Patch testing is the only clinically applicable diagnostic method for Type IV allergy. The availability of Type IV patch test (PT) allergens in Europe, however, is currently scarce. This severely compromises adequate diagnostics of contact allergy, leading to serious consequences for the affected patients. Against this background, the European Society of Contact Dermatitis (ESCD) has created a task force (TF) (i) to explore the current availability of PT substances in different member states, (ii) to highlight some of the unique characteristics of Type IV vs. other allergens and (iii) to suggest ways forward to promote and ensure availability of high-quality patch testing substances for the diagnosis of Type IV allergies throughout Europe. The suggestions of the TF on how to improve the availability of PT allergens are supported by the ESCD, the European Academy of Allergy and Clinical Immunology, and the European Academy of Dermatology and Venereology and intend to provide potential means to resolve the present medical crisis.
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.
The role of T cell receptor (TCR) diversity in infectious disease susceptibility is not well understood. We use a systems immunology approach on three cohorts of herpes zoster (HZ) patients and controls to investigate whether TCR diversity against varicella-zoster virus (VZV) influences the risk of HZ. We show that CD4+ T cell TCR diversity against VZV glycoprotein E (gE) and immediate early 63 protein (IE63) after 1-week culture is more restricted in HZ patients. Single-cell RNA and TCR sequencing of VZV-specific T cells shows that T cell activation pathways are significantly decreased after stimulation with VZV peptides in convalescent HZ patients. TCR clustering indicates that TCRs from HZ patients co-cluster more often together than TCRs from controls. Collectively, our results suggest that not only lower VZV-specific TCR diversity but also reduced functional TCR affinity for VZV-specific proteins in HZ patients leads to lower T cell activation and consequently affects the susceptibility for viral reactivation.
Herpes Zoster , Herpesvirus 3, Human , Lymphocyte Activation , Receptors, Antigen, T-Cell , Humans , Herpes Zoster/immunology , Herpes Zoster/virology , Receptors, Antigen, T-Cell/metabolism , Receptors, Antigen, T-Cell/immunology , Lymphocyte Activation/immunology , Herpesvirus 3, Human/immunology , Female , Middle Aged , Male , CD4-Positive T-Lymphocytes/immunology , Aged , Adult , Epitopes, T-Lymphocyte/immunology
Dermatitis, Allergic Contact , Dermatitis, Occupational , Dust , Wood , Humans , Wood/adverse effects , Dermatitis, Occupational/etiology , Dermatitis, Occupational/diagnosis , Dermatitis, Allergic Contact/etiology , Dermatitis, Allergic Contact/diagnosis , Conjunctivitis, Allergic/chemically induced , Conjunctivitis, Allergic/etiology , Male , Asthma/etiology , Adult , Beauty Culture , Female , Patch Tests , Middle Aged
The varicella-zoster virus (VZV) infects over 95% of the population. VZV reactivation causes herpes zoster (HZ), known as shingles, primarily affecting the elderly and immunocompromised individuals. However, HZ can also occur in otherwise healthy individuals. We analyzed the immune signature and risk profile in HZ patients using a genome-wide association study across different UK Biobank HZ cohorts. Additionally, we conducted one of the largest HZ HLA association studies to date, coupled with transcriptomic analysis of pathways underlying HZ susceptibility. Our findings highlight the significance of the MHC locus for HZ development, identifying five protective and four risk HLA alleles. This demonstrates that HZ susceptibility is largely governed by variations in the MHC. Furthermore, functional analyses revealed the upregulation of type I interferon and adaptive immune responses. These findings provide fresh molecular insights into the pathophysiology and the activation of innate and adaptive immune responses triggered by symptomatic VZV reactivation.
Dermatitis, Allergic Contact , Eczema, Dyshidrotic , Eczema , Hand Dermatoses , Intrauterine Devices , Humans , Female , Dermatitis, Allergic Contact/diagnosis , Dermatitis, Allergic Contact/etiology , Copper/adverse effects , Hand Dermatoses/chemically induced , Hand Dermatoses/diagnosis , Patch Tests
BACKGROUND: A popular antiseptic spray in Switzerland (Merfen spray), containing chlorhexidine digluconate, benzoxonium chloride and lauramine oxide, is frequently used to treat skin wounds. However, it is also increasingly reported as a major cause of adverse skin reactions, including allergic contact dermatitis (ACD). OBJECTIVES: To investigate the contact allergens responsible for ACD from this antiseptic. PATIENTS/METHODS: Patch tests were performed on seven patients with a clinical history compatible with contact dermatitis from this antiseptic mixture. RESULTS: All patients presented with acute eczematous reactions following contact with either Merfen spray alone, or with multiple products including this spray. Patients showed positive reactions to this product in both patch tests and repeated open application tests (ROATs). Four patients showed dose-dependent reactions to both benzoxonium chloride and lauramine oxide. One patient showed a dose-dependent reaction to the former and a non-dose-dependent reaction to the latter. Finally, two subjects showed responses only to lauramine oxide. One patient reacted to chlorhexidine digluconate 0.5% aq. in addition to both other allergens. CONCLUSIONS: Two commercially unavailable allergens, that is, benzoxonium chloride and/or lauramine oxide were identified as major causes of ACD from Merfen antiseptic spray, whereas chlorhexidine digluconate was a contributing culprit in only one patient.
Anti-Infective Agents, Local , Dermatitis, Allergic Contact , Humans , Anti-Infective Agents, Local/adverse effects , Chlorhexidine/adverse effects , Allergens/adverse effects , Dermatitis, Allergic Contact/diagnosis , Dermatitis, Allergic Contact/etiology , Switzerland , Patch Tests/adverse effects , Oxides
Acrylonitrile , Dermatitis, Allergic Contact , Dermatitis, Occupational , Humans , Dermatitis, Allergic Contact/diagnosis , Dermatitis, Allergic Contact/etiology , Acrylonitrile/adverse effects , Dermatitis, Occupational/diagnosis , Dermatitis, Occupational/etiology , Allergens , Industry , Patch Tests
The European baseline series was last updated in 2019. This article discusses the reasoning behind a further iteration of the series for 2023.
Dermatitis, Allergic Contact , Humans , Dermatitis, Allergic Contact/diagnosis , Dermatitis, Allergic Contact/etiology , Allergens , Patch Tests , Europe
