Association of Countries' Atopic Dermatitis Burden and Sociodemographic Index with Topical Calcineurin Inhibitor Utilization.

Background: There is limited knowledge on international trends in topical calcineurin inhibitor (TCI) utilization. Objective: To describe international TCI utilization trends from 2012 to 2019 and evaluate the relationship of country-level economic status, geographic location, and atopic dermatitis (AD) disease burden with drug utilization. Methods: We used IQVIA MIDAS® pharmaceutical quarterly sales data to attain country-level purchasing of TCIs in grams from 2012 to 2019. A multivariable linear regression estimated the association between countries' sociodemographic index (SDI), AD disability-adjusted life year (DALY) rates, and geographic location with TCI utilization. Results: A total of 68 countries were included in our analysis. From 2012 to 2019, overall TCI utilization increased by 66% but remained 11.2 times higher in high-sociodemographic compared with low-middle/low-sociodemographic countries. SDI and geographic location were associated with greater TCI utilization in multivariable analyses, whereas AD DALY rates were not. High-SDI countries used 21,476 grams (95% confidence interval [CI]: 11,915 to 31,036) and high-middle SDI countries used 9,403 grams (95% CI: -393 to 19,200) more TCIs per 100,000 people compared with low-middle/low-SDI countries, respectively. Northern hemisphere countries used 8,588 grams more TCIs per 100,000 people (95% CI: 612 to 16,564). Conclusions: We demonstrated greater TCI utilization among high-SDI compared with lower SDI countries.

Upregulation of caveolae-associated structural proteins in the hair follicle bulge of lichen planopilaris and frontal fibrosing alopecia.

Lichen planopilaris (LPP) and frontal fibrosing alopecia (FFA) are primary cicatricial alopecia that cause a major impact on quality of life due to irreversible hair loss and symptoms as itching, burning and pain. They are characterized by permanent loss of hair follicle stem cells (HFSCs) by pathomechanisms still poorly understood, resulting in poor efficacy of currently available treatments. Caveolae are flask-shaped lipid rafts invaginated within the plasma membrane of multiple cell types. Although their role in the HF physiology and pathophysiology is relatively unknown, we have previously demonstrated that the primary structural component of caveolae (caveolin-1 or Cav1) is upregulated in FFA. Thus, we propose to investigate the expression and localization of caveolae-associated structural proteins (Cav1, Cav2, and Cavin-1) and HFSCs (identified by K15) in both LPP and FFA. We analyzed 4 patients with LPP biopsied in affected and non-affected (NA) scalp, 4 patients with FFA biopsied in affected scalp and 4 healthy controls. Affected scalp of LPP and FFA demonstrated increased levels of Cav1 and Cavin-1 compared with HC and LPP-NA. Moreover, Cav1, Cav2 and Cavin1 all exhibit high colocalization with K15 and their expression appears to be negatively correlated, supporting the hypothesis that these proteins are important players in LPP/FFA and may serve as therapeutic targets in future treatments.

Patient-reported burden in adults with atopic dermatitis: an international qualitative study.

The objective was to study a large, international, ethnically diverse population of patients with atopic dermatitis (AD) to support the creation of patient-centric recommendations for AD management. Qualitative data were generated from 45-min, 1:1 telephone interviews conducted across 15 countries in each patient's native language. Interviews explored the impact of AD on patients' lives, patients' most important symptoms, treatment expectations, and treatment decision-making. Participants were also questioned on their current knowledge of AD scoring systems and what was most important to include in these tools. In total, 88 adult patients (≥ 18 years old) receiving treatment for AD were recruited through a market research database, clinician referrals, and local advertising. All patients were screened to ensure a balanced and diverse sample in terms of age, gender, educational level, employment status, geographic location, and AD severity. Patients involved in market research or activities supporting advocacy groups within the previous 6 months or affiliated with or employed by pharmaceutical companies were excluded. AD had a substantial impact on patients' lives. Itch, skin redness, and dry/flaky skin were the most frequently reported symptoms, with > 75% of patients experiencing these symptoms every 1-3 days. Mental health issues were common and resulted in the greatest negative impact on patients' daily lives. Patients perceived clinicians to underestimate the burden of their AD. Patients had little awareness of AD scoring systems and indicated a preference for these to be more clearly incorporated in clinical practice. For an ideal scoring system, patients favored using a combination of patient-reported and clinician-reported outcomes to reflect disease burden and ensure consistency across all settings. This global study generated diverse patient perspectives on the disease burden of AD, their expectations of treatment, and their views on AD scoring methods. These data provide evidence to support the development of patient-centric recommendations for AD management.

