Identification of key genes and molecular mechanisms of chronic urticaria based on bioinformatics.

Chronic urticaria (CU) is characterized by persistent skin hives, redness, and itching, enhanced by immune dysregulation and inflammation. Our main objective is identifying key genes and molecular mechanisms of chronic urticaria based on bioinformatics. We used the Gene Expression Omnibus (GEO) database and retrieved two GEO datasets, GSE57178 and GSE72540. The raw data were extracted, pre-processed, and analyzed using the GEO2R tool to identify the differentially expressed genes (DEGs). The samples were divided into two groups: healthy samples and CU samples. We defined cut-off values of log2 fold change ≥1 and p < .05. Analyses were performed in the Kyoto Encyclopaedia of Genes and Genomes (KEGG), the Database for Annotation, Visualization and Integrated Discovery (DAVID), Metascape, Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) and CIBERSOFT databases. We obtained 1613 differentially expressed genes. There were 114 overlapping genes in both datasets, out of which 102 genes were up-regulated while 12 were down-regulated. The biological processes included activation of myeloid leukocytes, response to inflammations, and response to organic substances. Moreover, the KEGG pathways of CU were enriched in the Nuclear Factor-Kappa B (NF-kB) signaling pathway, Tumor Necrosis Factor (TNF) signaling pathway, and Janus kinase/signal transducers and activators of transcription (JAK-STAT) signaling pathway. We identified 27 hub genes that were implicated in the pathogenesis of CU, such as interleukin-6 (IL-6), Prostaglandin-endoperoxide synthase 2 (PTGS2), and intercellular adhesion molecule-1 (ICAM1). The complex interplay between immune responses, inflammatory pathways, cytokine networks, and specific genes enhances CU. Understanding these mechanisms paves the way for potential interventions to mitigate symptoms and improve the quality of life of CU patients.

Increased Neutrophil-Lymphocyte Ratio and Platelet-Lymphocyte Ratio in Chronic and Severe Urticaria.

Chronic spontaneous urticaria (CSU) is a disturbing skin condition often severely detrimental to quality of life. Haematological markers of inflammation such as neutrophil-to-lymphocyte and platelet-to-lymphocyte may be used in the assessment of inflammatory skin diseases. Their usefulness in urticaria is unknown. Neutrophil- to-lymphocyte, platelet-to-lymphocyte, and total serum IgE were investigated in urticaria patients: acute spontaneous urticaria (ASU) versus CSU, children versus adults with CSU, and patients with mild-to-moderate versus severe CSU. This retrospective cohort study included patients of all ages diagnosed with urticaria between 2005 and 2020 and blood counts within 30 days of diagnosis. Patients with comorbidities influencing blood cells (infection, surgery, malignancy) were excluded. Neutrophil-to-lymphocyte and platelet-to-lymphocyte were evaluated in patients with ASU vs CSU and mild-to-moderate CSU vs severe CSU (defined by the use of systemic medications or hospitalizations). A total of 13,541 urticaria patients were included in the study. CSU patients (n = 5,021) had higher neutrophil-to-lymphocyte and platelet-to-lymphocyte, as well as serum IgE levels compared with ASU patients (n = 8,520). Adults had higher neutrophil-to-lymphocyte and platelet-to-lymphocyte than children. Severely affected patients (n = 53) had higher neutrophil-to-lymphocyte and platelet-to-lymphocyte compared with mild-to-moderately affected patients (n = 4,968). Patients with higher neutrophil-to-lymphocyte and platelet-to-lymphocyte had higher odds of having CSU rather than ASU and severe urticaria rather mild-to-moderate. In conclusion, neutrophil-to-lymphocyte and platelet-to-lymphocyte are simple and available markers that can be used to predict and assess severe and chronic urticaria.

Biomarkers to predict therapeutic response in chronic spontaneous urticaria: a review.

