SARS-CoV-2 in children with cancer or after haematopoietic stem cell transplant: An analysis of 131 patients.

Purpose: There are limited data on SARS-CoV-2 (COVID-19) infection in children with cancer or after haematopoietic stem cell transplant (HSCT). We describe the severity and outcomes of SARS-COV-2 in these patients and identify factors associated with severe disease.

Methods: This was a multinational, observational study of children (aged <19 years) with cancer or HSCT and SARS-CoV-2 confirmed by polymerase chain reaction. COVID-19 was classified as asymptomatic, mild, moderate, severe or critical (≥1 organ support). Exact polytomous regression was used to determine the relationship between clinical variables and disease severity.

Results: One hundred and thirty-one patients with COVID-19 across 10 countries were identified (median age 8 years). Seventy-eight (60%) had leukaemia/lymphoma, 48 (37%) had solid tumour and five had primary immunodeficiency and HSCT. Fever (71%), cough (47%) and coryza (29%) were the most frequent symptoms. The median duration of detectable virus was 16 days (range, 1-79 days). Forty-nine patients (37%) were hospitalised for COVID-19 symptoms, and 15 (11%) required intensive care unit-level care. Chemotherapy was delayed/modified in 35% of patients. COVID-19 was asymptomatic in 32% of patients, mild in 47%, moderate in 8%, severe in 4% and critical in 9%. In 124 patients (95%), a full recovery was documented, and four (3%) died due to COVID-19. Any comorbidity (odds ratio, 2.94; 95% confidence interval [CI], 1.81-5.21), any coinfection (1.74; 95% CI 1.03-3.03) and severe baseline neutropenia (1.82; 95% CI 1.13-3.09) were independently and significantly associated with increasing disease severity.

Conclusion: Although most children with cancer had asymptomatic/mild disease, 13% had severe COVID-19 and 3% died. Comorbidity, coinfection and neutropenia may increase the risk of severe disease. Our data may help management decisions in this vulnerable population.