Is an extensive allergy diagnosis workup needed in all cases of suspected hypersensitivity to beta-lactams in children?

Results Eighty children (56.2% females) with a mean age of 6.7 yrs (SD=4.035) where evaluated for 83 suspected BL HSR. The mean time elapsed between the reaction and the clinical assessment was of 3.1 yrs (SD=3.36). The most frequently implicated drugs were amoxicillin/ clavulanate (54.2%) and amoxicillin (32.5%). BL were prescribed for tonsillitis in 32.5%, otitis in 21.7% and upper airways infection in 19.3%. Cutaneous lesions were the most frequently reported (94%) manifestations, with maculopapular exanthema (MPE) being the most common. In 45 reactions (54.2%), the time of onset was unknown; in 4.8% the reaction was immediate and in the remaining cases non immediate (41%). In 23 cases (27.7%) there was no history of previous exposure to the suspected drug; 15 children had previous exposure with a similar reaction. In the group of patients with immediate reactions or unknown time of onset (n=49), determination of specific IgE (sIgE) for penicillin G, V and amoxicillin was performed in 43 (87.8%), and skin prick tests in 42 patients (85.7%), all with negative results. Of all patients, 16 (20%) underwent intradermal testing (IDT) and only one patient had a positive result with PPL 1/1; late reading was done in 3 cases, all negative. Oral provocation test (OPT) with the suspected BL (single or continued at home) was performed in 74 cases (89.2%) with positive result in 6 patients (8.1%), all of them exclusively with late cutaneous involvement.