S3 Guideline Urticaria. Part 1: Classification and diagnosis of urticaria - German-language adaptation of the international S3 Guideline.

The lifetime prevalence of urticaria, a severe allergic disease, is almost 20%. It not only limits the quality of life of those affected, but also their general performance at work and in their daily activities. This publication is the first section of the Urticaria Guideline. It covers the classification and diagnosis of urticaria, taking into account the major advances in research into its causes, triggering factors and pathomechanisms. It also addresses strategies for the efficient diagnosis of the different subtypes of urticaria. This is crucial for individual, patient-oriented treatment, which is covered in the second part of the guideline, published separately. This German-language guideline was developed according to the criteria of the AWMF on the basis of the international English-language S3 guideline with special consideration of health system characteristics in the German-speaking countries. This first part of the guideline describes the classification of urticaria, distinguishing spontaneously occurring wheals (hives) and angioedema from forms of urticaria with inducible symptoms. Urticaria is defined as sudden onset of wheals, angioedema, or both, but is to be distinguished from conditions in which wheals occur as a short-term symptom, such as anaphylaxis. The diagnosis is based on (a limited number of) laboratory tests, but especially on medical history. In addition, validated instruments are available to measure the severity, activity and course of the disease.

S3 Guideline Urticaria. Part 2: Treatment of urticaria - German-language adaptation of the international S3 guideline.

This publication is the second part of the German-language S3 guideline on urticaria. It covers the management of urticaria and should be used together with Part 1 of the guideline on classification and diagnosis. This publication was prepared according to the criteria of the AWMF on the basis of the international English-language S3 guideline with special consideration of health system conditions in German-speaking countries. Chronic urticaria has a high impact on the quality of life and daily activities of patients. Therefore, if causal factors cannot be eliminated, effective symptomatic treatment is necessary. The recommended first-line treatment is to administer new generation, non-sedating H1 antihistamines. If the standard dose is not sufficiently effective, the dose should be increased up to fourfold. For patients who do not respond to this treatment, the second-line treatment in addition to antihistamines in the treatment algorithm is omalizumab and, if this treatment fails, ciclosporin. Other low-evidence therapeutic agents should only be used if all treatments in the treatment algorithm agreed upon by the guideline group fail. Both the benefit-risk profile and cost should be considered. Corticosteroids are not recommended for long-term treatment due to their inevitable severe side effects.

S2k guideline diagnosis, prevention, and therapy of hand eczema.

The consensus-based guideline "Diagnosis, prevention, and treatment of hand eczema (HE)" provides concrete instructions and recommendations for diagnosis, prevention, and therapy of HE based on an evidence- and consensus-based approach. The guideline was created based on the German guideline "Management von Handekzemen" from 2009 and the current guideline of the European Society of Contact Dermatitis (ESCD) "Guidelines for diagnosis, prevention, and treatment of hand eczema" from 2022. The general goal of the guideline is to provide dermatologists and allergologists in practice and clinics with an accepted, evidence-based decision-making tool for selecting and conducting suitable and sufficient therapy for patients with hand eczema. The guideline is based on two Cochrane reviews of therapeutic and preventive interventions for HE. The remaining chapters were mainly developed and consented based on non-systematic literature research by the expert group. The expert group consisted of members of allergological and occupational dermatological professional associations and working groups, a patient representative, and methodologists. The proposals for recommendations and key statements were consented by using a nominal group process during a consensus conference on September 15, 2022. The structured consensus-building process was professionally moderated. This guideline is valid until February 22, 2028.

German S1 guideline: Contact dermatitis.

Contact dermatitis is an inflammation of the epidermis and dermis at the site of exposure triggered by external agents. The two main forms are irritant and allergic contact dermatitis, which cause significant health and socioeconomic costs in addition to a marked reduction in quality of life. The anamnesis and the clinical picture are decisive for the necessary diagnostic measures. The most accurate possible diagnostic classification of contact dermatitis by means of allergological testing is important for disease management, since not only classical eczema therapy but also avoidance of the exogenous triggering factors are of great importance here. The choice of therapy should be based on the acuity, clinical severity, morphology of the lesions and localization of the contact dermatitis. A combination of basic therapy, topical, physical, and systemic therapy adapted to the patient's needs is required, whereby not all forms of therapy must be carried out simultaneously but can be used in a varying manner. Primary, secondary, and tertiary prevention strategies aim at the recognition of the triggering noxae or allergens with subsequent contact avoidance or minimization. The present S1-guideline on contact dermatitis is primarily intended to provide dermatologists, allergologists and physicians working in allergology and occupational dermatology with a decision-making aid for the selection and implementation of suitable and sufficient diagnostics, therapy, and prevention.