Chronic spontaneous urticaria (CSU) is a relatively common dermatological disorder characterized by sudden and unpredictable onset of pruritic wheals and/or angioedema, for more than six weeks. It is a mast cell-mediated histaminergic disorder, considerably worsening patients' quality of life. Current treatment options include anti-histamines, omalizumab and cyclosporine, in a step-wise algorithmic approach, aimed at complete symptom control. Patients do not respond uniformly to these therapeutic options due to phenotypic and endotypic heterogeneity, and often remain uncontrolled/poorly controlled. Recent research is focused on identifying certain biomarkers to predict therapeutic response and facilitate patient-targeted personalized treatment, for maximum benefit. The current article summarizes various biomarkers explored to date, and also elaborates their role in predicting therapeutic response to anti-histamines, omalizumab and cyclosporine, in CSU patients. High disease activity, elevated CRP/ESR and elevated D-dimer are the most important predictors of non/poor-response to antihistamines. Low and very low baseline IgE, elevated CRP/ESR, ASST+, BAT/BHRA+, basopenia, eosinopenia, and elevated D-dimer are predictors of poor and good response to omalizumab and cyclosporine, respectively. Additionally, normal or slightly elevated baseline IgE and FceR1 overexpression are predictors of a faster response with omalizumab. However, none of these predictors have so far been completely validated and are not yet recommended for routine use. Thus, large-scale prospective studies are needed to confirm these predictive biomarkers and identify new ones to achieve the goal of personalized medicine for CSU.

The relationship between sleep quality and chronotype differences and urticaria severity in patients with chronic spontaneous urticaria.

INTRODUCTION: Chronic spontaneous urticaria (CSU) is characterized by persistent or recurrent pruritic lesions that last more than 6 weeks. Patients with CSU may experience sleep disturbances, particularly due to itching. Biological rhythms (chronotypes) are categorized as morningness, intermediate, and eveningness types. This study evaluates the relationship between sleep quality, chronotype, and disease severity in CSU patients. METHODS: The study included 53 CSU patients and 50 healthy controls. A sociodemographic data form was completed, and the disease severity was determined utilizing the Urticaria Activity Score over 7 days (UAS7). The Hospital Anxiety and Depression Scale (HADS), Insomnia Severity Index (ISI), and Pittsburgh Sleep Quality Index (PSQI) scales as well as the Morningness-Eveningness Scale (MEQ) were applied to the participants. RESULTS: The CSU group had a significantly higher body mass index (BMI) than that of the healthy control group. In terms of sleep and chronotype scales, compared to the control group, the CSU group had higher ISI scores as well as subscale scores on the PSQI subscales, with the exception of habitual sleep efficiency and total PSQI scores. There was no difference between MEQ scores. In the correlation analysis, the UAS7 and PSQI total scores were found to be correlated, whereas in the logistic regression analysis the estimated relative risk of BMI and PSQI total score for CSU was found to be 1.13 and 1.45, respectively. CONCLUSIONS: When dealing with CSU patients, it is necessary to conduct a sleep quality assessment as part of a holistic evaluation.

Efficacy and safety of Xiaofeng powder in the treatment of chronic urticaria: A systematic review and meta-analysis.

BACKGROUND: Chronic urticaria is a group of skin diseases characterized by pruritus and/or vascular oedema and belongs to the category of "addictive rash" in Traditional Chinese Medicine, and its aetiology is closely related to wind evil. Antihistamines are often used in treatment. Although they have certain effects, they also easily cause disease recurrence. Xiaofeng powder treats this disease has a significant effect in improving the disease state and reducing the recurrence rate. However, there is a lack of evidencebased research. This study to systematically evaluate the clinical efficacy of modified Xiaofeng powder in the treatment of chronic urticaria (CU). METHODS: Computer searches of Chinese databases such as China National Knowledge Infrastructure, China Scientific Journal Database, China Biomedical Literature Database, and WanFang Date and foreign databases such as PubMed and the Web of Science were performed. We retrieved published clinical randomized controlled trials of Xiaofeng powder in the treatment of CU from the establishment of the databases to November 2023. The data were extracted from clinical trials that met the inclusion criteria of this study, and the quality was evaluated through the Cochrane Handbook of Systematic Reviews 5.1.0. Finally, a meta-analysis was performed using RevMan 5.3 statistical software. RESULTS: A total of 11 randomized controlled trials involving 1076 patients were included. The cure rate odds ratio (OR) and 95% confidence interval (CI; shown in brackets) were 2.11 [1.45, 3.07]; the total effective rate OR and CI were 2.42 [1.60, 3.68]; the recurrence rate OR and CI were 0.22 [0.15, 0.34]; the adverse reaction rate OR and CI were 0.23 [0.12, 0.45]; and the mean weighted mean difference (MD) and 95% CI (shown in brackets) of itching degree, wind mass size, wind mass number and wind mass duration in symptom and sign integrals were -0.70 [-0.73, 0.67], -0.64 [-0.96, 0.31], , -0.72 [-1.23, 0.22], and -0.68 [-1.13, 0.23], , respectively. CONCLUSION: The clinical efficacy of modified Xiaofeng powder in the treatment of CU is better than that of antihistamine drugs, with lower adverse reaction and recurrence rates and higher safety. However, the quality of clinical research included is relatively low, and findings need to be confirmed by high-quality research.

