LAUSR

Abstract Background Published data on coronavirus disease 2019 (COVID‐19) convalescent plasma (CCP) use in children and obstetric patients are limited. We describe a single‐center experience of hospitalized patients who received CCP for acute COVID‐19. Methods A retrospective review of children 0–18‐years‐old and pregnant patients hospitalized with laboratory‐confirmed acute COVID‐19 who received CCP from March 1, 2020 to March 1, 2021 was performed. Clinical and laboratory data were collected to assess the safety of CCP administration. Antibodies to severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) were measured in the CCP products and in patients before transfusion and at various time points post‐transfusion. Correlation between the administered SARS‐CoV‐2 administered versus the SARS‐CoV‐2 anti‐spike immunoglobulin response in patient serum was assessed. Results Twenty‐two children and ten obstetric patients were eligible. Twelve pediatric and eight obstetric patients had moderate disease and ten pediatric and two obstetric patients had severe disease. Five pediatric patients died. Eighteen of 37 (48.6%) CCP titers that were measured met US Food and Drug Administration (FDA) criteria for high immunoglobulin G (IgG) antibody titer. There were no complications with transfusion. High‐titer CCP showed a positive correlation with rise in patient total immunoglobulin levels only in obstetric patients but not in pediatric patients. Among pediatric patients, the median serum antibody level increased over time after transfusion. Conclusions Coronavirus 2019 convalescent plasma was administered safely to our patients. Our study suggested that CCP did not interfere with endogenous antibody production. The antibody titer of CCP correlated with post‐transfusion response only in obstetric patients. Randomized trials in pediatric and obstetric patients are needed to further understand how to dose CCP and evaluate efficacy.