Inter-α-Trypsin Inhibitor Heavy Chain 5 (ITIH5) Is a Natural Stabilizer of Hyaluronan That Modulates Biological Processes in the Skin.

INTRODUCTION: Hyaluronan (HA) is a major component of the skin that exerts a variety of biological functions. Inter-α-trypsin inhibitor heavy chain (ITIH) proteins comprise a family of hyaladherins of which ITIH5 has recently been described in skin, where it plays a functional role in skin morphology and inflammatory skin diseases including allergic contact dermatitis (ACD). OBJECTIVE: The current study focused on the ITIH5-HA interaction and its potential clinical and functional impact in extracellular matrix (ECM) stabilization. METHODS: Studying the molecular effects of ITIH5 in skin, we established skin models comprising murine skin cells of Itih5 knockout mice and corresponding wild-type controls. In addition, human dermal fibroblasts with an ITIH5 knockdown as well as a murine recombinant Itih5 protein were established to examine the interaction between ITIH5 and HA using in vitro adhesion and HA degradation assays. To understand more precisely the role of ITIH5 in inflammatory skin diseases such as ACD, we generated ITIH5 knockout cells of the KeratinoSens® cell line. RESULTS: Using murine skin models, ITIH5 knockdown fibroblasts, and a reactive oxygen species (ROS)-mediated HA degradation assay, we proved that ITIH5 binds to HA, thereby acting as a stabilizer of HA. Moreover, microarray profiling revealed the impact of ITIH5 on biological processes such as skin development and ECM homeostasis. Performing the in vitro KeratinoSens skin sensitization assay, we detected that ITIH5 decreases the sensitizing potential of moderate and strong contact sensitizers. CONCLUSION: Taken together, our experiments revealed that ITIH5 forms complexes with HA, thereby on the one hand stabilizing HA and facilitating the formation of ECM structures and on the other hand modulating inflammatory responses.

A EAACI drug allergy interest group survey on how European allergy specialists deal with ß-lactam allergy.

An accurate diagnosis of ß-lactam (BL) allergy can reduce patient morbidity and mortality. Our aim was to investigate the availability of BL reagents, their use and test procedures in different parts of Europe, as well as any differences in the diagnostic workups for evaluating subjects with BL hypersensitivity. A survey was emailed to all members of the EAACI Drug Allergy Interest Group (DAIG) between February and April 2016, and the questionnaire was meant to study the management of suspected BL hypersensitivity. The questionnaire was emailed to 82 DAIG centres and answered by 57. Amoxicillin alone or combined to clavulanic acid were the most commonly involved BL except in the Danish centre, where penicillin V was the most frequently suspected BL. All centres performed an allergy workup in subjects with histories of hypersensitivity to BL: 53 centres (93%) followed DAIG guidelines, two national guidelines and two local guidelines. However, there were deviations from DAIG recommendations concerning allergy tests, especially drug provocation tests. A significant heterogeneity exists in current practice not only among countries, but also among centres within the same country. This suggests the need to re-evaluate, update and standardize protocols on the management of patients with suspected BL allergy.

[The aryl hydrocarbon receptor as the target structure for new drugs in psoriasis and atopic dermatitis]. / Aryl-Hydrocarbon-Rezeptor als Zielstruktur für neue Medikamente bei Psoriasis und atopischer Dermatitis.

Coal tar therapy was used for centuries to treat skin disorders characterised by inflammation and skin barrier damage. It has been shown that the aryl hydrocarbon receptor (AhR) is the key target structure for these pharmacological effects of coal tar. Since coal tar has been used less and less because of the carcinogenicity of many ingredients of coal tar, other ligands of AhR were studied. Tapinarof is such a ligand and proved to be a promising new drug to treat psoriasis and atopic dermatitis. Since many endogenous and exogenous ligands of AhR are known, it may be that this "tar-smart" product is a first example of a new drug family with which dermatologists can treat skin disorders that are characterized by inflammation and skin barrier damage.

S3 guidelines: Epicutaneous patch testing with contact allergens and drugs - Short version, Part 1.

