Dermatitis®

Abstract: Chemical leukoderma (CL) is an acquired depigmentation condition caused by repeated exposure to melanocytotoxic chemicals that can occur in the presence or absence of allergic contact dermatitis (ACD). Chemicals containing aromatic or aliphatic derivatives such as phenols and catechols have been shown to have melanocytotoxic properties that contribute to the pathogenesis of CL. Lesions are clinically and histologically indistinguishable from vitiligo and can occur in the absence of preexisting inflammatory cutaneous disease or vitiligo. CL often occurs after the use of personal care products or through occupational exposure (such as personal protective equipment). It is a growing phenomenon that has affected patients worldwide and can especially have detrimental psychosocial effects on patients with skin of color because of the sharp contrast between the leukoderma and the background pigmentation of the unaffected skin. A large number of reports of ACD preceding CL in the past five decades suggest that sensitization to allergens containing both aromatic and nonaromatic compounds may be contributory to the development of contact hypersensitivity reaction followed by leukoderma weeks to months after initial exposure. The most commonly reported allergen among these case reports is para-phenylenediamine, an agent used in hair dye and frequently as a darkening agent in henna tattoos. This review provides an overview of the pathophysiology and factors related to CL after ACD or diagnostic patch testing and the allergens related to this disorder of pigmentation.

Abstract: Contact dermatitis (CD), which includes both allergic CD and irritant CD, is a common inflammatory condition that can pose significant diagnostic challenges. Although patch testing is the gold standard for identifying causative allergens for allergic contact dermatitis (ACD), it is time-consuming, subjective, and requires expert interpretation. Recent advancements in artificial intelligence (AI), particularly in machine learning (ML) and deep learning, have shown promise in improving the accuracy, efficiency, and accessibility of CD diagnosis and management.

This review explores current applications of AI in CD, drawing from 12 original studies that investigated AI-based image analysis, biomarker discovery, and patient risk profiling. Convolutional neural networks demonstrated high diagnostic accuracy (up to 99.5%) in interpreting patch test images, while ML algorithms successfully identified transcriptomic signatures distinguishing allergic CD from irritant CD. In addition, AI has been used to predict positive patch test outcomes and identify high-risk patients based on clinical and occupational factors.

Despite these promising developments, limitations such as dataset bias, lack of standardization, and model interpretability remain. Nevertheless, AI represents a transformative tool in dermatology, offering the potential for standardized diagnostics, personalized care, and enhanced accessibility.

Abstract: Nutritional supplements and topical formulations are increasingly implicated in allergic contact dermatitis (ACD), yet their allergenic potential remains underrecognized due to inconsistent regulatory oversight, limited provider awareness, and the misconception that “natural” products are inherently safe. To identify emerging allergens in supplements and cosmetics, characterize associated ACD reactions, and highlight diagnostic and regulatory challenges. A systematic review of PubMed, Embase, MEDLINE, Web of Science, and CENTRAL databases was conducted to evaluate reports of ACD linked to dietary supplements and topical formulations. Key sensitizers include vitamin derivatives (tocopherol, phytonadione, ascorbic acid), herbal extracts (Ginkgo biloba, turmeric, St. John’s Wort), and antioxidants (α-lipoic acid, resveratrol). Documented cases range from localized dermatitis to systemic reactions. Patch testing confirms sensitization, with cross-reactivity and oxidation-related allergenicity frequently observed. Patch testing may not always reveal the sensitizing agent, especially if the allergen is a contaminant, an unlisted ingredient, or undergoes chemical transformation during oxidation or formulation. The rising prevalence of supplement- and cosmetic-induced ACD underscores the need for standardized patch testing, improved ingredient labeling, and enhanced regulatory oversight, including mandated reporting of adverse reactions, premarket safety testing for allergens, and standardized labeling of known sensitizers and botanical components.

