Serum soluble toll-like receptor 4 and risk for clinical severity in COVID-19 patients

Toll-like receptor 4 (TLR4) signaling mediates sustained systemic inflammation in(COVID)-19 patients. We aimed to assess the serum levels of sTLR4 and sCD14 as negative regulators of Toll like receptor signaling and their association with laboratory markers and clinical severity in covid 19 patients. Ninety-eight patients with COVID-19 (70 severe and 28 non-severe) were enrolled in the study. Serum sCD14 andsTLR4were determined by ELISA. A significant increase in serum sTLR4 and sCD14 levels was detected in severe compared to non severe COVID19 patients.Receiver operating characteristic curve (ROC) analysis revealed significant diagnostic potential of serum sTLR4 and sCD14 in covid19 patients.We conclude that Serum sTLR4 and sCD14 may be promising clinical severity markers for COVID19 patients.

Immunological changes in a cohort of COVID-19 survivors: Mansoura University experience

Background: COVID-19 is a global pandemic that has affected millions of people all over the world since 2019. Infection with COVID-19 initiates a humoral immune response that produces antibodies against specific viral antigens, which in turn is supposed to provide immunity against reinfection for a period of time. The aim of this research was to study the kinetics of IgM and IgG antibodies against SARS-CoV-2. Methods: One hundred and seventeen post-COVID-19 participants were enrolled in the study.  Qualitative assessment of IgM and IgG antibodies over six months (three visits) post recovery was conducted. Results: The current study revealed a significant reduction in IgM and IgG titers between the first and second visits (p <0.001). After six months, the antibody titer had declined by 78.8% from the first visit for IgM and by 49.2% for IgG antibodies. Regarding younger age and male sex, statistically significant persistence of IgM antibodies was noticed at the six months follow up. Also, statistically significant persistent IgG immunity was found in male patients and diabetics by the end of the six months follow up. Conclusions: We observed a significant waning of IgM and IgG titers over a period of six months follow up.. The persistence of positive IgM and IgG antibodies by the end of six months was variable due to differences in age, gender and presence of diabetes mellitus.

Characterization of regulatory T cells in SARS-CoV-2 infected hemodialysis patients: relation to clinical and radiological severity

BACKGROUND

Disordered Treg counts and function have been observed in patients with SARS-Cov-2 and are thought to contribute to disease severity. In hemodialysis patients, scarce data are available on the Treg response to SARS-CoV-2 or its relation to the clinical presentation.

METHODS

A cross-sectional study included one hundred patients divided into three groups, thirty SARS-CoV-2-infected hemodialysis patients (COV-HD), and thirty confirmed SARSCoV-2 infected patients (COV), and forty non-infected hemodialysis patients (HD). Flow cytometric analysis of CD4, CD25, FoxP3, and CD39+ Tregs was done for all patients and tested for correlation to in-hospital mortality, clinical, radiological severity indices.

RESULTS

COV-HD and COV patients had significantly lower Treg cell count than HD patients (Median value of 0.016 cell/ μl vs 0.28 cell/ μl, respectively- P: 0.001). COV-HD patients had higher CD39+ Tregs (median value of 0.006 cell/ μl vs 0.002 cell/ μl, respectively- P: 0.04). COV-HD patients had significantly lower hospital stay (median value of 3 vs 13 days, P:0.001), ICU admission rates (26.5% vs 46.7%, P:0.005) and in-hospital mortality (20.7% versus 43.3%, P:0.003) than COV patients. Treg and CD39 expressing Treg counts were not correlated to severity indices in both groups. A high neutrophil to lymphocyte ratio is strongly correlated to disease severity in COV-HD patients.

CONCLUSIONS

This study provides evidence of T-cell, particularly T-regulatory cell decline in SARS-CoV-2 and suggests that hemodialysis per se does not distinctively impact the T-cell response. COV-HD patients exhibited a higher CD39+ Treg count and a better clinical profile, however, larger studies are needed to extrapolate on these findings.

Screening of latent TB infection in patients with recently diagnosed bronchogenic carcinoma

BACKGROUND

Cancer and pulmonary tuberculosis are major global health concerns and are associated with substantial morbidity and mortality. The association between active tuberculosis and subsequent cancer development has been investigated for many years. This study was planned to determine the prevalence of latent tuberculosis infection in patients with recently diagnosed bronchogenic carcinoma.

METHODS

Sixty-four newly diagnosed primary lung cancer patients were enrolled. Diagnosis of latent tuberculosis infection was performed with QuantiFERON-TB Gold In-Tube tests, with exclusion of active tuberculosis.

RESULTS

Latent tuberculosis infection was detected in 16 (25%) patients, and 8 (12.5%) had indeterminate results of the QuantiFERON-TB Gold In-Tube test. Being a current smoker was associated with a higher prevalence of latent tuberculosis (p = 0.001). Comorbidities, tumor site, and histopathology were not associated with latent tuberculosis infection.

CONCLUSIONS

There is a considerable risk of concurrent latent tuberculosis in newly diagnosed primary bronchogenic carcinoma. The need for treatment of latent tuberculosis in these patients and its influence on the outcome and prognosis are issues for further investigations.