Biomarkers for severe COVID-19

COVID-19: Recent Insight in Genomic Feature, Pathogenesis, Immunological Biomarkers, Treatment Options and Clinical Updates on SARS-CoV-2

SARS-CoV-2 is a highly contagious and transmissible viral infection that first emerged in 2019 and since then has sparked an epidemic of severe respiratory problems identified as "coronavirus disease 2019" (COVID-19) that causes a hazard to human life and safety. The virus developed mainly from bats. The current epidemic has presented a significant warning to life across the world by showing mutation. There are different tests available for testing Coronavirus, and RT-PCR is the best, giving more accurate results, but it is also time-consuming. There are different options available for treating n-CoV-19, which include medications such as Remdesivir, corticosteroids, plasma therapy, Dexamethasone therapy, etc. The development of vaccines such as BNT126b2, ChAdOX1, mRNA-1273 and BBIBP-CorV has provided great relief in dealing with the virus as they decreased the mortality rate. BNT126b2 and ChAdOX1 are two n-CoV vaccines found to be most effective in controlling the spread of infection. In the future, nanotechnology-based vaccines and immune engineering techniques can be helpful for further research on Coronavirus and treatment of this deadly virus. The existing knowledge about the existence of SARS-CoV-2, along with its variants, is summarized in this review. This review, based on recently published findings, presents the core genetics of COVID-19, including heritable characteristics, pathogenesis, immunological biomarkers, treatment options and clinical updates on the virus, along with patents.

Utility of laboratory and immune biomarkers in predicting disease progression and mortality among patients with moderate to severe COVID-19 disease at a Philippine tertiary hospital

Purpose

This study was performed to determine the clinical biomarkers and cytokines that may be associated with disease progression and in-hospital mortality in a cohort of hospitalized patients with RT-PCR confirmed moderate to severe COVID-19 infection from October 2020 to September 2021, during the first wave of COVID-19 pandemic before the advent of vaccination.

Patients and methods

Clinical profile was obtained from the medical records. Laboratory parameters (complete blood count [CBC], albumin, LDH, CRP, ferritin, D-dimer, and procalcitonin) and serum concentrations of cytokines (IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-18, IFN-γ, IP-10, TNF-α) were measured on Days 0-3, 4-10, 11-14 and beyond Day 14 from the onset of illness. Regression analysis was done to determine the association of the clinical laboratory biomarkers and cytokines with the primary outcomes of disease progression and mortality. ROC curves were generated to determine the predictive performance of the cytokines.

Results

We included 400 hospitalized patients with COVID-19 infection, 69% had severe to critical COVID-19 on admission. Disease progression occurred in 139 (35%) patients, while 18% of the total cohort died (73 out of 400). High D-dimer >1 µg/mL (RR 3.5 95%CI 1.83-6.69), elevated LDH >359.5 U/L (RR 1.85 95%CI 1.05-3.25), lymphopenia (RR 1.91 95%CI 1.14-3.19), and hypoalbuminemia (RR 2.67, 95%CI 1.05-6.78) were significantly associated with disease progression. High D-dimer (RR 3.95, 95%CI 1.62-9.61) and high LDH (RR 5.43, 95%CI 2.39-12.37) were also significantly associated with increased risk of in-hospital mortality. Nonsurvivors had significantly higher IP-10 levels at 0 to 3, 4 to 10, and 11 to 14 days from illness onset (p<0.01), IL-6 levels at 0 to 3 days of illness (p=0.03) and IL-18 levels at days 11-14 of illness (p<0.001) compared to survivors. IP-10 had the best predictive performance for disease progression at days 0-3 (AUC 0.81, 95%CI: 0.68-0.95), followed by IL-6 at 11-14 days of illness (AUC 0.67, 95%CI: 0.61-0.73). IP-10 predicted mortality at 11-14 days of illness (AUC 0.77, 95%CI: 0.70-0.84), and IL-6 beyond 14 days of illness (AUC 0.75, 95%CI: 0.68-0.82).

Conclusion

Elevated D-dimer, elevated LDH, lymphopenia and hypoalbuminemia are prognostic markers of disease progression. High IP-10 and IL-6 within the 14 days of illness herald disease progression. Additionally, elevated D-dimer and LDH, high IP-10, IL-6 and IL-18 were also associated with mortality. Timely utilization of these biomarkers can guide clinical monitoring and management decisions for COVID-19 patients in the Philippines.