Abstract: Atopic dermatitis (AD) is a chronic inflammatory skin disorder that significantly impacts patients’ quality of life. Novel biological agents targeting the OX40 pathway have shown promise in refractory cases. We aimed to systematically evaluate the efficacy and safety of anti-OX40 therapies (amlitelimab, rocatinlimab, and telazorlimab) in moderate-to-severe AD. We systematically searched PubMed, Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL) databases up to January 2025 for clinical trials comparing anti-OX40 therapies with placebo in patients with AD. This study followed Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Five randomized clinical trials were included, comprising 1118 patients, of whom 857 (76.6%) received one of the anti-OX40 therapies. Both high-dose (mean difference [MD] = −17.33; 95% confidence interval [CI] = −23.79 to −10.87; P < 0.001) and low-dose (MD = −16.35; 95% CI = −27.42 to −5.28; P = 0.004) regimens significantly improved the SCORing AD, and multiple other outcomes also showed statistically significant improvements, including reductions in the mean Eczema Area and Severity Index score and body surface area affected by the disease. The incidence of any treatment-emergent adverse event was not statistically significant for either the high-dose group (risk ratio [RR] = 1.14; 95% CI = 0.82–1.59; P = 0.443) or the low-dose group (RR = 1.10; 95% CI = 0.84–1.45; P = 0.486). In conclusion, anti-OX40 therapies demonstrate clinically meaningful efficacy and an acceptable safety profile for moderate-to-severe AD, offering a potential alternative for patients with inadequate responses to current treatments. Further research is warranted to confirm these results and to refine optimal dosing strategies.

Abstract: Dupilumab has emerged as an important treatment for inadequately controlled moderate-to-severe atopic dermatitis (AD). However, joint pain after dupilumab use has prompted the inclusion of arthralgia in the Summary of Product Characteristics of dupilumab. In this article we reviewed arthritis and inflammatory arthropathy as an adverse effect of dupilumab treatment for AD. A comprehensive search was performed for randomized controlled trials, observational studies, case series, and case reports analyzing joint pain prevalence among AD patients treated with dupilumab. This study was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 checklist and quality was assessed via the Newcastle–Ottawa Quality Assessment Scale (NOS). Forty-three studies were included in the systematic review, and 34 studies (15,101 patients) were included in the meta-analysis. Among the 34 studies, the pooled prevalence of joint pain among dupilumab patients was 1.74% (95% confidence interval [CI]: 1.12–2.68). Among the eight studies that reported inflammatory arthropathy prevalence among dupilumab patients, the pooled prevalence of inflammatory arthropathy among dupilumab patients was 2.62% (95% CI: 1.44–4.70). Among the eight studies with a control group, the overall relative risk of developing joint pain after dupilumab use for AD was not significantly higher at 0.68 (95% CI: 0.29–1.58, P = 0.31), compared to the control group. Although our findings found that there is insufficient evidence to suggest that dupilumab use was associated with joint pain, the prevalence of joint pain observed among patients treated with dupilumab may warrant proactive surveillance in clinical practice.

Abstract: Background: Distinguishing between contact urticaria and allergic contact dermatitis can be challenging, and some patients may exhibit a combination of immediate and delayed-type reactions. Patients with suspected contact allergy are often referred to specialized patch testing centers, some of which may not offer contact urticaria testing.

Objective: To examine the role of contact urticaria testing at our institution, specifically analyzing its ability to unveil reactions not detected during standard patch testing.

Methods: Retrospective study of 2,396 patients comprehensively patch tested over a 5-year period. For each allergen in our contact urticaria series, positive reactions were assessed for concordant reactions on standard patch testing. A separate analysis including cross-reactors was conducted for fragrance and benzoate allergens.

Results: Of 31 patients who received both contact urticaria and standard patch testing, 24 exhibited at least 1 positive contact urticaria reaction, amounting to 73 total reactions. 86% (63/73) of these reactions were identified with contact urticaria testing only.

Conclusions: In our experience, contact urticaria testing revealed reactions not demonstrated during standard patch testing. Standardized contact urticaria testing protocols may result in improved diagnosis and disease clearance. Thus, patch testing centers might consider performing contact urticaria testing for patients with immediate-onset symptoms.

Abstract: Background: Extended patch testing beyond the standard series is commonly performed in patients with allergic contact dermatitis. This broader testing allows for more precise and complete allergen identification, ultimately leading to improved clinical outcomes.

