Background Beta-lactams generate different allergenic determinants that
induce selective or cross-reactive drug hypersensitivity reactions
(DHRs). We aimed to identify the drugs involved, the selectivity of the
response, the mechanism, and the value of the different diagnostic tests
for establishing a diagnosis in children evaluated for DHRs to
beta-lactams. Methods Prospective study evaluating children aged under
16 years reporting DHRs to beta-lactams. Reactions were classified as
immediate and nonimmediate reactions. The work-up included sIgE, skin
testing and drug provocation tests (DPTs) for immediate reactions and
patch testing and DPTs for nonimmediate ones. Results Of the 510
included children, 133 were evaluated for immediate reactions and
confirmed in 8.3%. Skin test/in vitro IgE contributed to diagnosing
half of the cases. Selective reactions occurred with amoxicillin (63%),
followed by common penicillin determinants (27%) and cephalosporins
(0.9%). Among nonimmediate reactions (11,4% of the 377 children
evaluated), most required DPTs, 52.7% of which were positive at 6–7
days of drug challenge. Selective reactions were identified with
amoxicillin (80%), penicillin G (7.5%), cephalosporins (7.5%), and
clavulanic acid (5%). Urticaria and maculopapular exanthema were the
most frequent entities. Conclusions There were few confirmed cases of
either type of reaction. Skin testing proved less valuable in
nonimmediate reactions, over half of which would also have been lost in
a short DPT protocol. Selective responders to amoxicillin were more
likely to have nonimmediate reactions, while clavulanic acid-selectivity
was exclusive to the nonimmediate typology. Over half the cases with
DPTs required 6-7 days of treatment for DHR confirmation.
Patterns of response and drugs involved in hypersensitivity reactions to beta‐lactams in children