PTGS2: A potential immune regulator and therapeutic target for chronic spontaneous urticaria.

AIMS: Chronic spontaneous urticaria (CSU) is a common and debilitating skin disease that is difficult to control with existing treatments, and the pathogenesis of CSU has not been fully revealed. The aim of this study was to explore the underlying mechanisms of CSU and identify potential treatments. MATERIALS AND METHODS: Microarray datasets of CSU were obtained from Gene Expression Omnibus database. Differentially expressed genes between skin lesions of CSU and normal controls (LNS-DEGs) were identified, and the enrichment analyses of LNS-DEGs were performed. Hub genes of LNS-DEGs were selected by protein-protein interaction analysis. The co-expression and transcriptional regulatory networks of hub genes were conducted using GeneMANIA and TRRUST database, respectively. CIBERSORT was utilized for immune cell infiltration analysis. Experimental validation was performed by ß-hexosaminidase release examination and passive cutaneous anaphylaxis (PCA) mouse model. KEY FINDINGS: A total of 247 LNS-DEGs were identified, which were enriched in cell migration, cell chemotaxis, and inflammatory pathways such as TNF and interleukin (IL) -17 signaling pathway. Among LNS-DEGs, seven upregulated (PTGS2, CCL2, IL1B, CXCL1, IL6, VCAM1, ICAM1) and one downregulated hub gene (PECAM1) were selected. Immune infiltration analysis identified eight different immune cells, such as activated/resting mast cells and neutrophils. Furthermore, PTGS2, encoding cyclooxygenase 2 (COX2), was selected for further validation. COX2 inhibitor, celecoxib, significantly inhibited mast cell degranulation, and reduced vascular permeability and inflammatory cytokine expression in PCA mouse model. SIGNIFICANCE: PTGS2 may be a potential regulator of immunity and inflammation in CSU. Targeting PTGS2 is a new perspective for CSU treatment.

Impact of Chronic Spontaneous or Inducible Urticaria on Occupational Activity.

The impact of chronic urticaria on work has been scarcely reported, whereas its peak incidence is between the ages of 20 and 40. The aim of this study was to assess the occupational impact of chronic urticaria and its treatment, by combining objective and patient-reported data. A monocentric observational study was performed using questionnaires over a 1-year period from 2021 to 2022 in chronic urticaria patients who were in a period of professional activity and agreed to participate. Of the 88 patients included, 55.7% assessed the occupational impact of their chronic urticaria as significant, and even more severe when chronic urticaria was poorly controlled. Some 86% of patients had symptoms at work, in a third of cases aggravated by work. However, occupational physical factors were not associated with an aggravation of inducible chronic urticaria. A total of 20% reported treatment-related adverse effects affecting their work. Despite low absenteeism, presenteeism and reduced productivity were important (> 20%). Six patients (6.8%) had difficulties keeping their work. For 72.7% of the patients, the occupational physician was not informed. The occupational impact of chronic urticaria should be discussed during consultations, particularly when it is insufficiently controlled. The occupational physician should be informed in order to support patients' professional project.

Clinical Features and Outcomes of Acute versus Chronic Urticaria Triggered by COVID-19 Infection.