Cutaneous inflammasome driving ASC / gasdermin-D activation and IL-1ß-secreting macrophages in severe atopic dermatitis.

Atopic dermatitis (AD) is an inflammatory skin disease with intense pruritus, and chronic skin colonization by Staphylococcus aureus. To understand the inflammatory status in AD, we investigated the inflammasome complex, that activates ASC (Apoptosis-associated speck-like protein containing a CARD), caspase-1 and GSDMD (gasdermin-D), and production of IL-1ß and IL-18. We aimed to evaluate the expression of the inflammasome pathway in the skin of adults with AD. Thirty patients with moderate to severe AD and 20 healthy controls were enrolled in the study. We performed the analysis of the inflammasome components NLRP1, NLRP3, AIM-2, IL-1ß, IL-18, Caspase-1, ASC, GSDMD, and CD68 expression (macrophage marker) by immunohistochemistry and immunofluorescence. The main findings included increased expression of NLRP3, NLRP1 and AIM-2 at dermal level of severe AD; augmented IL-18 and IL-1ß expression at epidermis of moderate and severe patients, and in the dermis of severe AD; augmented expression of ASC, caspase-1 and GSDMD in both epidermis and dermis of moderate and severe AD. We detected positive correlation between caspase-1, GSDMD and IL-1ß (epidermis) and caspase-1 (dermis) and AD severity; NLRP3, AIM-2 and IL-1ß, and NLRP3 with IL-18 in the epidermis; ASC, GSDMD and IL-1ß, and NLRP3, AIM-2, caspase-1, and IL-18 in the dermis. We also evidenced the presence of CD68+ macrophages secreting GSDMD, ASC and IL-1ß in moderate and severe AD. Cutaneous macrophages, early detected in moderate AD, have its role in the disease inflammatory mechanisms. Our study indicates a canonical activation pathway of inflammasomes, reinforced by the chronic status of inflammation in AD. The analysis of the inflammasome complex evidenced an imbalance in its regulation, with increased expression of the evaluated components, which is remarkably in severe AD, emphasizing its relevance as potential disease biomarkers and targets for immunomodulatory interventions.

International time trends and differences in topical actinic keratosis therapy utilization.

Background: Actinic Keratoses (AK) are precancerous lesions that can lead to Squamous Cell Carcinoma. International differences in the utilization of topical medications to treat AK are not well described. Objectives: To describe international differences in topical AK medication utilization, including associations of countries' economic status with AK medication utilization. Methods: We used IQVIA MIDAS pharmaceutical sales data for 65 countries (42 high-income, 24 middle-income) from April 2011 to December 2021. We calculated each country's quarterly utilization of medications in grams per 1000 population. We used univariable linear regression to assess the association between country economic status and AK medication utilization. Results: High-income countries used 15.37 more grams per 1000 population of 5-fluorouracil (95% CI: 9.68, 21.05), 4.64 more grams per 1000 population of imiquimod (95% CI: 3.45, 5.83), and 0.32 more grams per 1000 population of ingenol mebutate (95% CI: 0.05, 0.60). Limitations: Missing medication utilization data for some countries. Conclusion: High-income countries use more topical AK therapies than middle-income countries.

State of the Art on the Role of Staphylococcus aureus Extracellular Vesicles in the Pathogenesis of Atopic Dermatitis.

