ABSTRACT
BACKGROUND: By the end of 2019, the COVID-19 pandemic spread all around the world with a wide spectrum of clinical presentations ranging from mild to moderate to severe or critical cases. T cell subtype dysregulation is mostly involved in the immunopathogenic mechanism. The present study aimed to highlight the role of monitoring T cell subtypes and their activation (expression of CD38) in COVID-19 patients compared to healthy subjects and their role in predicting severity and patients' outcomes. MATERIALS: The study involved 70 adult COVID-19 confirmed cases stratified into three groups: a mild/asymptomatic group, a clinically moderate group, and a clinically severe/critical group. Flow cytometry analysis was used for the assessment of CD3+ cells for total T cell count, CD4+ cells for helper T cells (Th), CD8+ cells for cytotoxic T cells (Tc), CD4+CD25+ cells for regulatory T cells (T reg), and CD38 expression in CD4+ T cells and CD8+ T cells for T cell activation. RESULTS: A statistically significant difference was found between COVID-19 cases and healthy controls as regards low counts of all the targeted T cell subtypes, with the lowest counts detected among patients of the severe/critical group. Furthermore, CD38 overexpression was observed in both CD4+ and CD8+ T cells. CONCLUSION: Decreased T cell count, specifically CD8+ T cell (Tc), with T cell overactivation which was indicated by CD38 overexpression on CD4+ and CD8+ T cells had a substantial prognostic role in predicting severity and mortality among COVID-19 patients. These findings can provide a preliminary tool for clinicians to identify high-risk patients requiring vigilant monitoring, customized supportive therapy, or ICU admission. Studies on larger patient groups are needed.
ABSTRACT
There have been multiple reports of patients with coronavirus disease (COVID-19) testing positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) after discharge; however, information on the characteristics of such cases is limited. In this case report, we aimed to identify clinical and epidemiological characteristics of patients who had a repeat positive polymerase chain reaction (PCR) test for SARS-CoV-2. We analyzed data of 22 COVID-19 patients who tested positive for SARS-CoV-2 on polymerase chain reaction (PCR) testing after two consecutive negative PCR results following discharge from hospitals. The interval between the two positive tests in the episodes of COVID-19 ranged from 4 to 117 days. More than one-third of the cases were healthcare workers (HCWs) and one-third of them had comorbidities. The main symptoms were cough and fever, and we noticed that males experienced more symptoms and signs of COVID-19 than females. Individuals with repeat SARS-CoV-2 positivity tend to experience milder illness during the second episode than the first episode. To confirm the reinfection of SARS-CoV-2, the results of other tests, such as viral culture and immunological assays of immunoglobulin G (IgG) and immunoglobulin M (IgM), need to be considered. Recovered COVID-19 patients should continue social distancing, using face masks, and practicing hand hygiene, especially HCWs who are more likely to be exposed to SARS-CoV-2.