The global burden of chronic urticaria for the patient and society*

Exploring the association between urticaria subtypes, anxiety, and depression and potential role of gut microbiota

AIMS

In observational studies, the causal relationship between urticaria and the risk of psychiatric disorders (anxiety and depression) remains inconclusive. Furthermore, there is growing evidence that gut microbiota (GM) contributes to the pathogenesis of urticaria. This study aimed to assess the causal relationships between the genetically predicted urticaria subtypes and psychiatric disorders and further examined the role of GM in influencing the risk of these urticaria subtypes.

METHODS

We conducted a meta-analysis of observational studies identified from four databases to evaluate the associations between urticaria, anxiety, and depression over the past decade. In addition, we estimated the genetic correlation and causality between genetically predicted urticaria subtypes and psychiatric disorders using linkage disequilibrium score regression and Mendelian Randomization (MR) analyses. Finally, univariable two-sample MR and multivariable MR analyses were employed to evaluate the combined and independent effects of GM from two datasets on urticaria subtypes associated with psychiatric disorders.

RESULTS

Thirteen observational studies comprising 7321 participants were included in the meta-analysis. There was a positive association between urticaria and anxiety risk (n = 13, OR: 3.96; 95%CI: 2.90-5.41) as well as depression risk (n = 12, OR: 3.03; 95%CI: 2.30-4.01). The MR results indicated that idiopathic urticaria increased the risk of anxiety (OR = 1.14; 95%CI = 1.01-1.28; P = 3.31 × 10-2), while allergic urticaria increased the risk of major depressive disorder (OR = 1.07; 95%CI = 1.02-1.13; P = 6.65 × 10-3). Our analysis identified nineteen gut bacterial taxa that were causally associated with idiopathic and allergic urticaria. Notably, Intestinibacter and Victivallales were strongly associated with an increased risk of allergic urticaria, even after accounting for the effect of smoking or alcohol consumption in the multivariable MR analysis. FamilyXIIIAD3011group and Bacteroides vulgatus were found to exert protective roles in idiopathic urticaria.

CONCLUSIONS

The study provides evidence for the association between urticaria subtypes and psychiatric disorders, complementing existing observational studies. In addition, our study implies the involvement of gut microbiota in idiopathic and allergic urticaria. However, the specific mechanisms of bacterial action remain to be clarified.

Astrocytic LCN2 drives uremic pruritus and morphine-induced pruritus via the GRP/GRPR pathway

BACKGROUND

Uremic pruritus (UP) is a distressing condition in hemodialysis patients with unclear mechanisms. This study investigates the role of LCN2 in pruritus, focusing on its interaction with GRP/GRPR signaling and astrocyte activation.

METHODS

Clinical skin biopsy samples from CKD patients with and without UP were analyzed for LCN2 expression. A chronic renal failure mouse model (UP model) was established through surgical kidney ablation, while a morphine-induced itch model was generated via intrathecal morphine injection. LCN2 knockout (LCN2-/-) mice were used to evaluate its functional role in itch modulation. Scratching behavior was recorded, and Western blot, qRT-PCR, immunohistochemistry, immunofluorescence, and ELISA were performed to assess LCN2 expression, GRP/GRPR signaling, and inflammatory cytokines in the spinal cord. Additionally, RC-3095 (a GRPR inhibitor) and GRP were administered to evaluate their effects on pruritus.

RESULTS

LCN2 expression was elevated in CKD patients with UP and positively correlated with itch severity. Similarly, UP model mice showed increased spinal LCN2 levels, while LCN2 deficiency (LCN2-/- mice) reduced scratching behavior. Mechanistically, LCN2 promoted pruritus by enhancing GRP/GRPR signaling and astrocyte activation. Blocking GRP/GRPR with RC-3095 reduced pruritus in both UP and morphine-induced models, confirming LCN2's role in itch transmission.

CONCLUSION

LCN2 mediates pruritus by promoting GRP/GRPR signaling, astrocyte activation, and neuroinflammation, making it a potential therapeutic target for CKD-related and opioid-induced pruritus.

Allergic rhinitis and urticaria burden and antihistamine treatment options in Thailand: A modified Delphi study

Background

Allergic rhinitis (AR) and chronic urticaria impose significant socioeconomic burdens on lower-income countries. Despite the availability of evidence-based guidelines, their implementation varies, and comprehensive data on these allergic conditions are notably lacking in Thailand.

Objectives

We sought to describe current management strategies for AR and urticaria in Thailand.

Methods

The Allergy, Asthma, and Immunology Association of Thailand used a modified Delphi method to explore consensus on management strategies for AR and urticaria. Clinicians with expertise in these conditions provided input through a web-based questionnaire. The survey assessed disease burden in Thailand, its impact on quality of life, and the use of H1-antihistimine treatment options.

Results

In total, 105 experts, mainly in allergy and immunology, with 70% having more than 10 years of clinical practice, provided input. Consensus was achieved on 22 (88%) of the 25 statements. Second-generation antihistamines were preferred as initial treatment for AR and urticaria because of their reduced sedation and lack of anticholinergic effects. Almost all participants (98.1%) recommended these antihistamines for acute and chronic urticaria. Additionally, 87.6% of the respondents favored up-dosing a single antihistamine agent for managing chronic urticaria. The benefits of orally disintegrating antihistamines were particularly noted for their ease of administration and patient compliance.

Conclusion

Results indicate a knowledge gap in evidence-based practices among Thai clinicians. Addressing this gap through enhancing clinical guideline adherence and encouraging pharmacist involvement in patient care can improve access to medication and better disease management, ultimately improving patient outcomes while reducing the socioeconomic burden of AR and urticaria.

Biological and target synthetic treatments for chronic spontaneous urticaria: A systematic review and network meta-analysis

BACKGROUND

Most biological and synthetic target-specific drugs for antihistamine-refractory chronic spontaneous urticaria (CSU) have not been compared head-to-head. This systematic review and network meta-analysis evaluated their relative efficacy and safety.

METHODS

Searches were conducted on PubMed, Embase, Web of Science and Cochrane library databases to March 25, 2024 for randomized trials. A random-effects model was used to calculate the network estimates reported as mean differences (MD) and odds ratios (OR) with corresponding 95% CIs. Main outcomes included the weekly urticaria activity score (UAS7), adverse events (AEs) and serious adverse events (SAEs).

RESULTS

23 randomized clinical trials with 6933 participants that compared 26 different interventions or dosages and placebos were included. Omalizumab 300 mg [MD -10.07, 95% CI (-11.35; -8.82)] continues to demonstrate superior efficacy compared with placebo. Remibrutinib, at doses of 35 mg once daily [MD -7.80, 95% CI (-12.76; -2.51)], 25 mg twice daily [MD -7.69, 95% CI (-9.85; -5.76)], and 10 mg twice daily [MD -7.61, 95% CI (-12.59; -2.47)], had the best overall performance for efficacy and safety. Dupilumab, fenebrutinib, and rilzabrutinib also showed greater efficacy than placebo. The results were similar for the proportion of patients who achieved UAS7 ≤ 6 or UAS7 = 0. No significant differences were found among all treatment comparisons for AEs and SAEs.

CONCLUSION

The findings of this study indicate that the biological agent omalizumab 300 mg and the oral small molecule remibrutinib at doses of 35 mg, 25 mg, or 10 mg are recommended for patients with antihistamine-refractory CSU.

TRIAL REGISTRATION

PROSPERO: CRD42024516289.

Cluster Analysis of Clinical Remission and Relapse Patterns in Chronic Urticaria: Results from the PREDICT-CU Study

INTRODUCTION

Patients with chronic urticaria (CU) may have different clinical courses of disease including periods of active CU, clinical remission, and relapse. The objective of this study was to describe representative clinical remission and relapse profiles for patients with CU.

METHODS

Adults with a CU diagnosis and confirmation CU diagnosis/CU-related treatment at least 6 weeks later were identified in the Optum® de-identified Electronic Health Record dataset (2007-2018). Active CU was a period during which a patient was not in clinical remission. Clinical remission was defined as at least 12 months without CU diagnosis and/or treatment. Relapse was defined as having a CU diagnosis and/or treatment following clinical remission. A data-driven clustering algorithm grouped patients on the basis of clinical remission and relapse patterns.

RESULTS

The 112,443 patients were grouped into four clusters. Cluster 1 (N = 36,690 [32.6%]) had the shortest median time to clinical remission (4.1 months) and lowest relapse rate (38.0%). Cluster 2 (N = 29,834 [26.5%]) reached clinical remission later (10.0 months), with a higher relapse rate (52.3%). Clusters 3 (N = 24,093 [21.4%]) and 4 (N = 21,826 [19.4%]) had the longest median times to clinical remission (33.8 and 44.6 months) and highest relapse rates (75%). Cluster 4 had the most frequent CU diagnoses and treatments, and highest comorbidity burden, polypharmacy, and resource use.

CONCLUSIONS

Patients in Clusters 3 and 4 had the lowest clinical remission and highest relapse rates relative to Clusters 1 and 2; additionally, Cluster 4 had higher resource use, more comorbidities, and polypharmacy. These cluster definitions could be used to develop a model to predict patients with relapsing and remitting patterns associated with higher disease burden who might require enhanced disease management.

