1 - Serviço de Imunoalergologia, Centro Hospitalar Universitário de Lisboa Central, Lisboa
2 - Centro Clínico Académico de Lisboa
3 - Comprehensive Health Research Center (CHRC), NOVA Medical School, Universidade Nova de Lisboa, Lisboa, Portugal
- Comunicação oral em reunião internacional – World Allergy Congress, Lisboa, setembro de 2024
Background: Suspected beta-lactam (BL) hypersensitivity (HS) is a common problem in pediatric patients, although confirmed hypersensitivity is rare at this age. Our aim was to characterize the pediatric patients evaluated in our department due to a BL HS suspicion during a five-year period and to study differences between the group of children who underwent skin testing (ST) as the first step in diagnosis (followed by drug provocation testing (DPT)) and the group who underwent DPT alone.
Material and methods: Retrospective study including all pediatric patients evaluated for beta-lactam hypersensitivity between 2015 and 2019. Clinical and demographic data were collected and analysed. Reactions to beta-lactams were classified as immediate (IR)/non-immediate (NIR)/unknown timing (U) and the patients as high (H-Rp)/low-risk patients (L-Rp), according to the most recent EAACI guidelines.
Results: We included 341 patients, mean age 6.2 + 4.7 years old, 187 males; 252 (Group 1) underwent a direct DPT and 89 performed ST before DPT (Group 2). In Group 1, the mean patients’ age was lower (4.6 +3.7 vs 10.8 + 4.1 years; p<0.001), with fewer IR (15.5 vs 34.8%; p<0.001) and females (41.7 vs 55.1%; p=0.035). H-Rp were more common in group 2 (40.4% vs 20.6%; p<0.001). DPT was positive in 13 (5.2%) patients in group 1: 3 IR, 8 NIR and 2 U on index reaction. Four were H-Rp and 9 L-Rp. Most of the group 1 patients’ (236; 93,7%) were challenged with the culprit drug, which was positive in 13 (5,5%); 16 took an alternative BL (all negative). There was no anaphylaxis during DPT. In group 2, ST was positive in 7 cases (7.9%): 5 IR (1 anaphylaxis), 1 NIR and 1 U upon index reaction. All were H-Rp. There were no generalized reactions upon ST. Of these 7 patients, only 4 performed DPT with an alternative BL (negative in 3 and inconclusive in 1 case). Of those with negative ST (n=82, 92.1%), 69 underwent DPT, 46 with the culprit drug (4 positive – 8,7%; one classified as H-Rp) and 23 with an alternative BL (all negative). Of the 88 patients classified as H-Rp, 12 (13.6%) had a confirmed diagnosis vs 12 (4.7%) of the 253 L-Rp (p=0.032).
Conclusions: Beta-lactam hypersensitivity was confirmed in 24 patients, 7.3% of those who completed the investigation (n=328). High risk was associated with positive HS to BL.
Palavras-Chave: alergia medicamentosa, imunoalergologia pediátrica, testes cutâneos