The international EAACI/GA²LEN/EuroGuiDerm/APAAACI guideline for the definition, classification, diagnosis, and management of urticaria.

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.

Papillomatosis cutis lymphostatica and 'Ski-Jump' nails.

Papillomatosis cutis lymphostatica is an uncommon condition usually associated with lymphedema. "Ski-jump" nails are upward sloping concave nails that can be an important diagnostic sign which may be overlooked in the setting of lymphedema. A diagnosis of papillomatosis cutis lymphostatica should be suspected in patients presenting with persistent, bland papilliform plaques, supported by the additional presence of "ski-jump" nails.

Cutaneous Melanoma More Likely to Be Invasive in Fairer Skin Phototypes: A Retrospective Observational Study.

Fitzpatrick skin phototype is one of the factors determining melanoma development, with fairer skin phototypes I and II known to be associated with a higher risk. This study aimed to identify any associations between skin phototype and the histologic subtype, Breslow's thickness, and the site of melanoma. Patients diagnosed with melanoma for over an 18-month period were included. Data were gathered from the Malta National Cancer Registry. There were 167 registered cutaneous melanoma patients, of which 135 were included in the study. Melanomas in patients with skin phototypes I and II were more likely to be invasive than in situ when compared to patients with skin phototypes III and IV (P = 0.00027). There was also an association between skin phototype and histologic type of melanoma (P = 0.005), with melanoma in situ being the most common subtype in patients with skin type III. This study confirms that fairer skin phototypes have an increased risk of melanoma. It also shows that in our population, melanoma in skin phototypes I and II is more likely to be invasive rather than in situ compared to melanoma in darker skin phototypes. Further studies are required to confirm these findings and identify possible reasons.

A novel SPINK5 donor splice site variant in a child with Netherton syndrome.

BACKGROUND: Netherton syndrome (NS) is a genodermatosis caused by loss-of-function mutations in SPINK5, resulting in aberrant LEKTI expression. METHOD: Next-generation sequencing of SPINK5 (NM_001127698.1) was carried out and functional studies were performed by immunofluorescence microscopy of a lesional skin biopsy using anti-LEKTI antibodies. RESULTS: We describe a novel SPINK5 likely pathogenic donor splice site variant (NM_001127698.1:c.2015+5G>A) in a patient with NS and confirm its functional significance by demonstrating complete loss of LEKTI expression in lesional skin by immunofluorescence analysis. CONCLUSION: The 2015+5G>A is a novel, likely pathogenic variant in NS. Herein we review and assimilate documented SPINK5 pathogenic variants and discuss possible genotype-phenotype associations in NS.

The Antibiotic Susceptibility Profile of Cutibacterium Acnes in Maltese Patients with Acne.

BACKGROUND: Antibiotics have been widely used for the management of acne vulgaris, which has led to increased resistance of Cutibacterium acnes (C. acnes). OBJECTIVES: We sought to determine the susceptibility profile of C. acnes, isolated from patients with acne, to different prescribed antibiotics and compare our findings with global data. The relationship between antibiotic resistance and sex, age, acne severity, presence of any affected siblings, disease duration, and previous antimicrobial treatment was also investigated. METHODS: Samples were collected from randomly selected pustular acne lesions of patients attending the Dermatology Outpatients Clinic at Sir Paul Boffa Hospital in Floriana, Malta. Samples were inoculated and incubated in anaerobic conditions until 100 cultured C. acnes samples were obtained. Antibiotic susceptibility testing was then performed using azithromycin, clindamycin, doxycycline, minocycline, tetracycline, and trimethoprim/sulfamethoxazole using the agar dilution method. RESULTS: The highest resistance was observed to azithromycin (18%) followed by clindamycin (16%). Resistance to doxycycline and tetracycline was only found in two percent of the isolates and there was no resistance to trimethoprim/sulfamethoxazole and minocycline. Resistance to azithromycin and clindamycin was associated with acne severity (p=0.01 and p=0.03). Resistance to clindamycin was also statistically significantly higher in patients with a history of antibiotic therapy or concurrent antibiotic therapy during the study (p=0.04). CONCLUSION: To our knowledge, this is the first study documenting the susceptibility of C. acnes isolates to different antibiotics in Malta. Future research is needed to determine the clinical significance of antibiotic resistance of C. acnes.

Photoadaptation during narrowband ultraviolet-B therapy is independent of skin type: a study of 352 patients.

Understanding how photoadaptation differs between individuals is important when considering susceptibility to the beneficial and harmful effects of sunlight exposure and when determining optimal phototherapy regimens. Most narrowband UVB (NB-UVB) regimens start with 70% of the minimal erythema dose (MED) with 20% increments at each treatment thereafter. We retrospectively studied 352 skin types I-IV psoriatic patients having twice weekly treatment with this regimen. Patients with high skin types tended to have high MEDs (P<0.001). By session 20 the proportion of patients who had developed erythema was approximately 60% regardless of MED. Among patients who developed erythema, the number of treatments before erythema occurred did not differ between skin types (P=0.33). We conclude that patients with high skin types photoadapt approximately equally per physical unit of UVR in comparison to those with low skin types, but they have greater photoadaptation in absolute terms because they are able to tolerate a higher initial dose of radiation. Differences in skin type or MED are not associated with clinically important differences in tendency to erythema during a standard 70/20% NB-UVB twice-weekly regimen. This regimen is suitable for all skin types I-IV patients regardless of skin type or MED.