Update on the Treatment of Chronic Spontaneous Urticaria

Chronic spontaneous urticaria (CSU) is a mast cell-mediated skin disease that presents with wheals, angioedema, or both for more than 6 weeks. Less than 10% of patients have complete control of their CSU (the main goal of CSU treatment) with second generation H1-antihistamines, the first-line treatment. About 70% of patients with antihistamine-refractory CSU do not reach complete control with omalizumab, the second-line treatment. Novel therapies are especially needed for patients with mast cell-activating immunoglobulin (Ig)G autoantibodies (autoimmune CSU) associated with nonresponse or late response to omalizumab. Furthermore, there is a lack of disease-modifying treatments that induce long-term CSU remission after drug withdrawal. Several emerging treatments can address these unmet needs including Bruton tyrosine kinase inhibitors, e.g., remibrutinib and rilzabrutinib; anti-KIT monoclonal antibodies, e.g., barzolvolimab; and anti-cytokine therapies, e.g., dupilumab. In clinical trials, 30-31%, 28-32%, and 38-51% of patients with CSU showed complete response to treatment with dupilumab (phase 3, week 24), remibrutinib (phase 3, week 24), and barzolvolimab (phase 2, week 12), respectively. The most common adverse events were injection site reactions for dupilumab (12%), respiratory tract infections (11%), headache (6%), and petechiae (4%) for remibrutinib and changes in hair color (14%), neutropenia / decreased neutrophil count (9%) and skin hypopigmentation (1%) for barzolvolimab. This review provides an update on the current state of development of treatments for CSU.

Urticaria in China: incidence, prevalence, and disability-adjusted life years compared with G20 countries: findings from the Global Burden of Disease study 2021

Urticaria has become a major public health challenge in China, yet comprehensive national data assessments are lacking. This study analyzes the burden of urticaria in China compared to G20 countries from 1990 to 2021. Using data from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021, we examined the incidence, prevalence, and disability-adjusted life years (DALYs) of urticaria by age and sex in China. Temporal trends were assessed using Average Annual Percent Change (AAPC) estimates. We also decomposed the changes in new cases, patient numbers, and urticaria burden in G20 countries and globally from 1990 to 2021. In 2021, China reported 17.30 million (95% uncertainty interval, 15.37-19.25) new cases of urticaria, 9.87 million (8.72-10.99) existing cases of urticaria, and 0.59 million (0.39-0.82) DALYs due to urticaria, ranking second among G20 countries. These metrics peaked in females under 5 years old. Age-standardized rates in China were lower than the global average and remained stable from 1990 to 2021. The under-5 age group showed the fastest growth in prevalence and DALY rates. The number of urticaria patients increased by 8.52%, with population growth contributing 19.86%, aging - 11.31%, and age-specific prevalence - 0.03%. Despite stable age-standardized rates, the absolute burden of urticaria in China has risen, particularly among females under 5 years old, highlighting the need for targeted public health interventions. Improving public emergency awareness and response is critical for urticaria patients, who may develop severe systemic diseases and fatal allergic symptoms.

Beyond the itch: the complex interplay of immune, neurological, and psychological factors in chronic urticaria

Chronic urticaria (CU) arises from a multifaceted interplay of immunological, neurological, and psychological components. Immune dysregulation, mediated through both immunoglobulin E (IgE)-dependent and IgE-independent pathways, plays a pivotal role in CU pathogenesis, involving key effector cells such as mast cells (MCs), basophils, and eosinophils. This dysregulation culminates in the release of histamine, prostaglandins, and other mediators, which precipitate pruritus. The chronicity of the disease leads to sustained pruritic symptoms, contributing to both central and peripheral sensitization. The excitation of the itch circuit is augmented, leading to the release of neurotransmitters and neuropeptides, which subsequently interact with immune cells. Psychological factors such as depression, anxiety, and stress exacerbate CU symptoms and diminish quality of life. These factors disrupt the hypothalamic-pituitary-adrenal (HPA) axis and the autonomic nervous system (ANS). Furthermore, the act of scratching activates the reward circuit, resulting in the manifestation of the itch-scratching cycle. Current treatments, such as antihistamines, omalizumab, and cyclosporine, demonstrate variable efficacy and are often associated with adverse effects. A holistic approach addressing both psychological and physiological aspects is advocated. This review highlights the critical importance of understanding neuroimmune interactions and the influence of psychosomatic factors in CU. It aims to enhance diagnostic and therapeutic strategies by integrating psychological, neurological, and immunological perspectives.

The Role of Coagulation/Fibrinolysis Biomarkers in Pathophysiology, Disease Severity, and Treatment Response in Patients with Urticaria: A Scoping Review

The pathology of urticaria is complex. Recently, researchers have widely focused on the role that the coagulation/fibrinolysis system plays in the pathology of urticaria. The potential of coagulation/fibrinolysis biomarkers as disease severity or treatment response biomarkers remains uncertain, lacking comprehensive analysis in previous studies. Hence, we performed a scoping review to thoroughly analyze coagulation/fibrinolysis biomarkers that may predict disease progression and treatment response of urticaria. Data from 71 studies showed that chronic spontaneous urticaria (CSU) was the most-studied subtype (39 articles), with D-dimers being the most researched marker (56 articles). Twenty-one biomarkers were investigated, and ten biomarkers were significantly correlated with disease severity. Specifically, D-dimers (26 articles) and prothrombin fragment 1 + 2 (F1+2) (12 articles) plasma levels increased with exacerbation and decreased with remission. Biomarkers such as D-dimer also correlated significantly with inflammatory cytokines and complement, suggesting interactions among coagulation, immunity, and inflammation in the pathology of urticaria. While these biomarkers may predict treatment response, more evidence is needed. Additionally, anticoagulants such as warfarin, heparin sodium and tranexamic acid have been proved effective for urticaria. This review emphasizes that some coagulation/fibrinolysis biomarkers (such as D-dimer and F1+2) may be not only indicators of disease status but also potential predictors of treatment response. It aims to assist researchers and practitioners in gaining a better understanding of the close relationships among coagulation/fibrinolysis biomarkers, the condition of urticaria (especially chronic urticaria, CU), and its prognosis. It also provides new directions for future research on exploring treatment methods via the coagulation/fibrinolysis pathways.

MRI-based neuroimaging alterations in immune-related skin diseases: a comprehensive review

The skin, as the largest organ in the human body, serves as the primary physical barrier and plays a crucial role in the immune defense process. Immune-related skin diseases encompass a spectrum of complex dermatological conditions characterized by aberrant immune responses, including the production of autoantibodies and dysregulation of inflammatory mediators. Growing evidence suggest a heightened prevalence of comorbid neuropsychiatric disorders among patients with immune-related skin diseases, indicative of potential shared pathogenesis. In recent years, the brain connectome, delineating the intricate network of neural connections, has gained prominence in elucidating various neurological and psychiatric conditions. Researchers have begun to investigate whether alterations in brain connectivity occur in patients with immune-related skin diseases, thereby exploring the connectome perspective in understanding the pathogenesis of these diseases. This review aims to synthesize and analyze recent neuroimaging studies about immune-related skin diseases, including systemic lupus erythematosus, psoriasis, chronic spontaneous urticaria, and atopic dermatitis. We mainly discussed the connectome studies related to these diseases and summarized the underlying mechanisms associated with their clinical manifestations, progression, and treatment. Then from our perspectives, we believe that interdisciplinary collaborations encompassing fields such as neurology, psychiatry, dermatology, and neuroimaging will be instrumental in advancing our understanding of immune-related skin diseases. Furthermore, multi-omics approaches will enable a comprehensive exploration of the molecular mechanisms underlying these neural changes, facilitating the identification of novel diagnostic biomarkers and therapeutic targets.

Mental Health Interventions in Refractory Chronic Spontaneous Urticaria: A Call to Expand Treatment Guidelines

Chronic spontaneous urticaria (CSU) is a complex inflammatory skin condition that severely impacts patients' quality of life. For some patients, conventional treatments, including second-generation antihistamines, omalizumab, and cyclosporine A, fail to achieve sustained control. Emerging evidence suggests that psychiatric comorbidities, such as generalized anxiety disorder (GAD), exacerbate CSU through neuro-immuno-cutaneous (the interaction between the nervous system, immune system, and skin) mechanisms. We present the case of a 35-year-old female with refractory CSU and GAD. Despite escalating doses of omalizumab and the addition of cyclosporine A, disease control remained unstable. The introduction of cognitive behavioral therapy (CBT) and escitalopram resulted in significant improvement, achieving complete resolution of symptoms within eight weeks. Following discontinuation of both escitalopram and omalizumab, urticaria relapsed after a stressful event and during pregnancy. The reintroduction of escitalopram and CBT reestablished full control of urticaria. The patient continues on escitalopram and CBT without needing additional pharmacological intervention for CSU. This case underscores the importance of incorporating mental health interventions in managing refractory CSU, as psychiatric comorbidities may exacerbate CSU by intensifying neuro-immune interactions, particularly during stressful periods. Integrating mental health care into treatment guidelines can offer significant benefits, improving symptom control, reducing the need for aggressive pharmacotherapy, and enhancing patients' quality of life.