Objective: To report the Mayo Clinic Contact Dermatitis Group (MCCDG) patch testing results using a custom extended series from 2010 to 2023.

Methods: A retrospective review of patch testing results using the MCCDG extended standard series at the Mayo Clinic was conducted. Data from 2010 to 2023 were analyzed.

Results: Patch testing with the extended standard series was performed in 3,767 unique patients, with a total of 3834 extended standard patch tests administered (81.8% in women, 18.2% in men). The top 5 allergens eliciting positive reactions were gold (I) sodium thiosulfate (10.4%), benzisothiazolinone (10.4%), carmine (9.4%), thimerosal (9.3%), and hydroperoxides of linalool (8.8%).

Conclusions: The extended standard series expands the diagnostic scope for patients in whom the standard series incompletely identifies relevant allergens. Preservatives and fragrances remain among the most common sensitizers, emphasizing the need for ongoing allergen surveillance, periodic review, and updates to patch test series to enhance diagnostic accuracy and patient care.

Abstract: Background: Hand eczema and hand psoriasis are common skin conditions that may present with similar clinical features, making differentiation challenging.

Objective: This study aims to identify clinical characteristics that distinguish hand eczema from hand psoriasis.

Methods: A retrospective chart review was conducted on patients diagnosed with either condition at the Contact Dermatitis and the Psoriasis Clinic of the Department of Dermatology, Siriraj Hospital, Mahidol University—a national tertiary referral center in Thailand—from January 2015 to November 2022.

Results: A total of 398 patients with hand eczema and 140 with hand psoriasis were included. Exogenous (76.1%) and endogenous (23.9%) hand eczema showed similar lesion location and morphology. However, compared with hand psoriasis, endogenous hand eczema more commonly involved the palmar area, palmar side of digits, and finger pulps (P < 0.001). Conversely, hand psoriasis predominantly affected both sides of the wrist, the dorsal side of the hand, nail fold, and the nails (P < 0.001). Clinical manifestations such as papules, vesicles, scales, and fissures were more frequently observed in endogenous hand eczema, whereas hyperkeratotic plaques were more characteristic of hand psoriasis (P < 0.001). Itching was significantly more frequent in hand eczema (P < 0.001).

Conclusions: Symptoms, lesion locations, and morphology may provide valuable insights that enhance diagnostic accuracy in distinguishing between hand eczema and psoriasis.

Abstract: Background: Some patients with atopic dermatitis (AD) do not sufficiently respond to upadacitinib, a Janus kinase 1 inhibitor. However, predictive factors for nonresponders remain unclear in real-world practice.

Objective: To identify predictive factors for primary and secondary nonresponders to upadacitinib 15 mg; primary nonresponders are defined as patients with investigator’s global assessment (IGA) >2 at week 12, while secondary nonresponders are defined as patients with IGA ≤2 at week 12 and IGA >2 at week 24.

Methods: A prospective study was conducted from August 2021 to March 2024, involving 204 Japanese AD patients treated with upadacitinib 15 mg. Baseline clinical and laboratory indexes were compared between nonresponders and responders.

Results: Primary nonresponders showed higher baseline eczema area and severity index (EASI), immunoglobulin E (IgE), thymus and activation-regulated chemokine (TARC), lactate dehydrogenase (LDH), neutrophil-to-lymphocyte ratio (NLR), C-reactive protein (CRP), systemic immune-inflammation index (SII), and systemic inflammation response index (SIRI) compared with responders. Secondary nonresponders had a higher proportion of previous systemic therapies, dupilumab, and corticosteroids.

Conclusions: Higher baseline EASI, IgE, TARC, LDH, NLR, CRP, SII, and SIRI may predict primary nonresponders to upadacitinib 15 mg, while previous systemic dupilumab or corticosteroids may predict secondary nonresponders.

Abstract: Background: There remains unmet need for therapies for atopic dermatitis (AD) with favorable symptom control but less frequent dosing.

Objective: To evaluate the benefits and safety of MG-K10, a humanized interleukin-4 receptor alpha-targeting antibody, in moderate-to-severe AD.

