end-point of vascular events and death) (HR 2.38; p = 0.004). The thrombin generation ETP and lag-time variables correlate with thromboinflammatory markers, and the D-dimer/ETP ratio can predict major adverse events in COVID-19.

Pulmonary long-term consequences of COVID-19 infections after hospital discharge.

OBJECTIVES: Coronavirus disease 2019 (COVID-19) survivors are reporting residual abnormalities after discharge from hospital. Limited information is available about this stage of recovery or the lingering effects of the virus on pulmonary function and inflammation. This study aimed to describe lung function in patients recovering from COVID-19 hospitalization and to identify biomarkers in serum and induced sputum samples from these patients. METHODS: Patients admitted to Spanish hospitals with laboratory-confirmed COVID-19 infection by a real-time PCR (RT-PCR) assay for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were recruited for this study. Each hospital screened their lists of discharged patients at least 45 days after symptom onset. SARS-CoV-2-infected patients were divided into mild/moderate and severe disease groups according to the severity of their symptoms during hospitalization. Patients' epidemiological and medical histories, comorbidities, chronic treatments, and laboratory parameters were evaluated. Pulmonary function tests, the standardized 6-minute walk test (6MWT) and chest computed tomography (CT) were also performed. The levels of proteases, their inhibitors, and shed receptors were measured in serum and induced sputum samples. RESULTS: A total of 100 patients with respiratory function tests were included in this study. The median number of days after the onset of symptoms was 104 (IQR 89.25, 126.75). COVID-19 was severe in 47% of patients (47/100). CT was normal in 48% of patients (48/100). Lung function was normal forced expiratory volume in one second (FEV1) ≥80%, forced vital capacity (FVC) ≥80%, FEV1/FVC ≥0.7, and diffusing capacity for carbon monoxide (DLCO) ≥80% in 92% (92/100), 94% (94/100), 100% (100/100) and 48% (48/100) of patients, respectively. Multivariate analysis showed that a DLCO <80% (OR 5.92; 95%CI 2.28-15.37; p < 0.0001) and a lower serum lactate dehydrogenase level (OR 0.98; 95%CI 0.97-0.99) were associated with the severe disease group of SARS-CoV-2 cases during hospital stay. CONCLUSIONS: A diffusion deficit (DLCO <80%) was still present after hospital discharge and was associated with the most severe SARS-CoV-2 cases.