OBJECTIVE: Although acute urticaria (AU) and urticaria-like rash are commonly reported with COVID-19 infection, chronic spontaneous urticaria (CSU) triggered by COVID-19 is rare. The authors compared the features of COVID-19 infection-induced chronic CSU and AU to determine which patients' COVID-19 infection leads to CSU and possible indicators of chronicity. METHODS: The authors retrieved the charts of patients diagnosed with AU or CSU following COVID-19 at the Urticaria Centers of Reference and Excellence and compared patients in terms of demographic characteristics, length of time between infection and onset of urticaria, duration of urticaria, COVID-19 disease severity, laboratory test results, vaccination, and treatment status. RESULTS: A total of 92 patients were included in the study: 7 with CSU following COVID-19 and 85 with AU after COVID-19. The mean duration of urticaria for CSU and AU following COVID-19 was 13.0 ± 6.0 months and 7.1 ± 3.4 days, respectively. The average time between COVID-19 and the start of urticaria was longer in the CSU group (20.7 ± 3.9 days vs 4.5 ± 2.8 days, respectively; P = .000). No between-group differences were found for any other parameters. CONCLUSIONS: The onset of urticaria more than 2 weeks after COVID-19 infection may serve as an indicator for urticaria chronicity beyond 6 weeks and may help physicians predict the possible course of urticaria associated with COVID-19 infection. The relevance of basopenia and eosinopenia needs to be determined.

[Approved therapies and their effects on the main symptoms of urticaria : When symptom control of itchy wheals is not adequate-does updosing help?] / Zugelassene Therapien und ihre Wirkung auf die Leitsymptome der Urtikaria : Hilfreiche Therapieoptionen, wenn juckende Quaddeln nicht weichen ­ Viel hilft viel?

International guidelines for the treatment of chronic spontaneous urticaria support the updosing of second-generation antihistamines to four times of the approved dose when adequate symptom control cannot be achieved with the standard dosage. However, this recommendation is primarily based on expert opinions, and there is a lack of large, well-designed, double-blind clinical trials. Most the existing trials provide insufficient data, and due to the heterogeneity of the conducted trials on antihistamine effects (definition of control, design, quality, lack of an active comparator, no placebo arm, small sample size, outcomes) and their short duration, comparative analysis is challenging. However, it can be concluded that the use of modern second-generation antihistamines is both effective and safe based on the available data and our own long-term experiences in the specialized outpatient clinic of a university dermatology department, even though increased dosages (up to fourfold as per the current international guidelines) may be necessary for symptom control. Another therapeutic option for refractory symptoms in chronic spontaneous urticaria is subcutaneous administration of omalizumab at a dosage of 300 mg at 4­week intervals as a very safe and effective treatment.

[Spontaneous remission of urticaria: does it exist and if so, when?] / Spontanremission der Urtikaria: Gibt es das, und wenn ja, wann?

BACKGROUND: Urticaria mostly occurs acutely with a very high probability of spontaneous remission. When it persists for more than 6 weeks a chronic urticaria is manifest, which occurs either spontaneously or inducible by specific triggers. The underlying mechanisms are not fully understood but recent research points to defined pathogenetic factors. QUESTION AND AIM: Whether spontaneous remission is possible in urticaria is summarized descriptively in this review, and suggestions are given for the "step down" of urticaria treatment after remission. The mechanisms including autoallergic, immunoglobulin E (IgE)-dependent type I reactions and autoimmune, activating IgG-dependent type IIb reactions are presented. These are discussed in the context of spontaneous remission and the possibilities of induced remission.

UCOMB-real life data: treatment strategies for chronic urticaria patients with comorbidities.

BACKGROUND: There is a lack of real-life safety data on treatment options for chronic urticaria in the presence of comedication and comorbidities. METHODS: We present a single-center UCARE pilot study of 212 outpatients with chronic urticaria. Patients were divided into three groups according to different CU therapies according to international guidelines. RESULTS: Of 212 patients, 108 (mean age 48.9 years, 71.3% female) had 59 comorbidities, including cardiovascular, autoimmune and malignant diseases. Patients were followed for a mean of 24.6 months (SD ± 21.3). Urticaria therapies were divided into three groups: A: 105 (97.2%) with omalizumab and 2nd generation antihistamines), B: 16 patients (14.8%): dual therapy with antihistamines and cyclosporine in 10 (9.3%), montelukast in five (4. 6%), dapsone in four (3.7%), hydroxychloroquine in one patient (0.9%), C: 12 (11.1%) patients received a third drug for 4.9 months (SD ± 3.2) and one quadruple therapy (2.1 months). 10 out of 12 (83.3%) patients received montelukast, two (16.7%) cyclosporine, two (16.7%) dapsone and one (8.3%) hydroxychloroquine as a third drug for chronic urticaria. CONCLUSIONS: Combining treatment modalities for chronic urticaria and comorbidities are available and feasible with a good safety profile.