Evaluation of a potential prognostic parameter for the inflammatory status in COVID‐19 patients: The inflammatory protein ratio

C‐reactive protein (CRP), fibrinogen, and d‐dimer are determined in the human plasma of 2745 hospitalized patients with and without coronavirus disease 2019 (COVID‐19) by automated‐latex enhanced immunoassay and immuno‐turbidimetric assay. SARS‐COV‐2 RNA qualitative test, real time polymerase chain reaction (RT‐PCR) based, is performed in nasopharyngeal swabs to confirm those with SARS‐COV‐2 positivity. Furthermore, serum proteins are separated and quantified in all the patients by serum protein electrophoresis (SPE).

A new SPE parameter, inflammatory protein ratio (IPR), is elaborated for the first time by a mathematical equation that considers the albumin, α1‐globulin, and α2‐globulin. IPR normal reference range (10.7%–28.3%) is calculated considering the normal reference range of albumin, α1‐globulin, and α2‐globulin obtained for controls. Analysis of variance (ANOVA), Pearson's, Kruskal–Wallis, and Spearman's tests application show that IPR significantly correlates with direct proportionality with d‐dimer, CRP, and fibrinogen. Significant (p < 0.001) increase of these parameters, IPR included, is detected in COVID‐19 patients only. Our results show that IPR is more specific for monitoring inflammatory status thanks to its correlation with the only three serum proteins involved in inflammation: albumin, α1‐globulin, and α2‐globulin. Furthermore, IPR can simplify the interpretation of SPE results about inflammatory status, being of unique value compared to the six‐serum protein classes separately presented in the typical SPE clinical reports.

Effectiveness of Tocilizumab in Patients with Severe or Critical Lung Involvement in COVID-19: A Retrospective Study

Introduction: Acute lung injury is associated with dysfunctional immune response to SARS-CoV-2. This leads to CRS, which require immunomodulatory treatments aiming to limit the excessive production of cytokines. The literature so far indicates the effectiveness of tocilizumab in patients with COVID-19-associated pneumonia, but there is no clear evidence of its effectiveness in patients with at least 50% lung involvement; therefore, we aimed to bridge this gap in knowledge. Materials and methods: Longitudinal data for 4287 patients with confirmed COVID-19 infection were collected between 1st March 2020 and 16th of January 2022. In total, 182 cases with lung involvement >50% and biochemical indicators of cytokine release storm (Il-6 >100 pg/mL) were selected and analyzed using non-parametric statistics and multivariate Cox models. Results: Among the 182 included patients, 100 (55%) were treated with TCZ, while 82 (45%) did not receive TCZ. The groups were balanced regarding demographics, lung involvement and biochemical markers. Overall mortality in the group was 63.1%. Mortality in the TCZ group was 58.0% compared to 69.5% (n = 57) in the non-TCZ group (p = 0.023). In multivariate Cox proportional hazards models, intravenous administration of tocilizumab was associated with lower probability of ICU admission (HR: 0333 (CI: 0.159−0.700, p = 0.004)) and lower mortality (HR: 0.57306 (CI: 0.354−0.927, p = 0.023)). Conclusions: Tocilizumab is effective as a treatment in the most severely ill patients, in whom the level of lung involvement by the inflammatory process can exceed 50% with coexisting biochemical indices of cytokine storm (Il-6 > 100 pg/mL).

Free Zinc as a Predictive Marker for COVID-19 Mortality Risk

Free zinc is considered to be the exchangeable and biological active form of zinc in serum, and is discussed to be a suitable biomarker for alterations in body zinc homeostasis and related diseases. Given that coronavirus disease 2019 (COVID-19) is characterized by a marked decrease in total serum zinc, and clinical data indicate that zinc status impacts the susceptibility and severity of the infection, we hypothesized that free zinc in serum might be altered in response to SARS-CoV-2 infection and may reflect disease severity. To test this hypothesis, free zinc concentrations in serum samples of survivors and nonsurvivors of COVID-19 were analyzed by fluorometric microassay. Similar to the reported total serum zinc deficit measured by total reflection X-ray fluorescence, free serum zinc in COVID-19 patients was considerably lower than that in control subjects, and surviving patients displayed significantly higher levels of free zinc than those of nonsurvivors (mean ± SD; 0.4 ± 0.2 nM vs. 0.2 ± 0.1 nM; p = 0.0004). In contrast to recovering total zinc concentrations (r = 0.706, p < 0.001) or the declining copper−zinc ratio (r = −0.646; p < 0.001), free zinc concentrations remained unaltered with time in COVID-19 nonsurvivors. Free serum zinc concentrations were particularly low in male as compared to female patients (mean ± SD; 0.4 ± 0.2 nM vs. 0.2 ± 0.1 nM; p = 0.0003). This is of particular interest, as the male sex is described as a risk factor for severe COVID-19. Overall, results indicate that depressed free serum zinc levels are associated with increased risk of death in COVID-19, suggesting that free zinc may serve as a novel prognostic marker for the severity and course of COVID-19.