This update and revision of the international guideline for urticaria was developed following the methods recommended by Cochrane and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) working group. It is a joint initiative of the Dermatology Section of the European Academy of Allergology and Clinical Immunology (EAACI), the Global Allergy and Asthma European Network (GA²LEN) and its Urticaria and Angioedema Centers of Reference and Excellence (UCAREs and ACAREs), the European Dermatology Forum (EDF; EuroGuiDerm), and the Asia Pacific Association of Allergy, Asthma and Clinical Immunology with the participation of 64 delegates of 50 national and international societies and from 31 countries. The consensus conference was held on 3 December 2020. This guideline was acknowledged and accepted by the European Union of Medical Specialists (UEMS). Urticaria is a frequent, mast cell–driven disease that presents with wheals, angioedema, or both. The lifetime prevalence for acute urticaria is approximately 20%. Chronic spontaneous or inducible urticaria is disabling, impairs quality of life, and affects performance at work and school. This updated version of the international guideline for urticaria covers the definition and classification of urticaria and outlines expert‐guided and evidence‐based diagnostic and therapeutic approaches for the different subtypes of urticaria.

Psoriasis is a common disease, which has a considerable impact on the healthcare system. Therefore, appropriate use of therapeutic resources is very important. Management of psoriasis in daily clinical practice is highly variable because many issues are still debated and not definitely addressed by the evidence‐based medicine. Moreover, the different availability and reimbursability of drugs in each country justifies national guidelines. Expert consensus can provide helpful guidelines for optimizing patient care. A total of 20 dermatologists from different areas of Italy and with large experience in the treatment of psoriasis agreed to participate in the guidelines expert panel who aimed to reach consensus on the factors influencing psoriasis severity, the indications for systemic treatments, the parameters to be considered in the choice of treatment, and the factors to be considered in the choice of biological treatment. The recommendations for the use, screening and monitoring of systemic therapies were based on the 2015 S3 European Dermatology Forum/European Academy of Dermatology and Venereology psoriasis guidelines. Recommendations on the treatment of psoriasis in special patient populations were also agreed. The final document was discussed in a meeting moderated by a facilitator with participation of the entire group and adopting a nominal group technique to reach consensus. A statement was regarded as consented when agreement was achieved by at least 75% of the voting experts according to the Delphi procedure.

Inflammatory bowel diseases (IBDs) may be associated with extra-intestinal manifestations. Among these, mucocutaneous manifestations are relatively frequent, often difficult to diagnose and treat, and may complicate the course of the underlying disease. In the present review, a summary of the most relevant literature on the dermatologic manifestations occurring in patients with inflammatory bowel diseases has been reviewed. The following dermatological manifestations associated with IBDs have been identified: (i) specific manifestations with the same histological features of the underlying IBD (occurring only in Crohn’s disease); (ii) cutaneous disorders associated with IBDs (such as aphthous stomatitis, erythema nodosum, psoriasis, epidermolysis bullosa acquisita); (iii) reactive mucocutaneous manifestations of IBDs (such as pyoderma gangrenosum, Sweet’s syndrome, bowel-associated dermatosis-arthritis syndrome, aseptic abscess ulcers, pyodermatitis–pyostomatitis vegetans, etc.); (iv) mucocutaneous conditions secondary to treatment (including injection site reactions, infusion reactions, paradoxical reactions, eczematous and psoriasis-like reactions, cutaneous infections, and cutaneous malignancies); (v) manifestations due to nutritional malabsorption (such as stomatitis, glossitis, angular cheilitis, pellagra, scurvy, purpura, acrodermatitis enteropathica, phrynoderma, seborrheic-type dermatitis, hair and nail abnormalities). An accurate dermatological examination is essential in all IBD patients, especially in candidates to biologic therapies, in whom drug-induced cutaneous reactions may assume marked clinical relevance.

Patch testing is the standard procedure used to diagnose allergic contact dermatitis. It is an in-vivo test, which reproduces the reaction to a contact allergen. This in-vivo test aims to reproduce the elicitation phase of allergic contact dermatitis and is performed applying allergens under occlusion on the skin under standardized conditions. These guidelines for the best practice in performing patch test have been developed by an Italian group of experts taking in account the Italian legislation and local pharmacological governance. Guidelines are adapted from the original article under the guidance of the European Society of Contact Dermatitis (ESCD) and on the basis of the SIDAPA guidelines.