Assessing Preferences of Patients with Chronic Spontaneous Urticaria for Injectable Treatment Profiles

BACKGROUND

In the context of injectable biologic products approved or in development for chronic spontaneous urticaria (CSU), it is important to capture which treatment attributes matter most to patient and what trade-offs patients are willing to make.

OBJECTIVES

The CHOICE-CSU study aimed to quantify patient preferences toward injectable treatment attributes among patients with CSU, inadequately controlled by H1-antihistamines.

METHODS

This was a two-phase cross-sectional patient preference study in adult patients with a diagnosis of CSU, inadequately controlled by H1-antihistamines. A qualitative phase collected patients' insights and relevant treatment attributes that mattered to them, and the outputs were used for the quantitative phase to create the actual injectable treatment profiles with attributes and levels such as: efficacy, safety, and mode of administration. The quantitative phase used discrete choice experiment (DCE) methodology. Eligible patients were asked to make hypothetical choices between 12 treatment profile pairs, created by Sawtooth SoftwareTM. The DCE data were analyzed using hierarchical Bayesian logistic regression models, enabling the quantification of the relative importance of each attribute/level during the decision-making process.

RESULTS

A total of 450 respondents participated in the DCE. The key attributes driving respondent preference amongst injectable treatment options were type of administration device (relative importance 18.5%), complete control of urticaria (relative importance 17.4%), and resolution of angioedema (relative importance 16.4%). Keeping all other attributes and levels equal, the predicted choice share was higher for a profile with an auto-injector versus one with a pre-filled syringe (72.9% versus 27.1%).

CONCLUSIONS

The CHOICE-CSU study is the first study to provide a quantitative assessment of preferences that patients with CSU, inadequately controlled by H1-antihistamines, have for injectable treatment attributes. Symptom-free periods are the most important overriding therapy goal for patients, and patients will accept some inconveniences, such as administration mode, to achieve this. Additionally, when efficacy is equivalent, administration ease of injectable therapies is valued by patients. As new CSU oral treatment options emerge, additional testing of patient preference toward oral treatments will be required.

Validity, reliability and responsiveness of digital visual analogue scales for chronic spontaneous urticaria monitoring: A CRUSE® mobile health study

BACKGROUND

CRUSE® is an app that allows patients with chronic spontaneous urticaria (CSU) to monitor their daily disease activity through the use of visual analogue scales (VASs). We aimed to determine the concurrent validity, reliability, responsiveness and minimal important difference (MID) of CRUSE® VASs.

METHODS

We evaluated the properties of three daily VASs: VAS for how much patients were affected by their CSU ('VAS urticaria'), VAS for the impact of urticaria on work/school productivity ('VAS productivity') and the VAS of EQ-5D. Concurrent validity was assessed by measuring the association between each VAS and the Urticaria Activity Score (UAS). Intra-rater reliability was determined based on the data of users providing multiple daily questionnaires within the same day. Test-retest reliability and responsiveness (ability to change), respectively, were tested in clinically stable and clinically unstable users. MIDs were determined using distribution-based methods.

RESULTS

We included 5938 patients (67,380 days). Concurrent validity was high, with VAS urticaria being more strongly associated with the UAS score than the remaining VASs. Intra-rater reliability was also high, with intraclass correlation coefficients (ICC) being above 0.950 for all VASs. Moderate-high test-retest reliability and responsiveness were observed, with reliability ICC being highest for VAS EQ-5D and responsiveness being highest for VAS urticaria. The MID for VAS urticaria was 17 (out of 100) units, compared to 15 units for VAS productivity and 11 units for VAS EQ-5D.

CONCLUSION

Daily VASs for CSU available in the CRUSE® app display high concurrent validity and intra-rater reliability and moderate-high test-retest reliability and responsiveness.

Urticaria Voices: Real-World Experience of Patients Living with Chronic Spontaneous Urticaria

INTRODUCTION

The impact of chronic spontaneous urticaria (CSU) on patients' health-related quality of life (HRQoL) is well documented. However, considerable gaps remain in understanding the experience, perception and needs of patients with CSU. In this study, we investigate the perspective of patients with CSU about the disease journey, treatment and management of the condition as well as the physical and psychosocial impact of the disease.

METHODS

A multinational, cross-sectional online survey was completed by patients with chronic urticaria (CU) and physicians treating CU. This analysis focuses on data from the patients with CSU. The patient survey included customized questions and a validated patient-reported outcomes measure, the Urticaria Control Test (UCT).

RESULTS

A total of 582 patients with CSU (62% women; mean [standard deviation, SD] age: 42.2 [11.9] years) completed the online survey. Patients reported a mean (SD) diagnostic delay of 2 (5.4) years and saw 6.1 (8.9) physicians. The majority (79%) of patients were on antihistamines, of which 84% were inadequately controlled (UCT score of < 12) and reported a significantly higher negative impact of CSU on the HRQoL domains than adequately controlled patients, with the highest impact on mental and emotional well-being and social life and intimate relationships. More than half (55%) of the patients experienced angioedema with a mean (SD) of 7.7 (14.0) episodes per year. In addition, sleeping problems (62%), pain (55%) and fatigue (49%) were frequently reported physical symptoms during an exacerbation.

CONCLUSION

Patients with CSU experience substantial burden due to delayed diagnosis, insufficient symptom control (despite treatment) as well as mental and emotional well-being and social impact, particularly when uncontrolled. Early diagnosis and patient-centered approaches to symptom management and disease control should be prioritized to minimize the negative impact of CSU on patients' life.

Urticaria and other mimickers of urticaria

Urticaria is a mast cell-dependent skin disease characterized by the presence of hives, angioedema, or both in the absence of systemic symptoms. It may be acute, or chronic. (1) Acute urticaria (AU) is common in children, affecting boys and girls equally. Chronic urticaria (CU) affects adult women more (3). AU affects more than 20% of the population and CU 0.1 and 1.5%. There are many pathologies that do not meet the clinical criteria for urticaria, despite being called urticarias, which leads to erroneous diagnoses and inconclusive epidemiology. This review attempts to clarify when we should consider urticaria as such and what are the diagnoses that can be considered urticaria without being so.

Prevalence and Burden of Chronic Spontaneous Urticaria in Japan: A Cross-Sectional Study

Background: Real-world data on the prevalence and burden of patients with chronic spontaneous urticaria (CSU) are limited in Japan. This study aimed to estimate CSU prevalence and assess its humanistic and economic burden. Methods: This analysis utilized data from Japanese adult respondents self-reporting physician-diagnosed CSU collected through the 2019 National Health and Wellness Survey. The weighted 12-month prevalence was estimated using 2018 international census projections. Outcomes included the SF-12v2 (physical and mental component summary [PCS and MCS] scores), health utility index (SF-6D and EQ-5D), Dermatology Life Quality Index (DLQI), Generalized Anxiety Disorder-7, Patient Health Questionnaire-9, Work Productivity and Activity Impairment scores at data collection, and healthcare resource utilization over the past 6 months. Results: Among 30,006 respondents, 334 reported having CSU, of whom 62.3% were female. The mean (SD) age at data collection and CSU diagnosis was 50.8 (15.3) and 39.2 (14.9) years, respectively. The weighted prevalence of CSU was 1.1%. The mean (SD) PCS and MCS scores were 50.3 (7.0) and 45.1 (10.0), respectively. The mean (SD) health utility measures (SF-6D and EQ-5D) were 0.71 (0.13) and 0.79 (0.18), respectively. The mean (SD) DLQI score was 3.8 (6.0). More than 40% of patients reported mild/moderate/severe anxiety and depression. The mean % (SD) scores for absenteeism, presenteeism, overall work impairment, and activity impairment were 7.6 (17.6), 27.2 (27.2), 30.3 (29.6), and 28.5 (27.8), respectively. Approximately 90.0% of patients visited healthcare providers, including emergency room visits (6.9%) and hospitalizations (9.9%). Conclusions: This study provides insights into the diagnosed prevalence and burden of CSU in Japan, highlighting its impact on patients' lives.

Sexual Functions are Impaired in Males and Females with Chronic Spontaneous and Inducible Urticaria; A Controlled Study

INTRODUCTION

Sexual dysfunction (SD) related to chronic dermatological diseases in females and males have been reported in the literature, but there are few reports on the effects of chronic urticaria (CU) on male and female sexual function.

OBJECTIVES

The aim was to investigate the prevalence of SD in females and erectile dysfunction (ED) caused by two different CU subtypes.

METHODS

Our study included 100 patients with CU (60 chronic spontaneous urticaria ([CSU]) and 40 chronic inducible urticaria [CIndU]) and 60 healthy controls. The Urticaria Activity Score 7, Urticaria Control Test, Dermatology Life Quality Index, Beck Depression Inventory, International Index of Erectile Function (IIEF), and Female Sexual Function Index (FSFI) were assessed in patients and controls.

RESULTS

Patients with CSU and CIndU had a higher prevalence of female SD (83% and 70%, respectively, vs 20%; P <0.001) and ED (43% and 50%, respectively vs 10%; P <0.05, for all) than controls. CSU and CIndU patients both had lower FSFI scores than controls (median 23.35 and 23.9, respectively, vs controls 30.75; P <0.001). Overall score of IIEF was lower in the CSU group than in the control group (median 60 vs 67; P = 0.005). Depressive symptoms both in males and females with CU was associated with more impairment in sexual functions (r=-0.44, r=-0.47; P <0.001).