Atopic dermatitis (AD) is a chronic and relapsing inflammatory cutaneous disease. The role of host defense and microbial virulence factors in Staphylococcus aureus skin colonization, infection, and inflammation perpetuation in AD remains an area of current research focus. Extracellular vesicles (EV) mediate cell-to-cell communication by transporting and delivering bioactive molecules, such as nucleic acids, proteins, and enzymes, to recipient cells. Staphylococcus aureus spontaneously secretes extracellular vesicles (SA-derived EVs), which spread throughout the skin layers. Previous research has shown that SA-derived EVs from AD patients can trigger cytokine secretion in keratinocytes, shape the recruitment of neutrophils and monocytes, and induce inflammatory AD-type lesions in mouse models, in addition to their role as exogenous worsening factors for the disease. In this review article, we aim to examine the role of SA-derived EVs in AD physiopathology and its progression, highlighting the recent research in the field and exploring the potential crosstalk between the host and the microbiota.

Outlining the skin-homing and circulating CLA+NK cells in patients with severe atopic dermatitis.

Atopic dermatitis (AD) is a complex, multifactorial skin disease, characterized by pruritus and predominant Th2 inflammation. Innate immune cells may play a role in AD development and are composed of granulocytes, macrophages, innate-like T cells, and innate lymphoid cells. This study investigates the phenotypic and functional profile of circulating CLA+ natural killer (NK) cells and its role in the skin-homing to NK cells infiltrated in adults' skin with AD. We selected 44 AD patients and 27 non-AD volunteers for the study. The results showed increased frequencies of both CLA+CD56bright and CLA+CD56dim NK cell populations in the peripheral blood, mainly in severe AD patients. Upon SEB stimulation, we observed an augmented percentage of CLA+CD56dim NK cells expressing CD107a, IFN-γ, IL-10, and TNF, reinforcing the role of staphylococcal enterotoxins in AD pathogenesis. Additionally, we demonstrated increased dermal expression of both NK cell markers NCAM-1/CD56 and pan-granzyme, corroborating the skin-homing, mostly in severe AD. Further studies are necessary to elucidate the potential role of NK cells in the chronification of the inflammatory process in AD skin, as well as their possible relationship with staphylococcal enterotoxins, and as practicable therapeutic targets.

Methotrexate for refractory adult atopic dermatitis leads to alterations in cutaneous IL-31 and IL-31RA expression

Abstract Background: Methotrexate (MTX) is an alternative treatment for patients with moderate/severe atopic dermatitis (AD). Objective: The authors evaluated the effect of MTX on the cutaneous expression of cytokines and chemokines that are involved in the inflammatory response in adult AD patients who received treatment with methotrexate for 24 weeks. Methods: The authors conducted a prospective single-institution cohort study with 12 adults with moderate/severe AD who received oral MTX (15 mg/wk for 24 wks) and 10 non-atopic matched controls. The comparison was made of skin biopsies of lesional and non-lesional skin, pre- and post MTX treatment. The authors analyzed mean epidermal thickness and expression of IL-31, IL-31RA, OSMR, TSLP, Ki67, IL-4 mRNA, IL-6, IL-10, TNF-α, IFN-γ, TARC, and CCL-22. Results: There was a reduction in mean epidermal thickness (p = 0.021), an increase in IL-31RA expression (immunohistochemistry) in the epidermis (p = 0.016) and a decrease in IL-31 gene expression (p = 0.019) on lesional AD skin post-MTX treatment. No significant changes in the cutaneous expression of the other evaluated markers were identified. Study limitations: Small sample size and limited length of follow-up. Conclusions: Treatment with MTX in adults with moderate/severe AD reduced epidermal hyperplasia and changed the cutaneous expression of inflammatory cytokines and receptors that are mainly related to pruritus, including IL-31 and IL-31RA.

Impact of climate change on atopic dermatitis: A review by the International Eczema Council.

