Andrea Toniato

Background: The increasing use of Magnetic Resonance Imaging (MRI) has led to a rise in the administration of gadolinium‐based contrast agents (GBCAs), accompanied by a growing number of reported adverse events (AEs).Objective: This review aims to provide an updated overview of hypersensitivity reactions (HSRs) to GBCAs, focusing on diagnostic and management strategies from an allergological perspective.Methods: We reviewed recent literature concerning the classification, clinical presentation, and pathophysiological mechanisms of HSRs to GBCAs. Particular attention was given to current recommendations for diagnosis, risk stratification, and prevention.Discussion: Adverse events to GBCAs are categorized into Type A reactions, which are dose‐dependent and predictable, and Type B reactions, which are dose‐independent hypersensitivity reactions. The latter may be allergic or non‐allergic, presenting diagnostic and therapeutic challenges.Conclusions: HSRs to GBCAs, though relatively rare, require careful evaluation and tailored management. An allergological work‐up, including skin testing and graded challenges when appropriate, plays a critical role in the safe re‐exposure of patients with prior reactions.

DRESS/DiHS is a complex and potentially fatal drug reaction. Little is known about risk factors and elements that can help to identify patients with a severe reaction early. The aim of the study was to investigate those factors favoring the disease and its severity by analyzing the clinical conditions and therapies preceding the reaction. We conducted a retrospective analysis on patients admitted to our center between 2010 and 2020 who were discharged with a diagnosis of DRESS. We used the RegiSCAR diagnostic criteria. We defined the severity of DRESS using the criteria of Mizukawa et al. We included 25 patients (15 females) with a median age of 66 years. Skin involvement, eosinophilia, and liver injury were the most important aspects. Allopurinol was found to be the most involved drug. Reaction severity was significantly associated with the number of daily medications (p = 0.0067) and an age of at least 68 years (p = 0.013). In addition, 75% of severe cases had at least three comorbidities in history, and most of the severe cases were female. In our study the advanced age, the high number of comorbidities and home therapies, and the inflammatory state were found to be predisposing elements to the development of the disease and its severity.

Introduction: Risk factors for systemic reactions (SRs) from hymenoptera venom (HV) allergy are well known in the adult population but they have been little studied in the pediatric one. Method: The aim of our study was to identify risk factors for SRs in a population of children allergic to HV, comparing a series of clinical (age, gender, atopy, asthma) and laboratory (total IgE, tryptase, venom-specific IgE levels) variables between patients with at least two large local reactions (LLRs) and patients with SRs of different severity for the identified insect. We selected a population of HV allergic children aged < 15 years with LLRs or SRs stratified according to Mueller grades after stinging. Results: The population included 80 children, 35 with at least 2 LLRs and 45 with SRs. The level of specific IgE for vespid (Polistes dominula, Vespula species) venoms was significantly higher (p = 0.0321) in children with SRs (Mueller grade II+III+IV) than in those with LLRs and the same significance was also found for specific IgE for Apis mellifera, considering SRs group (Mueller grade I+II+III+IV) in respect with LLRs group (p = 0.0001). Conclusion: The main difference in our pediatric population was the highest level of specific IgE in children with a history of SRs compared to those with a history of LLRs for both vespids and honey bees. These results, once confirmed on a larger population, could suggest the opportunity to follow the behavior of venom specific IgE in children with LLRs to reveal a risk to develop future more serious reactions.