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Published on: September 30, 2014
Direct oral provocation test with beta-lactams in Brazilian children and adolescents
Nathália Mota Gomes de Almeida1, Mara Morelo Rocha Felix2, Maria Inês Perelló Lopes Ferreira3
1Universidade do Estado do Rio de Janeiro (UERJ), Ciências Médicas, Rio de Janeiro, Brazil.
Objective:
Beta-lactam (BL) allergy is considered a public health issue worldwide. To date, there is no consistent data on the direct Oral Provocation Test (OPT) for BL in Brazilian children and adolescents. This study's main objective is to describe the safety profile of direct OPT in this population.
Method:
A cross-sectional study was conducted with patients aged 1 to 17 years with a history of mild immediate or delayed reactions to penicillin. The European Network of Drug Allergy (ENDA) questionnaire was used. The authors performed OPTs with amoxicillin over five days. Continuous variables were described using their means and standard deviations. Bivariate analysis between test positivity and other study variables was performed using the Chi-square test, odds ratio, and their respective 95 % confidence intervals (CI 95 %). A p-value < 0.05 was considered significant.
Results:
In total, 54 OPTs were performed, four were positive (7.5 %) and one was considered inconclusive. All reactors were boys and had delayed reactions, with no severe reactions, and three showed symptoms on the first day of testing.
Conclusion:
>90 % of the sample was delabeled as allergic to BL. There were no severe reactions, confirming the safety of direct OPT in this age group. Among the reactors, 3 patients presented symptoms on the first day of testing before receiving the second dose and one had symptoms on 5 days, indicating that further studies are needed on the optimal duration of the OPT.
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