Total IgE as a biomarker of omalizumab response in chronic spontaneous urticaria: A meta-analysis.

Background: Omalizumab is approved for the treatment of chronic spontaneous urticaria (CSU) that is refractory to antihistamines. Total immunoglobulin E (IgE) levels have emerged as a possible biomarker to predict response to omalizumab. However, the existing literature is heterogenous, with conflicting conclusions with regard to the role of total IgE levels. Objective: We sought to clarify the role of evaluating total IgE levels in patients with CSU by performing a meta-analysis on the existing literature to determine if meaningful changes exist between responders and nonresponders to omalizumab. Methods: A total of 68 unique citations were returned and screened by two independent reviewers. Editorials, reviews, and case reports were excluded, and a total of 33 original articles were identified and underwent secondary evaluation. Studies that present mean ± standard deviation total IgE levels and/or 95% confidence intervals (CI) were included, whereas studies with < 25 subjects were excluded. Three studies ultimately met these criteria. Results: We found a mean difference in total IgE levels between those who responded to omalizumab versus those without a response of 49.76 (95% CI, 7.13-92.38; p = 0.02), which demonstrated higher mean IgE values in responders compared with nonresponders. Conclusion: This study presents additional evidence that supports evaluation of total IgE levels as it pertains to response to omalizumab therapy in CSU. When considering the current evidence, it seems reasonable to consider the baseline total IgE level as a biomarker to predict the treatment response to omalizumab. Based on the existing literature, we cannot conclude at what threshold nonresponse is more likely to occur.

Cold-induced anaphylaxis triggered by drinking cold water.

Cold urticaria is an inducible urticaria in which hives and angioedema appear after exposure to cold. The symptoms of cold urticaria often are limited to hives/angioedema. However, in up to 20% of cases, cold exposure may trigger anaphylaxis. We report the case of an 11-year-old boy previously diagnosed with chronic spontaneous urticaria who developed facial swelling, itchy hives, difficulty in breathing, vomiting and abdominal pain within 5 minutes of drinking cold water. He received a standard dose of non-sedating second-generation antihistamines at home. He was observed in the emergency room for 2 hours and discharged with an epinephrin autoinjector. During the subsequent outpatient clinic visit, an ice cube test was performed which confirmed the new diagnosis of comorbid cold-induced chronic urticaria. On further questioning, the parents reported occurrence of hives following swimming in the swimming pool. Cold-induced urticaria should be suspected in cases of anaphylaxis associated with cold exposure. Patients with chronic forms of urticaria who present with new anaphylaxis should be assessed for a potential concomitant cold-induced form.

[Which augmentation and trigger factors are relevant in urticaria?] / Welche Augmentations- und Triggerfaktoren sind bei der Urtikaria relevant?

The aim of this review is to present relevant trigger as well as augmentation factors that can induce or exacerbate urticaria on the basis of a current, PubMed-based literature search. In addition to a brief description of relevant influencing factors in acute and chronic inducible urticaria, the focus will be on chronic spontaneous urticaria. In particular, the aggravating role of medication, stress, food, psychological and metabolic comorbidities, infections and inflammation as well as hormonal processes will be discussed.

Risk calculator of the clinical response to antihistamines in chronic urticaria: Development and internal validation.

Early detection of CSU patients with low probability of a clinical response with antihistamines could undergo prompt initiation of therapeutic alternatives. The aim of the study was to develop and internally validate a model for predicting the clinical response to antihistamines in adult patients with chronic spontaneous urticaria (CSU), who consult allergology and dermatology care centers. A cohort of CSU patients, recruited from four participating centers, were followed up for 12 months. Fifteen candidate variables were selected to be included in the multivariate model and then internal validation was done with bootstrap analysis with 1000 simulations. The outcome variable, clinical response to antihistamines, was evaluated with the UAS (Urticaria Activity Score) scale for seven days: "No response to antihistamines" was defined as UAS7 ≥7 points after at least one month with a maximum dose of antihistamines, while "Response to antiH1" was defined as UAS7 ≤6 points for at least three months with the use of antiH1. A total of 790 patients were included. Among the different models analyzed, the model that included age, angioedema, anxiety/depression, time with the disease, NSAIDs (Non-steroidal anti-inflammatory drugs) intolerance, and UAS7 baseline was considered the one with the best performance (accuracy 0.675, HL 0.87, AUC 0.727). The internal validation analyses demonstrated good consistency of the model. In conclusion, this prediction model identifies the probability of response to antihistamines in patients with chronic spontaneous urticaria. The model could be useful for a personalized therapeutic approach according to individual patient risk.

