Symmetrical drug-related intertriginous and flexural exanthema: A little-known drug allergy

Very rare adverse reactions to intravascular contrast media: From Kounis to sweet syndrome

Intravascular administration of contrast media may inadvertently result in adverse drug reactions (ADR) including selected hypersensitivity reactions. This review highlights some very rare ADR, aiming to alert imaging physicians to these conditions and to prompt adequate management. This is particularly relevant for Kounis syndrome, an immediate hypersensitivity reaction involving the coronary arteries. The acute management of Kounis syndrome can be challenging, as it requires continued contrast media administration, while balancing the simultaneous coronary reperfusion that requires vasodilatation with anti-allergic treatment that may involve vasoconstrictor agents. For other adverse reactions, referral to a drug allergy specialist is highly recommended to assess causality and identify safe alternatives. CLINICAL RELEVANCE STATEMENT: Cardiologists and radiologists must recognize the key symptoms of these very rare adverse reactions to contrast media to promptly initiate the appropriate therapy and refer patients for allergological evaluation, ideally within 1-6 months after the reaction.

Acute generalized exanthematous pustulosis: European expert consensus for diagnosis and management

Acute generalized exanthematous pustulosis (AGEP) is a rare, usually drug-induced, acute pustular rash. Despite the lack of strong data supporting the effectiveness of topical or systemic corticosteroids in this drug reaction, they are widely used. More generally, there is no consensus on the diagnostic modalities and the management of patients with AGEP. We aimed to provide European expert recommendations for the diagnosis and management or patients with AGEP. Members of the ToxiTEN group of the European Reference Network (ERN)-skin, all dermatologists and/or allergologists with expertise in drug reactions, elaborated these recommendations based on their own experience and on a review of the literature. Recommendations were separated into the following categories: professionals involved, assessment of the diagnosis of AGEP, management of the patient and allergological work-up after the acute phase. Consensus was obtained among experts for the list of professionals involved for the diagnosis and management of AGEP, including the minimum diagnostic work-up, the setting of management, the treatments, the modalities and the timing of allergological work-up and follow-up. European experts in drug allergies propose herein consensus on the diagnosis and management of patients with AGEP. A multidisciplinary approach is warranted, including dermatologists, allergologists and pharmacovigilance services.

Differential diagnosis of contact dermatitis: A practical-approach review by the EADV Task Force on contact dermatitis

The diagnosis of eczema ('dermatitis') is mostly clinical and depends on the clinical history and exploratory objective findings (primary lesions, patterns). Contact dermatitis remains as an important condition in the group of eczematous disorders, with important socioeconomic and occupational relevance. Although irritant and allergic contact dermatitis have a different pathogenesis, both are characterized by a rather typical morphology, are triggered by external factors and tend to occur primarily in the area of contact with the exogenous agent. In addition, allergic and irritant dermatitis may also co-exist. The importance of diagnosing contact dermatitis, especially when allergic in nature, is both due to the possibility of avoiding the trigger, and due to its role in aggravating other skin conditions. Nevertheless, the heterogeneity of clinical presentations in daily practice may pose an important challenge for the suspicion and correct diagnosis of contact dermatitis. Furthermore, other conditions, with different pathogenesis and treatment, may clinically simulate contact dermatitis. The Task Force aims to conduct a review of the unifying clinical features of contact dermatitis and characterize its main clinical phenotypes, and its simulators, in order to contribute to an early suspicion or recognition of contact dermatitis and enable a correct differential diagnosis.

A case of symmetrical drug-related intertriginous and flexural exanthema

Symmetrical drug-related intertriginous and flexural exanthema (also known as Baboon syndrome) is a skin eruption in the intertriginous areas. It is believed to be a delayed-type hypersensitivity response to the drug which occurs secondary to systemic absorption of agents after cutaneous sensitization. Our case provides high quality clinical images to aid in clinical diagnosis of this uncommon skin eruption.

Treating Through Drug-Associated Exanthems in Drug Allergy Management: Current Evidence and Clinical Aspects

In the setting of an acute cutaneous adverse drug reaction there is increasing interest in selected phenotypes and hosts to continue drug therapy, especially in settings in which there are limited therapeutic options. This concept of "treating through," defined as the continued use of a drug in the setting of, in particular maculopapular exanthema, potentially avoids unnecessary drug discontinuation. A review of the recent literature, historical viewpoints, and expert opinion are provided within to form recommendations and algorithms for a "treating-through" approach.

Cross With Caution: Antibiotic Cross-Reactivity and Co-Reactivity Patterns in Severe Cutaneous Adverse Reactions

Current understanding of cross-reactivity in severe cutaneous adverse reactions to beta-lactam antibiotics is limited, thereby making recommendations for future prescribing difficult. The underlying immunopathogenesis of these reactions is not completely understood but involves interactions between small molecule drugs, T cells and HLA molecules. Historically, these reactions were considered to be specific to the inciting antibiotic and therefore likely to have minimal cross-reactivity. We assessed patients presenting with non-SJS/TEN severe cutaneous adverse reactions to a tertiary hospital drug allergy clinic. In our case series cross-reactivity or co-reactivity commonly occurred among the beta-lactam antibiotic class, however further research is required to investigate and understand patterns of cross-reactivity. Based on our experience we provide clinicians with a practical algorithm for testing for cross-reactivity in non-SJS/TEN severe cutaneous adverse reactions.