Factors that predict severity of infection and seroconversion in immunocompromised children and adolescents with COVID-19 infection.

Objectives: We aimed to study the outcomes, severity, and seroconversion post SARS-CoV-2 infection in immunocompromised children and adolescents treated at our center. Method: For this observational study, all pediatric patients who had COVID-19 infection from Sep-22-2020 to Nov-10-2021were identified by reviewing our laboratory records. Their charts were reviewed to determine clinical severity and outcome. Blood samples were drawn for anti-SARS-CoV-2 antibody assay. Serious COVID-19 infection (SVI) was defined if the patient had moderate, severe, or critical illness. A cutoff of 100 U/mL anti-SARS-CoV-2 antibodies was used to categorize low and high titer seroconversion. Results: We identified 263 pediatric patients with COVID-19; most (68%) were symptomatic: 5% had severe or critical infection, 25% were hospitalized, 12 required respiratory support, 12 were admitted to the ICU, and five patients (2%) died. Multivariable analysis revealed several factors that predict SVI: Age above 12 years (p=0.035), body mass index above 95 Conclusions: SARS-CoV-2 antibodies developed in most immunocompromised patients with COVID-19 infection in our study. Mortality was relatively low in our patients. Our univariable and multivariable models showed multiple variables that predict severity of infections and antibody response post COVID-19 infection. These observations may guide choice of active therapy during infection and the best timing of vaccination in this high-risk population.