Abstract
How to cite this article: Gajjala C, Jindal, A. COVID-19 and T Cells: Do T Cells Really Matter? Indian J Crit Care Med 2023;27(1):75.
Keywords: Coronavirus disease-2019, Lymphopenia, T cells
Dear Editor,
We read with utmost interest the article titled “Characteristics and Predictive Value of T-lymphocyte Subset Absolute Counts in Patients with coronavirus disease-2019 (COVID-19)-associated Acute Respiratory Failure: A Retrospective Study” by Vadi et al.1 We appreciate the authors for their research work, but we would like to express our views about this.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel virus that causes COVID-19 infection, has recently emerged as a deadly pandemic and a higher mortality rate in older adults with comorbidities such as hypertension, cardiovascular disease, diabetes, chronic respiratory disease, and chronic kidney disease. The authors have included patients with SARS-CoV-2 in the COVID ICU with acute respiratory failure but have not mentioned the criteria for acute respiratory based on noninvasive and invasive ventilation. Most importantly corticosteroids have an effect on white blood and absolute lymphocyte count, and the authors did not mention clearly about the type, doses, and duration of corticosteroids, which itself lead to altered counts rather than due to COVID infection.2 Patients on chemotherapy, radiation, and infections like viral hepatitis, HIV, and tuberculosis will have lymphopenia so including these patients leads to bias in the study.3 Patients were classified into severe and nonsevere groups based on oxygen requirement and compared counts between the groups, but they excluded patients without severe acute respiratory infection. Most of the patients included were above 50 years, as age progresses T cells counts differ causing the ineffective response to infection so it is difficult to comment on the counts predisposing to severe infection in older patients.4 To add more power to the study, baseline characteristics and diabetic patients should have been better compared by doing subgroup analysis between severe and nonsevere groups based on counts.
Orcid
Chandana Gajjala https://orcid.org/0000-0003-0708-2603
Atul Jindal https://orcid.org/0000-0002-0504-1077
Footnotes
Source of support: Nil
Conflict of interest: None
References
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