The onset of late severe lung impairment in COVID-19 is associated with high inflammation markers at admission and metabolic syndrome markers (preprint)

Background: COVID-19 severity is mainly related to lung impairment. However, preexisting patient characteristics and biomarkers at admission associated with this event are not precisely known. Methods. We report 205 patients admitted for a proven COVID-19 in our institution between March 7 and April 22, 2020, particularly their comorbidities, respiratory severity, immune profile, and metabolic profile. Findings. Median age was 70 years [interquartile range (IQR) 25-75: 60;79]; 115 (56.1%) patients were men. Oxygen supplementation of >2L/min was required in 107 patients (52.2%) after a median time of 8 days [IQR: 6;10] after the first symptoms; 67 (32.7%) patients were admitted to the intensive care unit (ICU), almost exclusively due to severe hypoxia. Patients requiring >2L/min oxygen therapy and/or ICU admission were older and more frequently males, with a significantly higher body mass index (BMI), a significantly higher total cholesterol (TC) / HDL cholesterol ratio, and higher triglycerides. They also had higher plasma levels of C-reactive protein (CRP) and interleukin 6 (IL-6); IL-6 >20 ng/L and CRP >70 mg/L were significantly associated with ICU admission and/or (for patients with a decision of limitation of life-support therapy) death. Higher BMI and TC/HDL-c ratio were associated with higher CRP and IL-6 levels. Steroid therapy was performed in 61 patients; while its clinical impact was inconclusive due to heterogeneous situations, IL-6 levels decreased significantly more in these patients. Interpretation. Severe COVID-19 mostly relates to late-onset pneumonia associated with preexisting metabolic syndrome markers and a surge in inflammatory markers, allowing the early identification of at-risk patients.

Fine analysis of lymphocyte subpopulations in SARS-CoV-2 infected patients: toward a differential profiling of patients with severe outcome (preprint)

COVID-19 is caused by the human pathogen severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and has resulted in widespread morbidity and mortality. CD4+ T cells, CD8+ T cells and neutralizing antibodies all contribute to control SARS-CoV-2 infection. However, heterogeneity is a major factor in disease severity and in immune innate and adaptive responses to SARS-CoV-2. We performed a deep analysis by flow cytometry of lymphocyte populations of 125 hospitalized SARS-CoV-2 infected patients on the day of hospital admission. Five clusters of patients were identified using hierarchical classification on the basis of their immunophenotypic profile, with different mortality outcomes. Some characteristics were observed in all the clusters of patients, such as lymphopenia and an elevated level of effector CD8+CCR7- T cells. However, low levels of T cell activation are associated to a better disease outcome; on the other hand, profound CD8+ T-cell lymphopenia, a high level of CD4+ and CD8+ T-cell activation and a high level of CD8+ T-cell senescence are associated with a higher mortality outcome. Furthermore, a cluster of patient was characterized by high B-cell responses with an extremely high level of plasmablasts. Our study points out the prognostic value of lymphocyte parameters such as T-cell activation and senescence and strengthen the interest in treating the patients early in course of the disease with targeted immunomodulatory therapies based on the type of adaptive response of each patient.