D3.269 - Drug-Induced Anaphylaxis in Children: A Comparative Analysis of Inpatient vs. Outpatient Settings

Studies specifically focusing on drug-induced anaphylaxis (DIA) in children are few. Furthermore, there is no study comparing inpatient (IP) and outpatient (OP) settings in DIA, either in children or in adults. This study aimed to compare the characteristics of pediatric DIAs observed in IP and OP settings. 

Patients aged ≤18 years who were diagnosed with DIA at our institution over the past 15 years were included in the study. The diagnosis of DIA was made clinically, and diagnostic tests (skin and/or provocation tests) were performed in eligible patients. Patients with DIA in hospital wards or intensive care units were categorized as the IP group, while those with DIA at home, outpatient facilities, or emergency departments were categorized as the OP group.

A total of 162 pediatric DIA cases with a median age at diagnosis of 87.5 months were reviewed, including 55% in IP settings and 45% in OP settings. The most frequent trigger drugs were chemotherapeutics, enzymes, and antibiotics in IP group, and NSAIDs, antibiotics, and local anesthetics in OP group. The use of parenteral drugs were more frequent in IP vs OP group (97.7% vs 47.9%, p< 0.001). Age at DIA onset, time to DIA, and severity of DIA were similar in both groups. After excluding parenteral drugs from the OP group, significant differences in all three parameters were seen in IP vs. OP group (p<0.05 for each). 

Patients in the IP group had a higher prevalence of non-allergic chronic comorbidities and more frequent gastrointestinal symptoms (p≤0.001 for each). The OP group exhibited higher rates of asthma and allergic rhinitis, more frequent acute infections as co-factor (p<0.001 for each). Patients in OP group showed greater use of antihistamines and systemic corticosteroids (p<0.05 for each), while the use of IM adrenaline in DIA management was consistent across both groups.

Triggers, chronic comorbidities, and co-factors in pediatric DIA differ between IP and OP settings. Contrary to expectations, the settings did not impact the time of onset or severity of DIA, likely due to the higher frequency of parenteral drug administration in the OP settings.