Serum calprotectin can indicate current and future severity of COVID-19.

BACKGROUND: Predictive and prognostic biomarkers to guide 2019 novel coronavirus disease (COVID-19) are critically evolving. Dysregulated immune responses are the pivotal cause of severity mainly mediated by neutrophil activation. Thus, we evaluated the association of calprotectin, neutrophil secretory protein, and other mediators of inflammation with the severity and outcomes of COVID-19. METHODS: This two-center prospective study focused on PCR-proven COVID-19 patients (n = 76) with different clinical presentations and SARS-CoV-2 negative control subjects (n = 24). Serum calprotectin (SC) was compared with IL-6 and other laboratory parameters. RESULTS: Median levels of SC were significantly higher in COVID-19 patients in comparison to the control group (3760 vs. 2100 ng/ml, p < 0.0001). Elevated SC was significantly respective of disease severity (3760 ng/ml in mild up to 5700 ng/ml in severe cases, p < 0.0001). Moreover, the significant positive and negative correlations of SC with disease severity and oxygenation status indicated disease progression and respiratory worsening, respectively. It was found that SC was high in severe patients during hospitalization and significantly declined to normal after recovery. The logistic analysis identified the independent predictive power of SC for respiratory status or clinical severity. Indeed, SC behaved as a better discriminator for both outcomes, as it exhibited the largest area under the curve (receiver operating curve analysis), with the highest specificity and sensitivity when the predictive value of inflammatory biomarkers was compared. CONCLUSION: Calprotectin can be used as a reliable prognostic tool to predict the poor clinical outcomes of COVID-19 patients.

The benefits of Vitamin D in the COVID-19 pandemic: biochemical and immunological mechanisms.

In December 2019, a new infectious complication called CoronaVirus Infectious Disease-19, briefly COVID-19, caused by SARS-COV-2, is identified in Wuhan, China. It spread all over the world and became a pandemic. In many individuals who had suffered SARS-COV-2 infection, cytokine storm starts through cytokine overproduction and leads to Acute Respiratory Syndrome (ARS), organ failure, and death. According to the obtained evidence, Vitamin D (VitD) enhances the ACE2/Ang(1-7)/MasR pathway activity, and it also reduces cytokine storms and the ARS risk. Therefore, VitD intake may be beneficial for patients with SARS-COV-2 infection exposed to cytokine storm but do not suffer hypotension. In the present review, we have explained the effects of VitD on the renin-angiotensin system (RAS) function and angiotensin-converting enzyme2 (ACE2) expression. Furthermore, we have reviewed the biochemical and immunological effects of VitD on immune function in the underlying diseases and its role in the COVID-19 pandemic.

Mechanisms of COVID-19 Entry into the Cell: Potential Therapeutic Approaches Based on Virus Entry Inhibition in COVID-19 Patients with Underlying Diseases.

The Coronavirus disease 2019 (COVID-19) virus spread from Wuhan, China, in 2019 and is spreading rapidly around the world. COVID-19 victims are almost associated with cardiovascular disease, high blood pressure, diabetes, and other underlying diseases. Concerning the high prevalence of these disorders, widespread mortality threatens global society, and its fatality rate may increase with increasing COVID-19 prevalence in countries with older populations. Therefore, evaluating patients' clinical status with severe COVID-19 infection and their medical history can help manage treatment. Currently, one of the considered treatments is angiotensin-converting enzyme 2 (ACE2) inhibition. This study investigated virus entry mechanisms through membrane receptors, their role in the pathogenesis of COVID-19 and underlying diseases, and treatment methods based on the viral entrance inhibition. According to existing studies, inhibition of ACE2 can increase oxidative stress, inflammation, fibrosis and ultimately exacerbate underlying diseases such as cardiovascular disease, kidney disease, diabetes, and hypertension in individuals with COVID-19. The ACE2 inhibition is not suitable for patients with COVID-19 with underlying diseases, but it seems that the recombinant ACE2 solution is more appropriate for inhibiting the virus in these patients if hypotension would be monitored.