Methods: From June 2011 to June 2014, a prospective observational study was implemented in 5 allergology units from different regions of Brazil. Children and adolescents reporting DHR were evaluated using a modified ENDA questionnaire, and a standardized diagnostic work up was performed.
Results: One hundred sixty-seven patients were evaluated, 93 male, with a median age of 10 years. Personal history of atopy was reported in 113 and previous DHR in 33. Cutaneous manifestations were observed in 157: urticaria and/or angioedema (115); macular or maculopapular exanthema (39); fixed drug eruption (1); Stevens-Johnson Syndrome (1) and acute generalized exanthematous pustulosis (1). Other symptoms reported were: respiratory (41), gastrointestinal (15), cardiovascular (8). The interval between dose and reaction was less than 1 hour in 92 subjects. Mild reaction was observed in 59 patients and moderate in 96. Fever and/or viral infection were present in 104 patients during or just before the reaction. The majority of subjects were treated in emergency units (143). The most frequent drugs involved were NSAIDs in 47% and beta-lactam antibiotics in 38%. More than one drug was suspected as a trigger in 90 children. Skin tests (prick and intradermal) were performed in 26 patients: 25 were negative (penicillin 15, amoxicillin 2, ceftriaxone 2, lidocaine 6) and one was positive (cefazoline). Drug provocation tests were positive in 12 of 92 patients: NSAIDs 48 (11 positive), beta-lactam antibiotics 35 (1 positive), local anesthesics 6 and others 3. One hundred and ten reactions were possible or probable related with the suspected drug, but in 44 this relation was unlikely.
Conclusions: Children and adolescents with a suspected history must be fully investigated to confirm or exclude the diagnosis of DHR.