CONCLUSIONS

Sexual function is affected in both female and male patients with CSU and CIndU. Given that sexual health is a crucial aspect of QoL, it should be considered when assessing treatment outcomes and disease control.

Cost-of-illness analysis of chronic urticaria clinical management in five countries of Latin America

INTRODUCTION

Chronic spontaneous urticaria (CSU) is a disease with a high impact on the quality of life of patients. There are some evaluations of the economic cost of the disease in developed countries, but there is little information about the economic cost of the disease in developing countries. Our aim was to assess the economic diagnostic and therapeutic expenses of CSU in five Latin American (LA) countries.

METHODS

A noninterventional multicenter cross-sectional study was conducted in five LA countries: Brazil, Colombia, Ecuador, Mexico, and Peru. To determine the frequency of medical interventions as well as clinical and sociodemographic characteristics of CSU patients, questionnaires were administered to patients, primary care physicians, allergists, and dermatologists. In each country, diagnostics and therapeutic expenses were calculated by reviewing medical records, health insurance, and interviews. The main outcome was the yearly economic burden from the healthcare insurance perspective in each country.

RESULTS

According to the projected costs, Brazil had the highest urticaria cost per patient/year (7009.4 USD), followed by Mexico (3695.1 USD), Ecuador (3132.8 USD), Peru (2693.9 USD), and Colombia (2392.8 USD); the cost and the frequency of use of omalizumab and antihistamines explain the total cost differences between countries. Interventions such as medical visits and exams had similar costs between countries and represented less than 10% of total urticaria cost analysis in the five countries.

CONCLUSION

The cost of the CSU in LA varies widely based on the health insurance coverage, the cost of the therapies, and the frequency of therapies used. Strengthening national health systems, as well as following the recommendations of international guidelines, seems to reduce the cost of CSU and improve the quality of patients.

Disease control and quality of life in chronic spontaneous urticaria and recurrent angioedema are strongly linked, but not in all patients

BACKGROUND

Patient-reported outcome measures (PROMs) help to assess disease control and quality of life (QoL) in chronic spontaneous urticaria (CSU) and recurrent angioedema (RA). This study aimed to assess the correlation between two different concepts: disease control and QoL, using disease-specific PROMs.

METHODS

We analyzed data from 445 CSU and 330 RA patients who completed both a disease control and QoL PROM as part of the clinical routine. We included the UCT and CU-Q2oL for CSU and AECT and AE-QoL for RA.

RESULTS

In CSU and RA, disease control scores positively correlated with QoL scores (Spearman's rho correlation coefficient (CR) -0.757, -0.735; p < 0.001) with better disease control corresponding to better quality of life. However, 5.9% of CSU patients and 28% of RA patients with complete disease control had impaired QoL. In CSU, QoL was impaired in 69.2% of patients based on the CU-Q2oL and in 62.7% of patients based on a single numeric question from the UCT, with a mismatch in 89/445 patients. In RA, QoL was impaired in 58.5% using the AE-QoL and in 52.7% using a single numeric question from the AECT30mo, with a mismatch in 69/330 patients. Different domains of the QoL PROMs showed different degrees of influence on disease control, with "Itching/Embarrassment" showing the strongest correlation with the UCT (CR -0.804; p < 0.001) and "Functioning" with the AECT3mo (CR -0.824; p < 0.001).

CONCLUSION

Although most patients with controlled disease have better quality of life, unexpectedly, quality of life remains impaired in up to one-fourth of patients with completely controlled CSU and RA. Reasons behind this should be investigated in further studies.

Sexual Dysfunction in Chronic Urticaria: A Systematic Review

INTRODUCTION

Chronic urticaria (CU) is frequently a debilitating skin condition characterized by recurrent and spontaneous wheal and flares with significant impact on quality of life. This systematic review examines the impact of CU on sexual health.

METHODS

A systematic review using PubMed, Embase, Web of Science, and Cochrane library databases was conducted for articles on sexual health in chronic urticaria.

RESULTS

The database search produced 741 articles, of which 14 articles met inclusion criteria. Study design, patient demographics, disease characteristics, measures used to assess sexuality or sexual function, and study results were independently extracted for each article by two researchers. Any discrepancies were resolved to consensus by a third reviewer. Sexual dysfunction was common in patients with CU and its severity is associated with increased disease activity and poor disease control.

CONCLUSION

Sexual dysfunction is common in patients with CU, and it negatively affects their quality of life (QoL), body image, sleep quality, and mental health. Incorporating sexual health assessments into CU trials will allow for valuable insights into efficacy of study medications on this important QoL domain. Increased awareness of sexual impairment in CU is needed to provide comprehensive care.

Gut microbial alteration in chronic spontaneous urticaria unresponsive to second generation antihistamines and its correlation with disease characteristics- a cross-sectional case-control study

BACKGROUND

Gut microbial involvement has been speculated in chronic spontaneous urticaria (CSU). The aim of the study was to compare the gut microbiome composition and diversity in CSU patients uncontrolled with second-generation antihistamines (sgAHs) and healthy individuals, as well as to explore any association between gut microbiome and disease characteristics.

METHODS

A cross-sectional case-control study including 20 CSU patients unresponsive to standard doses of sgAHs, and 15 age-and-sex matched healthy controls was conducted. Clinico-demographic profile, laboratory investigations and stool analysis were conducted in all study participants. 16S RNA gene sequencing and DNA isolation was performed for all stool samples, followed by bioinformatic analysis.

RESULTS

The CSU patients (mean age 39.5 ± 9.3, M:F 1:4) and healthy controls (mean age 35 ± 13, M:F 1:2) were statistically comparable. The median (IQR) duration of CSU was 42 months (7-81). Concomitant angioedema and concomitant symptomatic dermographism were present in 30% and 20% CSU patients, respectively. At inclusion, 60% patients were receiving add-on omalizumab, while the remaining 40% were on up-dosed sgAHs. Stool microbial analysis revealed increased diversity and higher microbial richness in CSU patients compared with healthy individuals. CSU patients showed reduced load of short-chain fatty acid (SCFA) producing microbiota and increased load of opportunistic pathogens. The Firmicutes/Bacteroides (F/B) ratio was higher in CSU patients. Among CSU patients, higher Bacteroides and reduced Firmicutes count were associated with higher disease activity and poor control; however, there was no link with the type of therapy.

CONCLUSION

Gut microbial dysbiosis is seen in CSU and is linked with disease control.

Urticaria

Urticaria (hives) is a common disorder that may be associated with angioedema (swelling that occurs beneath the skin). It is generally classified as acute or chronic, and chronic urticaria is further classified as spontaneous or inducible Second-generation, non-sedating histamine type 1 (H1)-receptor antihistamines represent the mainstay of therapy for both acute and chronic urticaria. Second-line treatment for uncontrolled chronic urticaria includes omalizumab (a monoclonal anti-immunoglobulin E [IgE] antibody). In this article, we review the causes, diagnosis and management of urticaria (with or without angioedema).

Distinct IgE sensitization profiles in chronic urticaria: a comparative study with classic allergic diseases

Introduction

Chronic urticaria (CU) is not traditionally classified as an allergic disease, but emerging evidence suggests a link to atopy. The quintessential marker of atopy is IgE sensitization, there is scarce information on the IgE sensitization characteristics of CU.

Methods

To investigate IgE sensitization characteristics in CU, and compare them with classic allergic diseases. We retrospectively analyzed the results of specific IgE (sIgE) and total IgE (tIgE) in CU patients, explored the distribution patterns of these atopic markers in CU, and compared these data with those of atopic dermatitis (AD), allergic rhinitis (AR), asthma (AS), and healthy controls (HC).

Results

1149 patients (396 CU, 411 AD, 101 AR, 139 AS and 102 HC) were included in the study. 33.1% of CU patients showed positive sIgE and 49.0 % had elevated tIgE levels, significantly higher than those in HC. Comparative analysis with classic allergic diseases showed CU patients had a lower sIgE positivity rate but no significant difference in tIgE levels. Gender and age influenced sensitization profiles, with male CU patients showing a higher sIgE positivity rate. The distribution of sIgE levels, allergen categories, and tIgE elevated levels range in CU differed from classic allergic disease. The concordance rate between sIgE and tIgE results in CU was lower than in classic allergic disease.

Conclusion

Our study reveals that a significant proportion of CU patients display IgE sensitization, suggesting a clear atopic background compared to the general population. However, the IgE sensitization profile in CU differs from that of classical allergic diseases such as AD, AR, and AS, characterized by relatively lower intensity of IgE sensitization. The underlying reasons for this phenomenon and its clinical implications in CU warrant further research.