Atopy in chronic urticaria: an important yet overlooked issue.

Chronic urticaria (CU) is one of the most common dermatological diseases and has a significant impact on the quality of life of patients. However, the pathogenesis of this disease remains unclear. Autoimmunity in chronic spontaneous urticaria (CSU) has received considerable attention and has been studied previously. Atopy is an important characteristic of CU; however, it has not been fully recognized. Atopy predisposes individuals to immune responses to allergens, leading to type 2 inflammation and immunoglobulin E (IgE) overproduction. Compared with healthy individuals, patients with CU have a higher proportion of atopy, and an atopic background is correlated with the clinical characteristics of CU. The total IgE levels in patients with CU is significantly higher than those in healthy individuals. Although its level is not higher than that in classic allergic diseases, it is closely related to CU. Exogenous allergens, auto-allergens, and specific IgEs, which are closely related to atopy, have been reported, and their roles in CU pathogenesis are also being studied. Local and systemic atopic inflammation is present in patients with CU. This review summarizes the current knowledge regarding atopy and CU, speculating that there are CU subtypes, such as atopic CSU or atopic chronic inducible urticaria (CIndU) and that atopy may be involved in the pathogenesis of CU. These findings provide a new perspective for a comprehensive understanding of the clinical features of CU and further research regarding its pathogenesis.

[Recognition and management of relevant comorbidities in chronic spontaneous urticaria]. / Erkennen und Management relevanter Komorbiditäten bei chronischer spontaner Urtikaria.

Various mechanisms contributing to the activity of chronic spontaneous urticaria (CU) have been postulated. Associated comorbidities are increasingly leading to the discovery of further signaling pathways which may support the activity of chronic urticaria or contribute to low-grade systemic inflammation. Moreover psychoimmunological factors may also be involved. The aim of this work is to improve the clinical care of patients with CU by increasing knowledge regarding optional influencing factors due to comorbidities and to possibly influence disease activity. Chronic urticaria due to autoimmune mechanisms may dispose to other autoimmune diseases, especially autoimmune thyroiditis, which can trigger chronic disease. Association of CU with metabolic syndrome has received little attention to date. Obesity may contribute to low-grade systemic inflammation by cytokine-secreting adipose tissue and hence to mediator-release of mast cells. Furthermore, neuroimmunological pathways, especially increased release of substance P, an activating ligand of Mas-related G protein-coupled receptor X2 (MRGPX2) on mast cells, should be addressed when optimizing therapy.

Beyond Allergies-Updates on The Role of Mas-Related G-Protein-Coupled Receptor X2 in Chronic Urticaria and Atopic Dermatitis.

Mast cells (MCs) are an important part of the immune system, responding both to pathogens and toxins, but they also play an important role in allergic diseases, where recent data show that non-IgE-mediated activation is also of relevance, especially in chronic urticaria (CU) and atopic dermatitis (AD). Skin MCs express Mas-related G-protein-coupled receptor X2 (MRGPRX2), a key protein in non-IgE-dependent MC degranulation, and its overactivity is one of the triggering factors for the above-mentioned diseases, making MRGPRX2 a potential therapeutic target. Reviewing the latest literature revealed our need to focus on the discovery of MRGPRX2 activators as well as the ongoing vast research towards finding specific MRGPRX2 inhibitors for potential therapeutic approaches. Most of these studies are in their preliminary stages, with one drug currently being investigated in a clinical trial. Future studies and improved model systems are needed to verify whether any of these inhibitors may have the potential to be the next therapeutic treatment for CU, AD, and other pseudo-allergic reactions.