What's already known about this topic?

• The prevalence of psoriasis in children is lower than in adults, but the significant number of adults who first developed skin disease in childhood supports the frequent persistence of psoriasis into adulthood.
• Genetic and environmental factors both play an important role in the onset of psoriasis.
• Disease associations, such as obesity, are an important area of current research activity.

What does this study add?

• Mapping has shown a dramatic increase in the number of published studies over the past 25 years.
• Studies have been concentrated in Europe, Asia and North America. These studies have largely been case series or cross-sectional studies.
• Specific studies with standardized methodologies are needed to provide data on the frequency, clinical presentation, risk factors, associated diseases and long-term outcomes for childhood-onset psoriasis.

Linked Comment: Dowlatshahi and Wakkee. Br J Dermatol 2016; 174: 1180–1181.

What's already known about this topic?

• Basal cell carcinoma (BCC) is the most common (skin) cancer in Europe. Its incidence is rising dramatically, and it is associated with an important direct treatment cost for healthcare budgets.
• BCCs slowly increase in size, with a median increase in diameter of 0·5 mm over 10 weeks.
• Delays in diagnosis and appropriate treatment are the most important underlying causes of giant BCC and metastasis.

What does this study add?

• Early detection and starting of adequate treatment of BCC seem to be crucial for BCC of the face, more specifically in the H-zone.
• Small changes in size can affect treatment options (e.g. type of surgery), their effectiveness and the associated costs.

Linked Comment: Linos and Chren. Br J Dermatol 2016; 174: 1181–1182.

Linked Comment: Wisco and Adelson. Br J Dermatol 2016; 174: 1182–1183.

Plain language summary available online

What's already known about this topic?

• Psoriasis is a common, chronic, immune-mediated inflammatory skin disease.
• Key cytokines involved in the pathogenesis of psoriasis use the Janus kinase–signal transducer and activator of transcription (JAK-STAT) pathway.
• New safe and effective therapies are needed for patients.

What does this study add?

• Baricitinib, a selective JAK1/JAK2 inhibitor, demonstrates clinical efficacy in the treatment of psoriasis.
• Baricitinib was well tolerated over the 24-week trial period.

Linked Comment: Albrecht and Gerdes. Br J Dermatol 2016; 174: 1183–1184.

What's already known about this topic?

• Alitretinoin is a retinoid X receptor and retinoid A receptor agonist with effects on cutaneous inflammation and hyperkeratinization.
• Findings from earlier uncontrolled studies of alitretinoin indicate that it could be a meaningful treatment option for palmoplantar pustulosis.

What does this study add?

• Although the results were unexpected based on previous studies of alitretinoin in the treatment of palmoplantar pustulosis, this study provided no evidence to support further exploration of alitretinoin in the treatment of severe palmoplantar pustulosis.

What's already known about this topic?

• Pemphigus is associated with morbidity and mortality.
• The inpatient comorbidities and mortality of pemphigus have not been well described.

What does this study add?

• The present study revealed novel associations between pemphigus and numerous medical and mental health comorbidities in children and adults, including infections and autoimmune, cardiovascular, endocrine, haematological and neuropsychiatric disorders.
• Although inpatient mortality rates for patients with pemphigus were higher than for those without pemphigus, we found substantially lower inpatient mortality rates than traditionally reported in pemphigus.

Linked Comment: Murrell. Br J Dermatol 2016; 174: 1185–1186.

Plain language summary available online

What's already known about this topic?

• A high-glycaemic-load diet and insulin-like growth factor-1 play roles in the induction of acne.
• Increased mammalian target of rapamycin (mTOR)C1 signalling has been reported in patients with acne compared with healthy controls.

What does this study add?

• This study provides immunohistochemical evidence of increased cytoplasmic expression of the metabolic transcription factor FoxO1 and increased expression of mTOR in the skin of patients with acne.
• We provide experimental evidence supporting the hypothesis of decreased nuclear FoxO1 signalling in patients with acne.

What is the translational message?