Phototherapy as an alternative in the treatment of chronic spontaneous urticaria

Chronic spontaneous urticaria (CSU) is defined as the occurrence of hives, angioedema, or both, lasting for more than 6 weeks. The treatment is based on the use of antihistamines, omalizumab, and/or cyclosporine following a stepwise algorithm recommended by international guidelines with a high level of evidence. Nevertheless, management can be challenging as some patients do not respond to the suggested drugs or have difficulties accessing them for various reasons. In such cases, phototherapy has been reported as a potential treatment option. The evidence on the effectiveness of phototherapy is limited. Most studies have methodological limitations and involve small numbers of patients. A systematic review and meta-analysis of four studies in 2020 concluded that, despite the limited number of randomized controlled trials and the low level of evidence, considering overall efficacy, risk/benefit balance, and costs, narrow band ultraviolet B therapy (NB-UVB) may be a useful adjunct therapy for CSU. Other studies have suggested that the effectiveness of combined antihistamine and phototherapy appears to be more effective than antihistamine alone, although this is based on very low-quality evidence. Additionally, the risk of recurrence was lower with the combination therapy. The objective of this review was to evaluate the role of phototherapy in the treatment of CSU. While randomized studies with a larger number of participants providing a high level of evidence are still needed, we consider phototherapy to be a valuable tool in specific clinical contexts, such as a bridge to the initiation of other medications or until spontaneous remission of the condition occurs.

Association between immune cells and urticaria: a bidirectional Mendelian randomization study

Urticaria is characterized by transient itchy symptoms on the skin, usually accompanied by swelling, which is caused by mast cell activation leading to increased vascular permeability and dilation of the dermis. Urticaria involves recurrent activation of mast cells, T cells, eosinophils, and other immune cells around lesioned venules, with complex regulatory systems affecting mast cell functions, potentially contributing to urticaria pathogenesis. The direct causal relationship between immune cells and urticaria is currently unclear. To address this, our study utilized a bidirectional Mendelian randomization analysis, employing instrumental variables (IVs) associated with immune cells and urticaria, to investigate this causal relationship. First, by utilizing Genome-wide Association Study (GWAS) data, we identified 31 immunophenotypes associated with urticaria risk, with 18 increasing and 13 decreasing the risk. Through rigorous criteria, we identified 4 immunophenotypes that have a strong causal relationship with urticaria. Notably, HLA DR+ CD4+AC, CD45 on CD8br, and HLA DR on plasmacytoid dendritic cells were associated with an increased risk, while CD8dim NKT %lymphocyte was identified as a protective factor. Sensitivity analyses, including the MR-Egger intercept test, scatter plots, funnel plots, and leave-one-out analysis, supported the robustness of the findings. Reverse MR analysis suggested an inverse causal effect of urticaria on CD8dim NKT %lymphocyte, reinforcing the potential bidirectional nature of the relationship between urticaria and immune cell phenotypes. Our research substantiates the bidirectional causal relationship between immune cells and urticaria, thus benefiting for urticaria-targeted therapy development.

Validation and correlations of the Angioedema Activity Score (AAS), Angioedema Quality of Life (AE-QoL) questionnaire, and Angioedema Control Test (AECT) in Chinese patients with angioedema

Background

The impact of recurrent angioedema can be severely debilitating and remains difficult to quantify. Several standardized patient-reported outcome measures (PROMs), including the Angioedema Activity Score (AAS), Angioedema Quality of Life (AE-QoL) questionnaire, and Angioedema Control Test (AECT), have been developed and translated into different languages. However, these PROMs have yet to be validated in Chinese individuals, and their correlations in the Chinese population remain unknown.

Objective

Our aim was to validate the Chinese versions of the AAS, AE-QoL questionnaire, and AECT and assess their intercorrelations.

Methods

A prospective cohort of 118 Chinese patients with recurrent angioedema at the Angioedema and Urticaria Centre of Reference and Excellence in Hong Kong completed the traditional Chinese versions of the AAS, AE-QoL questionnaire, and AECT. We analyzed the reliability and validity of these PROMs and their correlations with each other as well as with generic PROMs.

Results

The Chinese AAS, AE-QoL questionnaire, and AECT demonstrated excellent internal consistency (Cronbach α = 0.920, 0.976, and 0.832, respectively; McDonald ω = 0.972, 0.977, and 0.901, respectively). Confirmatory factor analysis for the AE-QoL questionnaire showed an acceptable fit with the 4-dimensional model (comparative fit index = 0.869; Tucker-Lewis index = 0.842). The AECT showed significant correlations with both the AAS and AE-QoL questionnaire (ρ = -0.750 and -0.456 respectively [both P < .05]). The AE-QoL questionnaire was moderately correlated with certain domains of generic PROMs such as the Work Productivity and Activity Impairment Questionnaire: General Health, version 2.0, and the Short Form 12-Item Health Survey, version 2 (all ρ < 0.60).

Conclusion

The Chinese AE-QoL questionnaire, AAS, and AECT are valid and reliable tools for use with Chinese patients. More validated tools should be made available to improve patient care and research for all patients with angioedema globally.

Prioritising patient-centred care in the management of chronic urticaria in Asia-Pacific countries

Background

Chronic urticaria (CU), in both inducible and spontaneous forms, is associated with a substantial burden in the Asia-Pacific region (APAC). Patient-centred care recognises patients desire to be involved in decisions regarding their health. Although patient-centred approaches have previously not been studied in the context of CU management, they have demonstrated benefits in the management of other chronic conditions.

Methods

Information and opinions regarding the barriers and solutions to the implementation of patient-centred approaches to the management of CU were gathered from a group of 13 expert dermatologists and allergist/immunologists from APAC through surveys and a face-to-face meeting.

Results

Barriers identified there included a lack of awareness of CU amongst patients, delays in consulting healthcare providers, financial constraints, and low adherence. Particular issues raised included a lack of suitable online information for patients (83% of experts), and patients accessing oral corticosteroids without a prescription. Compliance issues were also identified as key reasons for inadequate responses to treatments (67% of experts). Solutions proposed by the authors were improving patients' knowledge about their condition (92% strongly agree, 8% agree), physicians' consideration of patient characteristics when choosing treatments (92% strongly agree, 8% agree), implementing shared decision-making (85% strongly agree, 15% agree), and using patient-reported outcome measures (70% strongly agree, 23% agree).

Conclusion

Expert opinion within APAC supports the use of patient-centred approaches to improve the management of CU. We provide several recommendations focusing on patient education and involvement in disease management as well as disease monitoring methods that can be implemented by physicians in APAC.

Leukotriene receptor antagonists as add-on therapy to antihistamines for urticaria: Systematic review and meta-analysis of randomized clinical trials

BACKGROUND

The benefits and harms of adding antileukotrienes to H1 antihistamines (AHs) for the management of urticaria (hives, itch, and/or angioedema) remain unclear.

OBJECTIVE

We sought to systematically synthesize the treatment outcomes of antileukotrienes in combination with AHs versus AHs alone for acute and chronic urticaria.

METHODS

As part of updating American Academy of Allergy, Asthma & Immunology and American College of Allergy, Asthma, and Immunology Joint Task Force on Practice Parameters urticaria guidelines, we searched Medline, Embase, Central, LILACS, WPRIM, IBECS, ICTRP, CBM, CNKI, VIP, Wanfang, US Food and Drug Administration, and European Medicines Agency databases from inception to December 18, 2023, for randomized controlled trials (RCTs) evaluating antileukotrienes and AHs versus AHs alone in patients with urticaria. Paired reviewers independently screened citations, extracted data, and assessed risk of bias. Random effects models pooled effect estimates for urticaria activity, itch, wheal, sleep, quality of life, and harms. The GRADE approach informed certainty of evidence ratings. The study was registered at the Open Science Framework (osf.io/h2bfx/).

RESULTS

Thirty-four RCTs enrolled 3324 children and adults. Compared to AHs alone, the combination of a leukotriene receptor antagonist with AHs probably modestly reduces urticaria activity (mean difference, -5.04; 95% confidence interval, -6.36 to -3.71; 7-day urticaria activity score) with moderate certainty. We made similar findings for itch and wheal severity as well as quality of life. Adverse events were probably not different between groups (moderate certainty); however, no RCT reported on neuropsychiatric adverse events.

CONCLUSION

Among patients with urticaria, adding leukotriene receptor antagonists to AHs probably modestly improves urticaria activity with little to no increase in overall adverse events. The added risk of neuropsychiatric adverse events in this population with leukotriene receptor antagonists is small and uncertain.

Omalizumab for the Treatment of Chronic Spontaneous Urticaria in Adults and Adolescents: An Eight-Year Real-Life Experience

Background: Omalizumab, an anti-IgE monoclonal antibody, is an effective treatment for patients with chronic spontaneous urticaria (CSU) resistant to antihistamines, but about 10% are unresponsive. Our aim was to assess the effectiveness, safety, and drug survival (DS) of omalizumab by considering clinical and laboratory characteristics. Methods: We conducted a retrospective study on 296 patients with severe CSU treated with omalizumab. Disease activity, comorbidities, and serum levels of total IgE and anti-thyroid autoantibodies were evaluated over a period of up to 8 years. DS was analyzed using unadjusted Kaplan-Meier survival curves. When applicable, the risk of discontinuation was assessed using Cox regression analysis. Results: Out of 296 patients, 118 (40.4%) were early responders, 72 (25.0%) were late responders, 76 (26.0%) were partial responders, and 25 (8.6%) were non-responders. Early responders were more likely to be patients without associated inducible urticaria (p = 0.021, χ2 = 9.692), without autoimmune thyroiditis (p = 0.007, χ2 = 12.037), and those with higher IgE levels (p = 0.039, χ2 = 8.385). Overall, DS was 53.5% at 8 years, primarily due to clinical remission. DS due to inefficacy and clinical remission were 83.9% and 62.1%, respectively, at 8 years. No patients discontinued omalizumab due to adverse events. Patients with normal IgE levels (p = 0.012, HR = 4.639, CI: 1.393-15.445) and those with autoimmune thyroiditis (p = 0.028, HR = 3.316, CI: 1.128-8.718) had a higher risk of discontinuing omalizumab due to inefficacy. Conclusions: This study confirms the long-term effectiveness and safety of omalizumab in the treatment of CSU over a period of up to 8 years. Most patients discontinued omalizumab due to clinical remission, while only 5.1% discontinued it due to ineffectiveness.

