The clinical course of the novel coronavirus disease in children after allogeneic hematopoietic stem cell transplantation

Abstract

The clinical course of the novel coronavirus disease (COVID-19) in patients with oncological and hematological diseases after hematopoietic stem cell transplantation (HSCT), are of special interest. To further investigate the problem, a two-center study was undertaken at the Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology and the R.M. Gorbacheva National Research Institute for Pediatric Oncology, Hematology and Transplantation between January 2020 and January 2023. This was a retrospective-prospective, non-randomized, non-interventional study that included children aged 0–19 years with oncological and hematological diseases and primary immunodeficiencies who had undergone allogeneic HSCT and subsequently contracted COVID-19. The study was approved by the Independent Ethics Committee and the Scientific Council of the Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology. COVID-19 cases were confirmed by polymerase chain reaction testing and classified as asymptomatic, mild, moderate, severe, and critical. The study included 105 patients with a median age of 9 years; male patients were predominant (the male-to-female ratio was 1.8:1). The primary diseases were hematological malignancies (73%), benign hematological diseases (14%) and primary immunodeficiencies (13%). The most common clinical symptoms of COVID-19 were fever, gastrointestinal symptoms, and respiratory symptoms; 40% of COVID-19 cases were asymptomatic. Lymphopenia was found to be a risk factor for severe COVID-19. The patients without immune reconstitution had a longer persistence of the COVID-19 virus than those with immune reconstitution (17 days versus 13 days), however, no significant differences were obtained (p = 0.7). There were also no significant differences in the severity and outcomes of COVID-19 between the patients with immune reconstitution and those without reconstitution. There was no effect of therapy on the duration of COVID-19, and there was no association between the type of treatment and the duration of the disease. The overall survival rate in the allo-HSCT recipients who had been diagnosed with COVID-19 was 88%, which was lower than in the non-recipients (88% vs 94%; p = 0,077).