• Nutritional therapy for acne should (i) normalize total calorie intake, (ii) lower glycaemic load and (iii) restrict total dairy protein consumption.
• Understanding nutrient signalling may help dermatologists to understand the central role of the Western diet in the pathogenesis and treatment of acne.
• Our results may offer novel therapeutic strategies for the treatment of acne based on upregulation of nuclear FoxO1.

Linked Comment: Melnik. Br J Dermatol 2016; 174: 1186–1188.

Plain language summary available online

What's already known about this topic?

• Melanoma risk is determined by environmental and genetic risk factors.
• The frequency and type of disease-causing gene mutations vary between different countries.

What does this study add?

• This is the first comprehensive description of Austrian patients at high risk of melanoma.
• The heterogeneity of the different subgroups suggests diverse pathways.
• We present functional prediction of MC1R and CDK4 variants with unknown biological significance in high-risk patients, and three novel cases with MITF variants in high-risk patients.

What is the translational message?

• Identification of high-risk individuals helps to reduce mortality.
• The risk of melanoma is comprised of a complex interplay between genetic and environmental factors; however, genetic mutations associated with melanoma might differ from country to country.
• Knowledge of these mutations and adjustment of criteria for testing could be required for adequate risk assessments.

Linked Comment: Stefanaki and Stratigos. Br J Dermatol 2016; 174: 1188–1190.

Plain language summary available online

What's already known about this topic?

• A T-cell-mediated immune response is responsible for melanocyte destruction in vitiligo.
• CXCL10 is critical for the progression and maintenance of depigmentation in a mouse model of vitiligo.

What does this study add?

• CXCL9 and CXCL10, in parallel with their receptor, CXCR3, are present in patients with vitiligo and correlate with disease activity and severity.
• Serum CXCL10 may be a novel biomarker in monitoring disease activity and guiding treatment of progressive vitiligo.

What is the translational message?

• Blocking the CXCL10/CXCR3 chemotactic mechanism may present a new form of therapy for progressive vitiligo.

Linked Comment: Rashighi and Harris. Br J Dermatol 2016; 174: 1190–1191.

Plain language summary available online

What's already known about this topic?

• YKL-40, secreted by activated macrophages and neutrophils, is a potential biomarker of inflammation and endothelial dysfunction.
• Behçet disease (BD) is a chronic multisystemic inflammatory disease, characterized by neutrophil hyperactivation and endothelial injury with subsequent dysfunction.

What does this study add?

• Serum YKL-40 levels are increased in patients with BD and positively correlate with disease activity.
• YKL-40 may play a role in the pathophysiology of BD and could provide a useful marker for monitoring patients with BD.

What's already known about this topic?

• Itch is frequently associated with primary localized cutaneous amyloidosis (PLCA) and can be debilitating; its pathophysiology is unknown.

What does this study add?

• Small-fibre neuropathy is present in PLCA.
• Pruritus in PLCA is likely associated with hypersensitivity of cutaneous nerve fibres, which may be related to an increased expression of epidermal interleukin (IL)-31 receptors.
• Targeting IL-31 receptors is a potential therapeutic approach.

Linked Comment: Schreml. Br J Dermatol 2016; 174: 1192–1193.

What's already known about this topic?

• A unifying language and precise descriptions are key to the practice of dermatology.
• The International League of Dermatological Societies (ILDS) first published a ‘Glossary of basic dermatology lesions’ in 1987.

What does this study add?

• This is an entirely updated and revised version of the 1987 ILDS glossary.
• The revised nomenclature is written with both dermatologists and nondermatologists in mind.

What's already known about this topic?

• Nonsurgical treatment including laser ablation of skin cancer is limited by lack of histologically confirmed clearance.
• Reflectance confocal microscopy provides noninvasive, in vivo imaging of skin with cellular-level resolution

What does this study add?

• Confocal microscopy can effectively map tumour margins preablation and also detect residual tumour postablation.
• Carbon dioxide laser ablation guided by confocal microscopy may represent a suitable alternative treatment for low-risk basal cell carcinoma in nonsurgical candidates.