Characterization of omalizumab updosing patterns and predictive factors in chronic spontaneous urticaria: A prospective multicentric observational study

BACKGROUND

Limited information is available on the use of omalizumab (OMA) updosing since its introduction as a second-line therapy in chronic spontaneous urticaria (CSU) in 2014. Practical guidelines from health authorities are lacking, and the specific characteristics of patients requiring higher doses remain unknown. Our objectives were to characterize the patterns of OMA updosing (defined as changes in dose and/or injection intervals), to identify the predictive factors associated with updosing, and to improve CSU management.

METHODS

We conducted a prospective, multicentric, real-life observational study, including patients diagnosed with CSU and starting OMA. The data were collected at 0, 3, 6, and 9 months. The primary endpoint was the frequency of OMA updosing at 3 months. The secondary endpoints included an analysis of updosed patients' profile, and an assessment of OMA efficacy and safety.

RESULTS

We included 153 patients. Twenty percent of patients were updosed at 3 months, and 27% in total during the 9-month follow-up. Practitioners mainly chose to increase the frequency of injections (66%). At baseline, the updosed patients were more likely to have more severe CSU (UCT < 4, p < 0.030), a lower lymphocyte count (<2000/mm3, p = 0.037), and low IgE levels (<70 UI/mL, p = 0.024). The side effects of OMA were not more frequent after updosing.

CONCLUSION

One in five patient underwent updosing within just 3 months. OMA updosing is frequent in particular in cases of severe disease and low IgE blood levels.

Dupilumab Reduces Urticaria Activity, Itch, and Hives in Patients with Chronic Spontaneous Urticaria Regardless of Baseline Serum Immunoglobulin E Levels

INTRODUCTION

In chronic spontaneous urticaria (CSU), interleukin (IL)-4 and IL-13 may promote mast cell activation directly via IL-4 receptor expression, or indirectly via upregulated immunoglobulin E (IgE) production. Dupilumab significantly improved CSU signs and symptoms in the phase 3, randomized, placebo-controlled LIBERTY-CSU CUPID Study A. This analysis explores the impact of dupilumab on CSU signs and symptoms and serum IgE levels in patients from LIBERTY-CSU CUPID Study A with serum total IgE above and below 100 IU/mL at baseline.

METHODS

Patients with H1-antihistamine-refractory CSU received dupilumab (n = 70) or placebo (n = 68) for 24 weeks. Efficacy endpoints were change from baseline to weeks 12 and 24 in serum total IgE levels, Itch Severity Score over 7 days (ISS7), Urticaria Activity Score over 7 days (UAS7), and Hives Severity Score over 7 days (HSS7) in dupilumab- or placebo-treated patients with serum total IgE above and below 100 IU/mL at baseline.

RESULTS

Dupilumab treatment significantly reduced median (interquartile range) IgE levels at week 12 [dupilumab: -31.9% (-41.9; -22.6); placebo: -6.3% (-21.3; 14.9)] and week 24 [dupilumab: -48.2% (-56.8; - 39.5); placebo: - 6.3% (-34.5; 14.8)]. Similar IgE reductions relative to baseline were observed in dupilumab-treated patients regardless of baseline IgE level. Dupilumab treatment improved ISS7, UAS7, and HSS7 over 12 and 24 weeks, regardless of baseline serum IgE level (interaction p ≥ 0.59 for all treatment by subgroup comparisons), with weak correlations (r < 0.2) observed between IgE level changes and ISS7, UAS7, and HSS7 outcomes.

CONCLUSIONS

Dupilumab significantly improved CSU signs and symptoms and reduced serum IgE, regardless of baseline IgE levels. In the current analysis, baseline total IgE had no predictive value as a dupilumab treatment response biomarker in CSU. Downregulation of IgE, a key mediator of mast cell activation and histamine release, may at least partially explain the effectiveness of dupilumab in reducing CSU signs and symptoms.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04180488.

Exploring the Bidirectional Effects of Gut Microbiota and Short-Chain Fatty Acids on Urticaria Subtypes Through Mendelian Randomization and Mediation Analysis

Background

Emerging evidence links gut microbiota and their by-products, notably short-chain fatty acids (SCFAs), to urticaria. This study employs multiple Mendelian Randomization (MR) analyses to unravel the complex interactions among gut microbiota, SCFAs, and different subtypes of urticaria, aiming to elucidate the underlying mechanisms and enhance future clinical research.

Methods

We analyzed published genome-wide association study (GWAS) summary statistics to identify associations between gut microbiota and three common subtypes of urticaria: spontaneous, dermatographic, and temperature-triggered. Initial two-sample and reverse MR analyses explored the causality in these relationships. Subsequent multivariate MR analyses investigated the role of SCFAs in modulating these interactions, with multiple sensitivity analyses to ensure robustness.

Findings

Specific taxa were differently associated with various urticaria subtypes. From microbiota to urticaria: one taxon was negatively associated with dermatographic urticaria; seven taxa were negatively associated and four positively associated with temperature-triggered urticaria; four taxa were negatively associated and six positively associated with spontaneous urticaria. Conversely, from urticaria to microbiota: five taxa were negatively associated with dermatographic urticaria; four were negatively and two positively associated with temperature-triggered urticaria; and two were negatively associated with spontaneous urticaria. These associations were observed at a nominal significance level (P < 0.05). After applying Bonferroni correction for multiple testing, these associations did not reach statistical significance. The observed trends, however, provide insights into potential microbiota-urticaria interactions. Multivariate MR analyses elucidated the role of SCFAs, particularly acetate, which plays a crucial role in modulating immune response. Adjusting for acetate revealed direct effects of Actinobacteria, Bifidobacteriales, and Bifidobacteriaceae on spontaneous urticaria, with corresponding mediation effects of -22%, -24.9%, and -24.9% respectively. Similarly, adjustments for Alcaligenaceae and Betaproteobacteria indicated significant negative effects of acetate on dermatographic and spontaneous urticaria, with mediation effects of -21.7% and -23.7%, respectively.

Conclusion

This study confirms the interconnected roles of gut microbiota, SCFAs, and urticaria. It highlights SCFAs' potential mediating role in influencing urticaria through microbiota, providing insights for future therapeutic strategies.

Validity, reliability, and sensitivity to change of the traditional Chinese Urticaria Control Test (UCT) in Hong Kong

Background

Uncontrolled chronic urticaria (CU) can severely affect physical and psychosocial health as well as quality of life. Patient-reported outcome measures are crucial for measuring disease control. The Urticaria Control Test (UCT) is recommended by guidelines to monitor CU and guide clinical management. However, the traditional Chinese version of the UCT has not yet been validated.

Objective

We sought to validate the traditional Chinese UCT among Chinese CU patients in Hong Kong.

Methods

Patients with CU were enrolled at a Urticaria Centre of Reference and Excellence (aka UCARE) in Hong Kong and completed the traditional Chinese UCT. The internal consistency, test-retest reliability, construct validity, convergent validity, known-group validity, and sensitivity to change of the traditional Chinese UCT were evaluated.

Results

We recruited 162 CU patients (80.9% female; age 50 ± 14 years) with a mean (median) ± standard deviation baseline UCT score of 8.8 (8) ± 4.7. Overall, Chinese UCT showed excellent internal consistency (Cronbach α and McDonald ω = 0.948), as well as test-retest reliability (intraclass correlation coefficient = 0.916 [95% confidence interval = 0.866-0.953]). Exploratory factor analysis revealed a unidimensional structure and confirmed its construct validity. Strong correlation between UCT and the 7-day urticaria activity score (UAS7) attested to its convergent validity (ρ = -0.699, P < .001). Its known-group validity was supported by significantly different UCT scores among patient subgroups with different disease activity. The Chinese UCT also demonstrated good sensitivity to change, as reflected by the significant correlation between changes in UCT and UAS7 scores (ρ = 0.491, P < .001).

Conclusion

The traditional Chinese UCT is a valid, reliable, and sensitive-to-change instrument among Hong Kong Chinese with CU.

The potential of Bruton's tyrosine kinase (BTK) inhibitors in the pharmacotherapeutic management of immune and dermatological disease

INTRODUCTION

The review article explores the evolving role of Bruton's tyrosine kinase (BTK) inhibitors in immune-mediated dermatological conditions, addressing significant gaps in current treatment approaches.

AREAS COVERED

The review comprehensively discusses the mechanisms of action of BTK inhibitors, including irreversible and reversible inhibitors. Clinical applications of BTK inhibitors in dermatological diseases such as pemphigus, chronic spontaneous urticaria (CSU), hidradenitis suppurativa (HS), systemic lupus erythematosus (SLE), and atopic dermatitis are explored, highlighting recent advancements and ongoing clinical trials. Potential advantages of BTK inhibitors over existing therapies and challenges in translating preclinical findings to clinical outcomes are discussed.

