Current Perspectives on Erythema Multiforme.

Recognition and timely adequate treatment of erythema multiforme remain a major challenge. In this review, current diagnostic guidelines, potential pitfalls, and modern/novel treatment options are summarized with the aim to help clinicians with diagnostic and therapeutic decision-making. The diagnosis of erythema multiforme, that has an acute, self-limiting course, is based on its typical clinical picture of targetoid erythematous lesions with predominant acral localization as well as histological findings.

Current Perspectives on Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis.

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are considered a delayed-type hypersensitivity reaction to drugs. They represent true medical emergencies and an early recognition and appropriate management is decisive for the survival. SJS/TEN manifest with an "influenza-like" prodromal phase (malaise, fever), followed by painful cutaneous and mucous membrane (ocular, oral, and genital) lesions, and other systemic symptoms.

Drug-induced angioedema.

Angioedema (AE) is the end result of deep dermal, subcutaneous and/or submucosal swelling, and represents a major criterion in the definition of anaphylaxis. Drug-induced AE, like other cutaneous drug reactions, is most frequently elicited by betalactam antibiotics and nonsteroidal antiinflammatory drugs. However, differences exist in their underlying pathophysiology (IgE mediated vs.

Cross-reactivity patterns of T cells specific for iodinated contrast media.

Background: Approximately 3% of patients exposed to iodinated contrast media develop delayed hypersensitivity reactions.

Objective: We wanted to better understand the molecular basis of contrast media cross-reactivity.

Methods: Cross-reactivity was assessed by skin testing and measurement of T-cell activation (CD69 upregulation) and proliferation ((3)H-thymidine uptake, 5,6-carboxyfluorescein diacetate succinimidyl ester staining) of PBMCs, T-cell lines, and T-cell clones of 2 patients with delayed hypersensitivity reactions to iohexol and iomeprol, respectively.

Pharmacological interaction of drugs with immune receptors: the p-i concept.

Drug-induced hypersensitivity reactions have been explained by the hapten concept, according to which a small chemical compound is too small to be recognized by the immune system. Only after covalently binding to an endogenous protein the immune system reacts to this so called hapten-carrier complex, as the larger molecule (protein) is modified, and thus immunogenic for B and T cells. Consequently, a B and T cell immune response might develop to the drug with very heterogeneous clinical manifestations.

The immunological and clinical spectrum of delayed drug-induced exanthems.

Purpose Of Review: Drug-induced exanthems are the most common manifestations of drug hypersensitivity and are observed in as much as 2-3% of hospitalized patients. Here we summarize new concepts of the immune mechanisms underlying various forms of drug-induced exanthems.

Recent Findings: Alpha-betaTCR+, CD4 and CD8+ T cells are involved in different drug hypersensitivity reactions.

Systemically induced allergic exanthem from mercury.

Cutaneous reactions to mercury can manifest themselves in different forms. Apart from contact dermatitis, flare-up reactions, disseminated exanthem as well as skin symptoms in previously unaffected skin are known. Regarding systemic allergen application, 2 separate clinical patterns, namely acute generalized exanthematous pustulosis (AGEP) and symmetric flexural exanthem 'baboon syndrome' have been described.