Features of postinfectious immunity formation in a patient with common variable immune deficiency and severe COVID-19 course: a description of a clinical case

Background. Common variable immune deficiency (CVID) is a complicating comorbid background of COVID-19. Post-infectious immunity formation to SARS-CoV-2 during a pandemic is of particular relevance for such patients. Aim of the study - to present the features of the development of postinfectious humoral immune response in a patient with CVID. Material and methods. Patient K., 49 years old, the diagnosis of CVID verified at the age of 33, has been receiving regular replacement therapy with intravenous immunoglobulins for the last 10 years. After intrafamily contact and infection with SARS-CoV-2 due to the progressive deterioration of the clinical course of COVID-19, he was admitted to a monoinfection hospital. Results. During the treatment of the severe clinical case of COVID-19 a patient with CVID proved to be effective therapy combining anti-cytokine drugs and additional courses of replacement therapy with intravenous immunoglobulins. 6 weeks later from the development of the clinic, the patient was detected specific antibodies to SARS-CoV-2 antigens - IgM (CP 4.73) and IgG (43 BAU), in 4 months the corresponding parameters were 3.55 (CP IgM) and 487 BAU (CP IgG). Comparative analysis of immunophenotyping of the patient's B lymphocytes before the disease, during periods of early and late convalescence showed the dynamics of changes in the number of naive B-lymphocytes, unswitched and switched B-memory cells, plasmablasts, B-reg and B-lymphocytes expressing intercellular cooperation molecules. Conclusion. In the patient with CVID the development of a specific humoral immune response to SARS-CoV-2 after a COVID-19 infection is accompanied by an increase in the proportion of B-memory cells, increased maturation of B-lymphocytes, coordinated dynamics of B-cell suppression and activation parameters. Copyright © 2022 Authors. All rights reserved.