EXPERT OPINION/COMMENTARY

BTK inhibitors represent a promising therapeutic avenue for immune-mediated dermatological conditions, offering oral administration, targeted pathway inhibition, and a favorable safety profile compared to biologic therapies. Ongoing research and clinical trials hold the potential to address unmet needs and reshape the therapeutic landscape in dermatology.

Chronic Inducible Urticaria

Chronic inducible urticaria (CIndU) is characterized by the appearance of hives (urticaria) and/or angioedema in response to specific triggers or stimuli. For accurate diagnosis, anamnesis-driven specific, and if available, standardized trigger testings, as well as patient reported outcomes, should be applied. The currently recommended treatment algorithm is the same as for chronic spontaneous urticaria but is largely off-label for CIndU. New, and possibly more disease-specific, treatment options are needed for CIndU patients, who are often severely impacted by their disease. Several clinical trials are currently ongoing.

Chronic Spontaneous Urticaria: An Update on the Evaluation and Management

Chronic spontaneous urticaria (CSU) affects 0.5% to 1% of the general population and is often managed by allergy and immunology specialists. Guidelines have evolved over the past several decades with an emphasis on decreasing extensive screening laboratory testing as they are of low-yield and cost-ineffective. The utility of biomarkers remains under investigation but total immunoglobulin E may be helpful in determining specific endotypes and response to omalizumab. Antihistamines and omalizumab remain the primary therapeutic options for CSU, but an expanding body of evidence supports the use of immunosuppressants and anti-inflammatory medications in refractory cases.

Chronic Spontaneous Urticaria: Quality of Life and Economic Impacts

This study focuses on quality of life (QoL) assessment in chronic urticaria, delving into tools, disease-specific measures, and its profound impact. With expanding therapeutic options, understanding QoL becomes crucial. QoL measures often involve comparisons of patient-reported outcomes in addition to quantitative measures of disease control. Emerging tools include the Urticaria Activity and Impact Measure, which may provide a balanced evaluation. In addition to discussions of the various QoL measures, the psychological impact of chronic urticaria are highlighted, covering emotional burden, stress, and psychiatric comorbidities. Finally, the economic impacts reveal escalating health care costs and cost-effectiveness considerations of therapies like omalizumab.

The Definition, Classification, and History of Urticaria

The term "urticaria" was first introduced by William Cullen in the eighteenth century. Urticaria is a common mast cell-mediated cutaneous disease presenting with pruritic wheals, angioedema, or both. It is classified as acute (≤6 weeks) or chronic (>6 weeks) and as spontaneous (no definite triggers) or inducible (definite and subtype-specific triggers). The international urticaria guideline on the definition, classification, diagnosis, and management of urticaria is revised every 4 years. The global network of Urticaria Centers of Reference and Excellence, the biggest and most active consortium of urticaria specialists, offers physicians and patients several research, educational, and digital care initiatives.

Emerging Therapeutics in Chronic Urticaria

Chronic urticaria (CU) is a common and long-lasting mast cell-mediated skin disease associated with psychiatric and autoimmune comorbidities, high economic costs, and considerable impact on quality of life. Available therapies show limited efficacy in many CU patients, which may be related to distinct underlying pathophysiology. Targeted and disease-modifying treatments with higher and broader efficacy are needed and are under development for CU. These novel drugs, small molecules, and monoclonal antibodies target mast cells and their receptors, signaling pathways, or mediators and other immune cells. In this article, the authors focus on the most promising emerging therapeutics in advanced development and discuss their potential place in future management of CU.

Evaluation of Guideline Line-Care Approach to the Treatment of Chronic Inducible Urticaria

BACKGROUND

Chronic inducible urticaria (CIndU) management often follows chronic spontaneous urticaria (CSU) guidelines, but a step-by-step evaluation of their effectiveness in CIndU is lacking.

OBJECTIVE

To assess the clinical impact of adapting CSU international guidelines for CIndU management.

METHODS

We conducted a prospective cohort study involving patients diagnosed with CIndU based on challenge tests and a Urticaria Control Test (UCT) score of ≤11 points. Following the guidelines, a stepwise approach was used: avoidance measures, antihistamines, omalizumab, and cyclosporine. Treatment steps were added based on individual response, with control defined as UCT ≥12 points. Pharmacological steps were evaluated for at least 1 month, with the next step initiated in case of a UCT score ≤11 points.

RESULTS

We enrolled 194 patients with CIndU. Of them, 134 patients had CIndU with concomitant CSU and 60 had CIndU only. Following the step-by-step approach outlined in the guidelines, a total of 159 (81.9%) patients reach a UCT ≥12 points, with avoidance measures 23 (11.8%) patients, antihistamines 84 (43.2%), omalizumab 35 (18%), and cyclosporine 17 (8.7%).

CONCLUSIONS

This study supports the use of a stepwise approach based on CSU guidelines for CIndU management. However, a significant proportion of patients, particularly those with CIndU only, did not achieve adequate control. This highlights the heterogeneity within CIndU and the need for further research to develop new therapies for patients with CIndU who remain uncontrolled.

Identification of pyruvic and maleic acid as potential markers for disease activity and prognosis in chronic urticaria

BACKGROUND

Population-based studies have highlighted the link between chronic urticaria (CU) and metabolic syndrome, and metabolic alterations have been revealed in CU. However, to our knowledge, a comprehensive metabolomics study on a large cohort of patients with CU has not been reported.

OBJECTIVE

We sought to explore the underlying metabolic subtypes and novel metabolite biomarkers for CU diagnosis and therapy.

METHODS

Plasma samples from 80 patients with CU and 82 healthy controls were collected for metabolomics quantification and bioinformatics analysis. Another independent cohort consisting of 144 patients with CU was studied to validate the findings. Bone marrow-derived mast cells and mice with IgE-induced passive cutaneous anaphylaxis were used for in vitro and in vivo experiments, respectively.

RESULTS

We observed clear metabolome differences between CU patients and healthy controls. Meanwhile, differential metabolites N6-acetyl-l-lysine, l-aspartate, maleic acid, and pyruvic acid were used to construct random forest classifiers and achieved area under receiver operating characteristic curve values greater than 0.85, suggesting their potential as diagnostic biomarkers of CU. More importantly, by exploring the underlying metabolic subtypes of CU, we found that the low abundance of pyruvic acid and maleic acid was significantly related to the activity of CU, poor efficacy of second-generation H1 antihistamines, and short relapse-free time. The results were validated in the independent cohort. Moreover, supplementation with pyruvate or maleate could significantly attenuate IgE-mediated mast cell activation in vitro and in vivo.

CONCLUSIONS

Plasma pyruvic acid and maleic acid may be effective biomarkers for predicting disease activity, therapeutic efficacy, and prognosis for patients with CU.

Efficacy and Mechanism of Acupoint Catgut Embedding in the Treatment of Chronic Spontaneous Urticaria: Protocol for a Randomized Double-Blind Placebo-Controlled Trial

BACKGROUND

Chronic spontaneous urticaria (CSU) is a common chronic inflammatory skin disease that manifests as itching and wheals, seriously affecting quality of life. Clinical observations and previous research trials have shown that acupuncture is safe and effective for the treatment of CSU. However, there are problems, such as a short duration of action and frequent treatment. Compared with traditional acupuncture, acupoint catgut embedding (ACE) has the advantages of a longer effect and higher compliance. Clinical trials are needed to prove its efficacy and mechanism of action.

OBJECTIVE

This trial aims to provide definitive evidence for the treatment of CSU with ACE and explore the mechanism of ACE.

METHODS

This is a randomized, double-blind, placebo-controlled trial. In this trial, 108 participants aged 18-60 years with a diagnosis of CSU and no history of ACE will be randomly assigned to 2 groups (1:1 ratio) using the Statistical Analysis System: treatment (ACE) and control (sham ACE). The participants and efficacy evaluators will be blinded to the grouping. Both the ACE and sham ACE groups will undergo acupuncture, but the sham ACE group will not receive catgut sutures. Treatment will be performed twice weekly for 8 weeks, with a 1-week run-in period and a 16-week follow-up period. Twenty patients will be randomly selected to undergo functional magnetic resonance imaging before and after the treatment period. The primary outcome will be the urticaria activity score over 7 days (UAS7). We will use R (version 4.0.1; R Project for Statistical Computing) to perform ANOVA and independent samples t tests to compare the differences within and between groups before and after treatment by judging the rejection range based on a significance level of .05.

RESULTS

The study protocol has been approved by the Ethics Committee of Guang'anmen Hospital on September 7, 2022, and has been registered on November 30, 2022. Recruitment began on March 1, 2023. A total of 4-6 participants are expected to be recruited each month. The recruitment is planned to be completed on March 1, 2025, and we expect to publish our results by the winter of 2025. As of November 1, 2023, we have enrolled 25 participants with CSU.