Atopic dermatitis (AD), the most burdensome skin condition worldwide, is influenced by climatic factors and air pollution; however, the impact of increasing climatic hazards on AD remains poorly characterized. Leveraging an existing framework for 10 climatic hazards related to greenhouse gas emissions, we identified 18 studies with evidence for an impact on AD through a systematic search. Most climatic hazards had evidence for aggravation of AD the impact ranged from direct effects like particulate matter-induced AD exacerbations from wildfires to the potential for indirect effects like drought-induced food insecurity and migration. We then created maps comparing the past, present, and future projected burden of climatic hazards to global AD prevalence data. Data are lacking, especially from those regions most likely to experience more climatic hazards. We highlight gaps important for future research: understanding the synergistic impacts of climatic hazards on AD, long-term disease activity, the differential impact on vulnerable populations, and how basic mechanisms explain population-level trends.

Real-world clinical, psychosocial and economic burden of atopic dermatitis: Results from a multicountry study.

BACKGROUND: Atopic dermatitis (AD), a relapsing, inflammatory skin disease, is associated with pruritus that can negatively affect patients' quality of life. Understanding the burden of AD is critical for informing and tailoring treatment and disease management to improve patient outcomes. This study characterized global treatment patterns and the clinical, psychosocial and economic burden of moderate-to-severe AD. METHODS: MEASURE-AD was a cross-sectional 28-country study in patients with physician-confirmed moderate-to-severe AD who were either receiving or eligible for systemic therapy for AD. Patients ≥12 years were enrolled between December 2019 and December 2020 while attending routine office or clinic visit. Primary outcomes included Worst Pruritus Numeric Rating Scale (WP-NRS; range: 0-10) and Dermatology Life Quality Index (DLQI; range: 0-30) and Children's DLQI (CDLQI; range: 0-30). Secondary outcomes included physician- and patient-reported clinical, psychosocial and economic burden. RESULTS: Of the 1591 patients enrolled, 1558 (1434 adults and 124 adolescents) fulfilled all patient selection criteria and were included in this analysis. Almost all patients (98.4%) in the total population were using AD medications and more than half (56%) were receiving systemic medication (15% systemic monotherapy). The most used systemic therapies were dupilumab (56.3%), systemic glucocorticoids (18.1%) and methotrexate (16.2%). Mean WP-NRS was 5.3 in the total population, and most patients (≥55%) reported moderate-to-severe pruritus (WP-NRS ≥4). Mean DLQI was 10.8 and mean CDLQI was 9.6. Secondary endpoints demonstrated substantial clinical, psychosocial, and economic burden of disease. Subgroup analysis demonstrated that patients receiving systemic therapy had lower disease burden than those not taking systemic medications. CONCLUSIONS: While systemic therapy lowers overall disease burden, patients with moderate-to-severe AD continue to have substantial multidimensional disease burden and uncontrolled disease. Overall, there is a need for effective disease management, including effective treatments that improve patients' psychosocial outcomes and reduce the economic burden of AD.

Methotrexate for refractory adult atopic dermatitis leads to alterations in cutaneous IL-31 and IL-31RA expression.

BACKGROUND: Methotrexate (MTX) is an alternative treatment for patients with moderate/severe atopic dermatitis (AD). OBJECTIVE: The authors evaluated the effect of MTX on the cutaneous expression of cytokines and chemokines that are involved in the inflammatory response in adult AD patients who received treatment with methotrexate for 24 weeks. METHODS: The authors conducted a prospective single-institution cohort study with 12 adults with moderate/severe AD who received oral MTX (15 mg/wk for 24 wks) and 10 non-atopic matched controls. The comparison was made of skin biopsies of lesional and non-lesional skin, pre- and post MTX treatment. The authors analyzed mean epidermal thickness and expression of IL-31, IL-31RA, OSMR, TSLP, Ki67, IL-4 mRNA, IL-6, IL-10, TNF-α, IFN-γ, TARC, and CCL-22. RESULTS: There was a reduction in mean epidermal thickness (p = 0.021), an increase in IL-31RA expression (immunohistochemistry) in the epidermis (p = 0.016) and a decrease in IL-31 gene expression (p = 0.019) on lesional AD skin post-MTX treatment. No significant changes in the cutaneous expression of the other evaluated markers were identified. STUDY LIMITATIONS: Small sample size and limited length of follow-up. CONCLUSIONS: Treatment with MTX in adults with moderate/severe AD reduced epidermal hyperplasia and changed the cutaneous expression of inflammatory cytokines and receptors that are mainly related to pruritus, including IL-31 and IL-31RA. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03327116.

