COVID-19 VACCINE REACTIONS AND SUSPECTED POLYETHYLENE GLYCOL ALLERGY: A PEDIATRIC CASE SERIES

INTRODUCTION: Studies have demonstrated tolerance in high risk patients receiving Covid-19 m-RNA vaccines containing polyethylene glycol (PEG) with rare reactions.There is limited pediatric data regarding safety in receiving PEG containing Covid-19 vaccines with a history of prior hypersensitivity reactions to PEG containing chemotherapy (PEG-CTX). METHODS: Retrospective chart review from referred Pediatric Oncology patients with a history of prior reactions to PEG-CTX (01/2020-04/2022). Selective skin testing was completed using PEG molecular weigh 3350 and m-RNA Covid-19 vaccines with controls. RESULTS: Four pediatric patients (≤18 years old) had evidence suggestive of an immediate, hypersensitive reaction to PEG-CTX following treatment for acute lymphoblastic leukemia (ALL). All 4 patients experienced prior reactions to chemotherapy (L-Asparaginase). Symptoms included: hypotension, flushing, urticaria, angioedema, emesis and tachycardia. Due to prior reactions, these high-risk patients were not administered PEG containing Covid-19 vaccines due to safety concerns. Non-PEG containing Covid-19 vaccines were not approved for use in pediatric patients. Allergy skin testing (skin prick and intradermal) was completed in all four patients. One of 4 patients tested positive to both PEG and PEG containing Covid-19 vaccine. The 3 negative patients were administered PEG containing Covid-19 vaccine with monitoring for one hour without symptoms. CONCLUSION: Pediatric patients in our study with prior reactions to PEG-CTX tolerated PEG containing Covid-19 vaccines. Further studies are needed in assessing PEG allergy in high-risk patients with a past history of reactions to PEG-CTX.