Epicutaneous patch testing is the diagnostic standard for the detection of allergic contact dermatitis. The present guidelines are aimed at residents and board-certified physicians in the fields of dermatology and allergology as well as other medical specialties involved in establishing the indication for patch testing and its execution in patients with contact dermatitis and other forms of delayed-type hypersensitivity. The target audience also includes other health care providers and insurance funds. Based on a systematic literature search and a formal consensus process (S3), the guidelines were developed by dermatologists in collaboration with pediatricians, occupational medicine physicians, nursing staff as well as patient representatives. The systematic methodological approach and appraisal of evidence upon which the recommendations are based are outlined in a separate method report that also contains evidence tables. The guidelines address general aspects of patch testing as well as medicolegal issues. The recommendations given relate to topics such as the indication for patch testing, informed patient consent, as well as the choice of test substances, test chambers and test site, duration of exposure, reading times and interpretation of test reactions. Furthermore, recommendations are provided with respect to endogenous and exogenous factors, specific patient groups (children, pregnant women, immunosuppressed individuals) as well as possible risks and adverse events associated with patch testing using contact allergens. Note: This publication is part 1 of the short version of the S3 guidelines for "Epicutaneous patch testing using contact allergens and drugs" (registry no. 013 - 018; date: March 20, 2019; valid until December 31, 2021). Part 2 of the short version will be published in the next issue. The long version of these guidelines can be accessed at www.awmf.org. The method report is available as online publication (https://www.awmf.org/leitlinien/detail/ll/013-018.html) and contains the evidence tables in its appendix.

S3 Guidelines: Epicutaneous patch testing with contact allergens and drugs - Short version, Part 2.

Epicutaneous patch testing is the diagnostic standard for the detection of allergic contact dermatitis. The present guidelines are aimed at residents and board-certified physicians in the fields of dermatology and allergology as well as other medical specialties involved in establishing the indication for patch testing and its execution in patients with contact dermatitis and other forms of delayed-type hypersensitivity. The target audience also includes other health care providers and insurance funds. Based on a systematic literature search and a formal consensus process (S3), the guidelines were developed by dermatologists in collaboration with pediatricians, occupational medicine physicians, nursing staff as well as patient representatives. The systematic methodological approach and appraisal of evidence upon which the recommendations are based are outlined in a separate method report that also contains evidence tables. The guidelines address general aspects of patch testing as well as medicolegal issues. The recommendations given relate to topics such as the indication for patch testing, informed patient consent, as well as the choice of test substances, test chambers and test site, duration of exposure, reading times and interpretation of test reactions. Furthermore, recommendations are provided with respect to endogenous and exogenous factors, specific patient groups (children, pregnant women, immunosuppressed individuals) as well as possible risks and adverse events associated with patch testing using contact allergens.

Hyperpigmentation and higher incidence of cutaneous malignancies in moderate-high PCB- and dioxin exposed individuals.

Polychlorinated biphenyls (PCB) are well known persistent and toxic environmental pollutants. Our aim was to identify effects of moderate-high exposure to dioxin-like (dl) and non-dioxin-like (ndl)-PCBs on the skin in order to provide more insight in the pathophysiological effects of these compounds. We performed a dermatological examination on 92 former workers from a transformer recycling company with known elevated serum PCB and/or dioxin (polychlorinated dibenzo-p-dioxin/polychlorinated dibenzo-p-furan (PCDD/F)) levels. In addition, we performed a skin cancer screening over a period of seven years (2010-2016) on resp. 268, 271, 210, 149, 92, 129 and 79 participants. We found a higher incidence of acne and malignancies of the skin (malignant melanoma, basal cell carcinoma and mycosis fungoides) in the workers compared to normal population. The probability of having hyperpigmentation on the skin was statistically significantly higher in workers with higher sumPCBs- (OR:1.09(1.12-2.17)), dioxin-like (dl)-PCBs- (OR:1.56(1.12-2.17)) and dioxin (PCDD/Fs) (OR:1.09(1.02-1.16)) levels. Age was a confounding factor in this model. Formation of hyperpigmentation could be an indicator for (moderate-high) exposure to toxic compounds like PCBs. The higher incidence of cutaneous malignancies found in the workers might be associated with PCB- and dioxin exposure, warranting further investigation on larger cohorts.

Occupational generalized urticaria and anaphylaxis after inhalation of cefuroxime in a nurse.

We present the case of a 53 years old nonatopic female nurse who experienced repeated anaphylactic reactions at work without involvement in drug-specific tasks such as crushing of tablets or preparation of injections. The causal allergen was not identified until a further severe anaphylactic reaction occurred after oral use of cefuroxime during a respiratory infection. Sensitization to cefuroxime was demonstrated by specific IgE, basophil activation test and skin prick test. An inhalation challenge with a dosimeter induced generalized urticaria after a cumulative dose of about 10 µg of the drug, but no asthmatic reaction. Complete exposure cessation was initiated and a 1-year follow-up was without further allergic reactions. We conclude that work-related systemic allergic reactions to ß-lactam antibiotics may occur in nurses after inhalation of low doses and without perceived association with drug-specific tasks like handling of antibiotics.

Commentary on the "Evidence- and Consensus-Based (S3) Guidelines for the Treatment of Actinic Keratosis" Published by the International League of Dermatological Societies in Cooperation with the European Dermatology Forum.