CONCLUSIONS

This randomized, double-blind, placebo-controlled trial aims to provide definitive evidence for the treatment of CSU with ACE and explore the mechanism of ACE. We hypothesize that wheals and itching will show greater improvement in participants receiving active therapy than in those receiving sham treatment. The limitations of this study include its single-center trial design, small sample size, and short treatment duration, which may have certain impacts on the research results.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR2200066274; https://www.chictr.org.cn/showprojEN.html?proj=179056.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/54376.

Assessment of ELR, PLR, NLR and BLR Ratios during Omalizumab Treatment of Chronic Spontaneous Urticaria

Background: There is a need for searching for biomarkers indicating patients who will benefit the most from treatment with omalizumab for chronic spontaneous urticaria (CSU). The aim of this study was to assess whether the eosinophil/neutrophil/platelet/basophil-to-lymphocyte ratio (ELR, NLR, PLR, BLR) may predict the response to omalizumab treatment of chronic spontaneous urticaria. Methods: A retrospective data analysis of CSU patients treated s-c with 300 mg of omalizumab every four weeks under the drug program was carried out. NLR, ELR, PLR and BLR, DLQI, UAS-7, CRP, anti-TPO and tIgE were assessed before (V0) and after three (V3) and six months (V6) of treatment. Results: Among 52 patients with CSU, 21 were responders, 24 were partially responders and 6 were non-responders to treatment with 300 mg omalizumab every four weeks. An amount of 18 patients had features of type I autoallergic CSU (CSUaiTI) and 34 patients had autoimmunity type IIb CSU with mast cell-directed activating autoantibodies (CSUaiTIIb). NLR, ELR, PLR and BLR indices did not change during a six-month-course of biological treatment. Initial values of ELR and BLR were significantly correlated with the initial tIgE level and anti-TPO/IgE ratio. Initial values of NLR, ELR and BLR were significantly correlated with initial CRP. Comparisons between type I autoallergic CSU (CSUaiTI) and autoimmunity type IIb CSU (CSUaiTIIb) revealed that the absolute number and percentage of eosinophils, basophils, BLR and tIgE were significantly higher in type CSUaiTI and anti-TPO and anti-TPO/IgE were significantly lower in type CSUaiTI. Conclusions: NLR, ELR, PLR and BLR do not change significantly during six months of omalizumab treatment and do not appear to be useful in predicting its efficacy.

The relationship between serum transglutaminase-2 levels and the severity of chronic spontaneous urticaria

Chronic spontaneous urticaria (CSU) is an immunological disease that is depicted by high prevalence and eminent burden for patients and society that is attributable to the arbitrary nature of symptoms and inconsistent tools for assessment of activity and severity. Transglutaminase-2 (TG2) is a posttranslational enzyme that is pervasively expressed in many cells and tissue types including mast cells. It has various biological functions, and its role in allergic disorders has been highlighted and delineated through several postulated mechanisms. This case-control study aimed at determining the relationship between serum levels TG2 and severity of CSU. To the best of our knowledge, this is the first study in Egypt to determine the relationship between serum TG2 and severity of CSU. We enrolled 60 adult patients with confirmed diagnosis of CSU. According to urticaria activity score (UAS), patients were categorized into three groups [20 with mild disease; UAS = 0, 20 with moderate disease; UAS = 1-3, 20 with severe disease; UAS = 4-6]. Another 20 healthy individuals (age and gender matched) served as a control group. All patients were subjected to detailed medical history, clinical examination, complete blood count with differential, serum total IgE, CRP, ESR, TSH, ANA, liver and renal function tests. Serum level of TG2 was done by quantitative ELISA for all enrolled patients and controls. Serum TG2 is significantly higher in patients group compared to control group (P value < 0.001). Serum TG2 levels were significantly higher in patients with severe disease compared to patients with moderate or mild disease. This is illustrated by the significant positive correlation between serum TG2 and UAS (r 0.814 and P value 0.000). Moreover, serum TG2 accurately classified CSU patients into mild, moderate and severe subgroups: as regards differentiation between mild and moderate cases (sensitivity 70%, specificity 80%, PPV 77.8, NPV 72.7) and as for the differentiation between moderate and severe cases (sensitivity 95%, specificity 90%, PPV 90.5, NPV 94.7). Serum TG2 may have a pivotal role as a marker of severity in patients with CSU.

Serum Concentration of IL-5 Receptor (IL-5R) and Associations with Disease Severity in Patients with Chronic Spontaneous Urticaria (CSU) and Atopic Dermatitis (AD)

The immunological pathogenesis of atopic dermatitis (AD) and chronic spontaneous urticaria (CSU) has not been fully elucidated yet. The aim of our research was to assess the serum concentration of interleukin-5 receptor (IL-5R) in relation to the disease activity and pruritus intensity in adult patients with AD and CSU. This pilot study included 45 participants (15 patients with AD, 15 patients with CSU, and 15 healthy controls). Blood samples were taken to examine the serum levels of IL-5R using the enzyme-linked immunosorbent assay (ELISA) test. The Scoring Atopic Dermatitis (SCORAD) index, the Urticaria Activity Score (UAS7), and the Visual Analogue Scale (VAS) were used to assess the disease activity and the pruritus intensity, respectively. Obtained results revealed that the IL-5R concentration was significantly higher in patients with CSU than in patients with AD and in the controls (p = 0.038). There was a positive correlation between the IL-5R level and the SCORAD index in patients with AD (r = -0.9, p = 0.047), which was not found for the CSU activity by UAS7 and with the pruritus severity by VAS in both examined groups of patients. Our findings underscore higher serum levels of IL-5R among CSU and AD patients, which may highlight its functional role in the pathogenesis of these diseases. In contrast, IL-5R might not be fully useful in reflecting the severity of symptoms. Although our results are promising, this study should be conducted on a larger cohort of patients.

What can be learned from real-world data about chronic spontaneous urticaria?

Background: Chronic spontaneous urticaria (CSU) is a common disease with complex pathogenesis. Patients' clinical characteristics and responses to treatment vary. Objective: We aimed to investigate the role of data obtained from routinely recommended tests in predicting the response to omalizumab, the only biologic agent approved for treatment, and in defining the clinical characteristics of the patients. Methods: A retrospective study of patients who started omalizumab treatment for CSU between 2015 and 2022 at the Department of Dermatology, Pamukkale University, was conducted. Response criteria were based on the urticaria control test, and patients with a urticaria control test score <12 at 6 months were considered treatment non-responders. Eosinophil and basophil counts, neutrophil-lymphocyte ratio (NLR), systemic immune inflammation index (SII), systemic inflammation response index (SIRI), and total immunoglobulin E (IgE) levels of the patients were evaluated before treatment and at the sixth month of treatment. Results: A total of 23.1% of the patients were unresponsive to omalizumab. The response rate to the omalizumab treatment of the patients with a total IgE level ≤ 30 IU/L (n = 4 [5.7%]) was significantly lower than patients with total IgE level > 30 IU/L (n = 66 [94.3%]) (p = 0.015). The mean ± standard deviation SIRI levels were significantly higher in non-responders versus responders (1.53 ± 1.03 versus 1.15 ± 7.76; p = 0.026). Eosinophil counts positively correlated with basophil counts (r = 587; p < 0.001) and IgE levels (r = 0.290; p = 0.005) but a negative correlation was found with levels of NLR (r = -0.475; p < 0.001), SIRI (r = -0.259; p = 0.013), and SII (r = -0.285; p = 0.006). NLR levels were lower in CSU patients with atopy, than in those without atopy (1.9 ± 0.9 vs 2.9 ± 2.1, p = 0.022). Conclusion: We suggest that eosinopenia and high NLR levels are linked to autoimmune CSU. Predicting a poor response to omalizumab seems possible with total IgE levels < 30 IU/L and high SIRI levels.

Knockdown of miR-155 alleviates skin damage in rats with chronic spontaneous urticaria by modulating the JAK/STAT signaling pathway

OBJECTIVE

The aim of this study was to investigate the role and mechanisms of miR-155 in chronic spontaneous urticaria (CSU).

METHODS

The expression level of miR-155 in the skin tissues of patients with CSU and experimental rats were detected by RT-qPCR, followed by the measurement of the histamine release rate in the serum through the histamine release test. Besides, hematoxylin & eosin staining was used to observe the pathological changes of the skin tissues; Corresponding detection kits and flow cytometry to measure the changes of immunoglobulins, inflammatory cytokines and T cell subsets in the serum of rats in each group; and western blot to check the expression level of proteins related to JAK/STAT signaling pathway in the skin tissues.

RESULTS

Knockdown of miR-155 reduced the number and duration of pruritus, alleviated the skin damage, and decreased the number of eosinophils in CSU rats. Moreover, knockdown of miR-155 elevated the serum levels of IgG and IgM, decreased the levels of IgA and inflammatory cytokines, and reduced the proportion of CD4 + and CD4 + CD25 + T cells, as well as the CD4+/CD8 + ratio in CSU rats. However, Tyr705 intervention could reverse the effects of knockdown of miR-155 on CSU model rats. Furthermore, we found that knockdown of miR-155 significantly reduced the protein expression of IRF-9, as well as the P-JAK2/JAK2 and P-STAT3/STAT3 ratios in the skin tissues of CSU rats.

CONCLUSION

Knockdown of miR-155 can alleviate skin damage and inflammatory responses and relieve autoimmunity in CSU rats by inhibiting the JAK/STAT3 signaling pathway.