Methods: In this multi-center, double-blind, randomized, phase II trial, 163 moderate-to-severe AD patients were randomized to receive 16-week treatment with MG-K10 150 mg every 4 weeks (Q4W), 300 mg every 2 weeks (Q2W) (n = 41), 300 mg Q4W (n = 41), or placebo (n = 40). Primary endpoint was the change in Eczema Area and Severity Index (EASI) scores from baseline to week 16.

Results: The mean differences in EASI score at week 16 for the 300 mg Q4W, 300 mg Q2W, and 150 mg Q4W groups were −38.83% (95% confidence interval [CI]: −56.47% to −21.20%, P < 0.001), −27.06% (95% CI: −44.73% to −9.38%, P = 0.003), and −16.00% (95% CI: −33.66% to 1.67%, P = 0.076) compared with placebo group. The proportion of participants achieving EASI-75 at week 16 was 79.5%, 66.7%, 53.8%, and 28.9% in the 300 mg Q4W, 300 mg Q2W, 150 mg Q4W, and placebo groups. The incidence of adverse events was comparable across groups.

Conclusion: MG-K10 demonstrates potential as a long-acting therapeutic option for managing symptoms of moderate-to-severe AD, with favorable safety profile. The preliminary efficacy and safety supported further validation of 300 mg Q4W in phase III trial.

Abstract: Background: Although clinical studies have demonstrated the effectiveness and safety of abrocitinib for moderate to severe atopic dermatitis (AD), real-world evidences are limited. In particular, studies exploring the impact of different treatment modes on prognosis are currently lacking.

Objective: This study aimed to investigate the effects of various abrocitinib treatment regimens on the prognosis of AD.

Methods: A retrospective study was conducted at the Southwest Hospital of the Army Military Medical University and involved patients with moderate to severe AD receiving abrocitinib. After disease control, patients were given the option to continue, taper, or discontinue abrocitinib based on their preferences. Clinical data from eligible patients were retrospectively collected between August 2023 and April 2024.

Results: In the maintenance group (100 mg/day), EASI-75, and pp-NRS4 were achieved by 33.3% and 58.3% of patients, respectively, with a mean reduction of 12.8 points in Dermatology Quality of Life Index (DLQI) compared with baseline. Patients who completed the 12-week induction period (including both maintenance and tapering groups) showed greater improvement in SCORing atopic dermatitis (P < 0.0001; P = 0.0002), Eczema Area and Severity Index (P < 0.0001; P = 0.0002), Peak Pruritus Numerical Rating Scale (all P < 0.0001), and DLQI (all P < 0.0001), as well as a longer time to relapse, compared to those in the discontinuation group.

Conclusion: Continuous treatment with abrocitinib and completion of the 12-week induction period were associated with improved outcomes and reduced relapse rates in AD patients.

Abstract: Background: Stapokibart has been approved for the treatment of adults with atopic dermatitis (AD) in China.

Objective: To report long-term efficacy of stapokibart in patients with moderate-to-severe AD.

Methods: This post hoc analysis included 237 adult patients from a phase 3 trial (NCT05265923) who received stapokibart 300 mg (loading dose, 600 mg) every 2 weeks during the 16-week double-blind period and continued with the same dose of stapokibart in the subsequent 36-week maintenance period.

Results: At week 20, 100% and 92.2% of patients who achieved coprimary endpoints (≥75% improvement in Eczema Area and Severity Index [EASI-75] and Investigator’s Global Assessment [IGA] 0/1 response) at week 16 retained their EASI-75 and IGA 0/1 response, respectively. At week 52, these figures reached 99.0% and 87.0%, respectively. Among those who had not achieved EASI-75 or IGA 0/1 at week 16, 65.4% achieved EASI-75 and 18.1% achieved IGA 0/1 at week 20, and reached 86.8% and 50.0% at week 52, respectively. The patient-reported outcomes also improved sustainedly.

Conclusions: Long-term stapokibart treatment induced sustained clinical improvements in adult patients with moderate-to-severe AD, regardless of their initial response to 16-week treatments.