In 2015, the International League of Dermatological Societies and the European Dermatology Forum published a guideline for the treatment of actinic keratosis, which is classified as an evidence- and consensus-based S3 guideline. From the point of view of the GD Task Force "Licht.Hautkrebs.Prävention," an interdisciplinary expert panel of the Society for Dermopharmacy for the prevention and treatment of skin cancer, this guideline reveals strengths and weaknesses but, in summary, does not meet the claim for an evidence- and consensus-based S3 guideline.

Individual risk assessment in the diagnosis of immediate type drug hypersensitivity reactions to betalactam and non-betalactam antibiotics using basophil activation test: a single center experience.

BACKGROUND: Drug hypersensitivity reactions of immediate type pose a challenging problem, especially, if standard diagnostic procedures do not lead to conclusive results. The aim of this investigation is to identify, whether basophil activation test (BAT) is able to provide additional benefit in the diagnostic evaluation of immediate type drug hypersensitivity reactions to antibiotics in comparison with the routine allergological diagnostic methods. MATERIALS AND METHODS: We investigated patients, who presented to the Department of Dermatology and Allergology of the University Hospital of RWTH Aachen in Germany for diagnostic workup of type I allergic reactions to antibiotics during the period from 2009 to 2012. The analysis was performed retrospectively based on patient records. The inclusion criteria were performed standard allergological in vivo diagnostic and a BAT as a part of diagnostic workup. RESULTS: Eighty-two diagnostic investigations were performed in 52 patients. BAT was positive in 9 of 12 cases with a positive clinical history but negative skin test results. Furthermore, all patients who reported severe drug hypersensitivity reactions (anaphylactic reaction grade 2 and above) showed positive BAT (5/5), while only three of these five cases demonstrated a positive skin testing that led to the conclusion of possible immediate type drug hypersensitivity. CONCLUSIONS: Although skin tests remain the most important part of the primary diagnostic investigation, BAT is an additional valuable and sensitive in vitro test in the diagnostic procedure of immediate type allergic reactions to antibiotics. However, further standardized investigations are needed in order to calculate exact sensitivity and specificity of this diagnostic tool in both, adult and pediatric populations.

Cutaneous allergic drug reactions: update on pathophysiology, diagnostic procedures and differential diagnosic.

Important changes in the understanding and management of drug hypersensitivity reactions during the last years result from the increasing importance of biologics in medical practice, which differ in their spectrum of adverse drug reactions (ADRs) from the classical covalent drugs. With regard to covalent drugs, ampicillin and amoxicillin as well as clavulanic acid play an increasing role among ADRs to betalactam antibiotics. Fluoroquinolones are mainly the cause of anaphylactic and photosensitivity reactions. Especially in allergic reactions to NSAIDs, pseudoallergic reactions should be considered in the differential diagnosis. In opposite to the main cutaneous allergic drug reactions such as urticaria or maculopapular skin rash, in which antibiotics are the main culprits, in severe drug allergic reactions such as SJS (Stevens-Johnson Syndrome), TEN (Toxic Epidermal Necrolysis), or DRESS (Drug Reaction with Eosinophilia and Systemic Symptoms) Syndrome, compounds like allopurinol and anticonvulsants are the main causes. Similar mutations in the IL36R gene, which were found in both patients with an AGEP (Acute Generalized Exanthematous Pustulosis) and pustular psoriasis, make the differential diagnosis more difficult and raise the question whether there is a difference between these diseases or whether AGEP is not just a drug induced pustular psoriasis. Finally, some special aspects of side effects of biologics and targeted therapies respectively are discussed.

Prospective, Randomized Study on the Efficacy and Safety of Local UV-Free Blue Light Treatment of Eczema.

BACKGROUND: Blue light was shown to reduce the activation of T cells and modulate cytokine release in vitro. Therefore, we investigated the efficacy of blue light in the treatment of eczema. METHODS: A sample of 21 patients with mild to moderate eczema were locally treated with blue LED light (light-emitting diode, emission maximum: 453 nm). They received light treatment 3 times per week for 4 weeks. A contralateral control lesion remained untreated. RESULTS: A total of 20 patients completed the trial with a compliance rate of 100%. The blue light treatment was safe with no adverse events and no side effects. The primary end point change from baseline in the mean sum score of the local Eczema Severity Index (local ESI) was more pronounced for the treated area than for the control area (-1.9 ± 2.02 vs. -1.3 ± 2.24). The treatment difference was statistically significant (p = 0.0152, paired t test, two-sided). CONCLUSION: In this study UV-free blue light was safe and effective in the reduction of eczema lesions.