Consensus on the therapeutic management of atopic dermatitis ‒ Brazilian Society of Dermatology: an update on phototherapy and systemic therapy using e-Delphi technique.

This publication is an update of the "Consensus on the therapeutic management of atopic dermatitis - Brazilian Society of Dermatology" published in 2019, considering the novel, targeted-oriented systemic therapies for atopic dermatitis. The initial recommendations of the current consensus for systemic treatment of patients with atopic dermatitis were based on a recent review of scientific published data and a consensus was reached after voting. The Brazilian Society of Dermatology invited 31 experts from all regions of Brazil and 2 international experts on atopic dermatitis who fully contributed to the process. The methods included an e-Delphi study to avoid bias, a literature search and a final consensus meeting. The authors added novel approved drugs in Brazil and the indication for phototherapy and systemic therapy for AD. The therapeutical response to systemic treatment is hereby reported in a suitable form for clinical practice and is also part of this updated manuscript.

Atopic Dermatitis in Latin America: Considerations on Epidemiology, Clinical and Laboratory Features, Ethnic/Racial Variations, and Therapeutic Management.

Latin America (LA) encompasses about 8.5% of the world's population, exhibits ethnic/racial heterogeneity and social inequality. We hereby present a 20-year literature review (2004-2023) on epidemiology, diagnosis, clinical and laboratory features, quality of life and management of atopic dermatitis (AD) in LA. Highest AD prevalence for children aged 6-7 years was reported in Ecuador (22.5%) and Colombia (20.9%), for adolescents in Colombia (24.6%) and for all ages, in Brazil (20.1%). Regions with a predominantly Black population in LA varied significantly, ranging from 4.4% in Northern Brazil to 10.1% in Cuba, indicating genetic variation among African subgroups. Filaggrin loss-of-function mutations showed variants seen in Europeans in 9.3% of Chilean patients and studies in Brazil revealed impaired expression of filaggrin and claudin-1 in the skin but increased expression in conjunctival epithelia of AD patients. The most reported AD features included erythema, pruritus, and dry skin, with marked lichenification. Severe pruritus was reported by 54.4% of patients and a high impact on quality of life was detected in 50% of adults with AD. In Brazilian referral hospitals, 65.6% of patients were classified as having severe AD, and 56% had one or more hospitalizations during their lifetime, indicating a need for better disease control. Diagnosing AD is challenging due to broad clinical features, ethnoracial variations and lack of universal diagnostic criteria. Furthermore, lack of physician training, barriers to medication access, and socioeconomic inequalities hinder effective disease management in LA.

Blockage of the IL-31 Pathway as a Potential Target Therapy for Atopic Dermatitis.

Atopic dermatitis (AD), a pruritic, inflammatory chronic disease with multifactorial pathogenesis, has been a therapeutic challenge. Novel target treatments aim to reduce not only the immunologic dysfunction and microbiome dysbiosis but also the recovery of the damaged skin barrier. The current review focuses on the interleukin 31 (IL-31) pathway and AD and offers an overview of the current clinical studies with monoclonal antibodies blocking this cascade. Pruritus, the key symptom of AD, has substantial participation of the IL-31 complex and activation of relevant signaling pathways. Epidermal keratinocytes, inflammatory cells, and cutaneous peripheral nerves express the interleukin-31 receptor α-chain (IL-31RA), upregulated by Staphylococcus aureus toxins or Th2 cytokines involved in AD. Nemolizumab is a humanized monoclonal antibody that antagonizes IL-31RA, inhibiting the IL-31 cascade and therefore contributing to reducing the pruritus and inflammation and recovering the damaged skin barrier in AD patients. Phases 2 and 3 clinical trials with nemolizumab in AD show a suitable safety profile, with a fast, efficient, and sustained reduction of pruritus and severity scores, especially when associated with topical treatment. Deciphering the full interplay of the IL-31 pathway and AD may expand the potential of nemolizumab as a targeted therapy for AD and other pruritic conditions.