Thymic Function in Patients With COVID-19

CMC Ambroise Paré85 enrolled

Overview

The main clinical manifestation associated with SARS-CoV-2 infection is an influenza-like illness that follows the infection of the respiratory tract. In a few percent of infected people, inflammation of the lungs leads to severe pneumonia that requires hospitalization, in intensive care units for the more severe cases. Despite intensive care, a fatal outcome occurs in 6% and 12% of women and men over 80 years of age hospitalized for severe COVID, respectively. Factors associated with a higher risk of death in patients with SARS-CoV-2 include age and low circulating lymphocyte counts. Significant lymphopenia is indeed frequently observed in patients with severe COVID-19 and both phenotypic and functional changes in antiviral T cells have been correlated with the severity of COVID-19. The thymus, the organ that produces T lymphocytes, undergoes progressive physiological involution with age. However, in the elderly, rare cases of thymic hyperplasia are reported in autoimmune diseases or cancers, or are observed in response to deep lymphopenia, whether or not associated with sepsis. This cohort of patients treated for a SARS-CoV-2 infection could allow to better understand the role of the thymus in this pathology.

Study Type

OBSERVATIONAL

Enrollment

Conditions

Covid19

Interventions

Single-Nucleotide Polymorphisms (SNP) within the TCRA/D region

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: Cases : * Patients with confirmed COVID-19 infection * Hospitalized for COVID-19 infection * Having signed a written informed consent form * Affiliation to the social security system Controls : * Non-COVID-19 patients * Hospitalized for other reasons * Age and sex-matched controls * Having signed a written informed consent form, * Affiliation to the social security system Exclusion Criteria: * Autoimmune disease * HIV, Hepatitis B or Hepatitis C * Pregnant or breastfeeding women * A mental or linguistic inability to understand the study * Patient under protection of the adults (guardianship, curators or safeguard of justice)

Outcomes

Primary Outcomes

Genetic Predisposition to severe forms of COVID-19

Test of association between single-nucleotide polymorphisms (SNP) within the TCRA/D region known to influence the level of thymopoiesis (Clave et al., Sci Transl Med., 2018) and CT scan classification of COVID-associated pneumopathy (0=Absent or minor pulmonary parenchymal changes ; 1=Limited ground-glass opacities ; 2=Bilateral ground-glass opacities \< 50% of pulmonary parenchyma ; 3=Idem 2, with superimposed inter/intra lobular septal thickening, i.e. 'crazy paving' ; 4=Bilateral ground-glass opacities \> 50% of pulmonary parenchyma ; 5=Idem 4, with superimposed 'crazy paving' ; 6=Idem 5, with pulmonary fibrosis).