COVID-19 Infection in Patients Undergoing Allogeneic Hematopoietic Stem Cell Transplantation

Introduction. The COVID-19 pandemic has changed the conditions for providing medical care to hematological patients, including those who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT). Objective: to analyze the course of the new coronavirus infection COVID-19 in patients who have undergone allo-HSCT. Materials and methods. The retrospective study included 87 patients who developed COVID-19 after allo-HSCT in the period from March 2020 to January 2022. In most cases, transplants were performed in patients with acute leukemia (77 %) using peripheral hematopoietic stem cells (52 %) or bone marrow (48 %) after conditioning in a reduced intensity mode (75 %). COVID-19 infection was considered confirmed when SARS-CoV-2 RNA was detected by PCR in a smear from the oropharyngeal/nasopharyngeal mucosa. Results. In 71 (81.6 %) patients, COVID-19 was established a year after performing allo-HSCT, in 16 (18.4 %) patients - during the first year after allo-HSCT. The median age at the time of the development of a new coronavirus infection was 42 years. At the time of the COVID-19 debut, 39 (45 %) patients received immunosuppressive therapy (IST). Performing IST at the time of diagnosis of COVID-19 had a negative effect on overall survival (p = 0.0001). A total of 7 (9 %) patients suffered from the disease asymptomatically, 39 (45 %) - in mild form, 23 (26 %) - in moderate, 10 (11 %) - in severe and 8 (9 %) - in critical form. TCR-alpha beta/CD19(+) graft depletion was associated with a milder course of COVID-19 infection in patients after allo-HSCT (p = 0.06). Hospitalization in a 24-hour hospital was required in 24 (27 %) cases. Conclusion. Overall survival was comparable in the general group of patients with allo-HSCT compared with healthy individuals with COVID-19, due to a sufficient degree of immune system reconstruction, as well as a small volume of the study group. The factors that increased the risk of an adverse outcome were age and male gender.