Avaliação da administração da vacina de febre amarela em pacientes com alergia a proteína do ovo em hospital de referência

Abstract

Introduction: Yellow fever (YF) is an acute febrile infectious disease transmitted by arthropod vectors, caused by a virus of the Flavivirus genus belonging to the Flaviviridae family. About About 50% of patients with hemorrhagic complications from yellow fever die, with no specific treatment available. The vaccine is contraindicated for people with severe egg allergies due to the risk of anaphylaxis. The available evidence on the administration and safety of the yellow fever vaccine in patients with egg allergies is limited.. To vaccinate children who did not receive the yellow fever vaccine during the 2017-2018 epidemic in Brazil, a vaccination plan was established at a referral center, including children with egg allergies Objectives: To describe the use of the YF vaccine and its adverse events in children with egg protein allergy in the absence of complex screening and desensitization protocols. Methods: Cross-sectional, analytical, quantitative study in a tertiary pediatric hospital from February 2018 to January 2020. Patients referred to the Food Allergy Clinic for supervised vaccination against YF were included in the study. The diagnosis of egg protein allergy was defined by the reproducible clinical history associated or not with evidence of allergic sensitization to egg proteins (punch test and/or serum IgE). Those with a history of anaphylactic reaction underwent a prick test with the pure vaccine. If positive test, vaccine applied in two doses of 0.25 ml subcutaneously (SC), 30 minutes apart and if negative test or history not compatible with food allergy, single dose of 0.5 ml SC of YF vaccine, followed by observation for 1 to 2 hours after vaccination. The primary outcome was defined as vaccine reaction and the analyzed predictor variables were clinical/laboratory characteristics of sex, age, history and severity of egg allergy, IgE Egg, IgE Egg White, IgE Albumin, IgE Ovomucoid, and Vaccine Punch Test. The study was approved by the Ethics Committee of FHEMIG and UFMG. Results: 435 egg-allergic children were evaluated; 82 (19%) were classified as probably not allergic and 353 (81%) as probably allergic to egg, of which 114/353 (32.3%) were considered to have severe egg allergy (anaphylaxis to egg). Only 21/114 (18.4%) received a fractionated dose. 414/435 (95.2%) patients had no vaccine reaction. Of the 21 (4.8%) patients who had some reaction to the vaccine, ten (47.62%) had a local reaction, nine (42.85%) had mild skin reaction distant from the vaccine site, one (4.76%) patient presented local and cutaneous reaction distant to the vaccination site and one patient (4.76%) developed a severe vaccine reaction (anaphylaxis) associated with local and distant cutaneous manifestations, which was treated with a single dose of epinephrine. None of the variables evaluated were associated with the presence of a vaccine reaction and the vaccine puncture test was negative in the patient with vaccine anaphylaxis. Vaccination in a single dose of 0.5 ml SC was indicated, and the test was not a predictor of vaccine reaction. Conclusion: Yellow fever vaccine can be safely administered in the absence of complex desensitization protocols, considering the low prevalence of vaccine reaction in patients with confirmed or suspected egg allergy. The presence of an equipped place and a trained professional to recognize and treat possible adverse reactions is necessary.