Type I and type IIb autoimmune chronic spontaneous urticaria: Using common clinical tools for endotyping patients with CSU

Adaptation and Linguistic Validation of Angioedema PROMs in Latvian for Assessing Recurrent Angioedema

Background: Angioedema (AE) is a localized, non-pitting swelling affecting subcutaneous and/or submucosal tissues. Despite varying underlying mechanisms, AE significantly impacts patients' quality of life (QoL), which is closely linked to disease activity and control. Objectives: This study aimed to translate and linguistically validate the angioedema activity score (AAS), angioedema control test (AECT), and angioedema quality of life (AE-QoL) questionnaires into Latvian, and to use these validated tools to assess disease activity, control, and quality of life within the study population. Methods: PROMs, including the AECT, AAS, and AE-QoL, underwent a standardized linguistic validation process. Patients with hereditary angioedema (HAE), mast cell-mediated angioedema (AE-MC), and angioedema of unknown origin (AE-UNK) were recruited from two separate studies conducted at Riga Stradiņš University. Results: We enrolled 41 participants (90.2% women) with a mean age of 46.3 years. AE-MC was the most common (63.4%), followed by HAE (19.5%) and AE-UNK (17.1%). The mean AAS score was 15.8, with no significant differences regarding AE type, gender, or age. The mean AECT score was 8.29, revealing significant gender differences (women: 7, men: 13.5). The AE-QoL total score was 45.5, with significant gender differences in most domains. Strong correlations were found between AE-QoL scores and both AAS and AECT, highlighting the impact of both disease activity and control on QoL. Conclusions: The Latvian adaptation of the AAS, AECT, and AE-QoL questionnaires effectively assesses AE activity, control, and disease-related QoL. Our study reveals poor disease control, underscoring the need for tailored interventions and regular PROM evaluations, with the Latvian version of the AE-QoL questionnaire identifying five distinct domains compared to four in the original version.

Eosinophilic cationic protein and D-Dimer are potential biomarkers to predict response to antihistamines but not to omalizumab in chronic spontaneous urticaria

INTRODUCTION

Biomarkers that could reliably anticipate the effectiveness of antihistamines and omalizumab in treating chronic spontaneous urticaria (CSU) have not been conclusively identified. Our objective was to examine how eosinophilic cationic protein (ECP), tryptase, D-dimer, and total Immunoglobulin E (IgE) impact the response to antihistamine and omalizumab treatments in individuals with CSU.

METHODS

In this cross-sectional retrospective study, CSU patients that had undergone treatment with either antihistamines or omalizumab for a minimum of 12 weeks between 2015 and 2021 at an Allergy and Immunology Department were analyzed. Several demographic and laboratory parameters including eosinophil counts, mean platelet volüme (MPV), sedimentation, C-reactive protein (CRP), antinuclear antibodies (ANA) and Anti-thyroperoxidase (Anti-TPO) and total IgE, tryptase, ECP and D-dimer were retrived from patient files. The association of these biomarkers with Urticaria Control Test (UCT) and the effect of these biomarkers on treatment response were evaluated. Treatment response was assessed using the UCT, with a score of UCT ≥ 12 indicating a responder and UCT < 12 indicating a non responder.

RESULTS

The patients in the omalizumab group were older, had a longer disease duration and had worse urticaria control (lower baseline UCT scores). 421 patients were treated with antihistamines and 88 patients were treated with omalizumab. ECP was found to be inversely correlated with baseline UCT (p < 0.001 r=-0.268). ECP and D-dimer levels of non-responder patients in the antihistamine group were significantly higher than in responder patients (ECP: 49 ng/mL vs 28.1 ng/mL, p < 0.001) (D-dimer: 0.60 mg/L vs 0.30 mg/L, p < 0.001), while there were no significant difference in terms of tryptase and total IgE. These four biomarkers were similar, in omalizumab responders and non responders.

CONCLUSION

In this study with CSU, we looked at predictors of responses to treatments. ECP can serve as a marker of poor urticaria control and may predict antihistamine refractoriness along with D-dimer.

Chronic Spontaneous Urticaria: A Review

Importance

Chronic spontaneous urticaria affects approximately 1% of the general population worldwide, including approximately 3 million people in the US, impairs patients' quality of life, and is associated with multiple comorbidities.

Observations

Chronic spontaneous urticaria affects patients of any age but is most common in females aged 30 to 50 years. Diagnosis is based on clinical presentation, ie, spontaneously recurring wheals, angioedema, or both. Chronic spontaneous urticaria persists for more than 1 year in most patients (1 or repeated episodes) and may present with comorbidities including chronic inducible urticaria (>10%), autoimmune thyroiditis (approximately 20%), metabolic syndrome (6%-20%), and anxiety (10%-31%) and depression (7%-29%). Known autoimmune endotypes (subtypes of urticaria defined by distinct pathogenesis) of chronic spontaneous urticaria are mediated by mast cell-activating IgE and/or IgG autoantibodies (>50%). Approximately 40% of patients with chronic spontaneous urticaria have a Dermatology Life Quality Index of more than 10, corresponding to a very large or extremely large negative effect on quality of life. Second-generation H1 antihistamines are first-line treatment; partial or complete response, defined as a reduction in urticaria symptoms of greater than 50%, is observed in approximately 40% of patients. The 2022 international urticaria guideline recommends the monoclonal anti-IgE antibody omalizumab as second-line treatment for antihistamine-refractory chronic spontaneous urticaria. However, at least 30% of patients have an insufficient response to omalizumab, especially those with IgG-mediated autoimmune urticaria. Cyclosporine, used off-label, can improve symptoms in approximately 54% to 73% of patients, especially those with autoimmune chronic spontaneous urticaria and nonresponse to omalizumab, but has adverse effects such as kidney dysfunction and hypertension.

Conclusions and Relevance

Chronic spontaneous urticaria is an inflammatory skin disease associated with medical and psychiatric comorbidities and impaired quality of life. Second-generation H1 antihistamines are first-line treatment, omalizumab is second-line treatment, and cyclosporine is third-line treatment for chronic spontaneous urticaria.

Disease modification in chronic spontaneous urticaria

Chronic spontaneous urticaria (CSU) is a debilitating, inflammatory skin condition characterized by infiltrating immune cells. Available treatments are limited to improving the signs and symptoms. There is an unmet need to develop therapies that target disease-driving pathways upstream of mast cell activation to inhibit or delay the progression of CSU and associated comorbidities. Here, we aim to define disease modification due to a treatment intervention and criteria that disease-modifying treatments (DMTs) must meet in CSU. We have defined disease modification in CSU as a favorable treatment-induced change in the underlying pathophysiology and, therefore, the disease course, which is clinically beneficial and enduring. A DMT must fulfil the following criteria: (1) prevents or delays the progression of CSU, (2) induces long-term, therapy-free clinical remission, which is the sustained absence of CSU signs and symptoms without the need for treatment, and (3) affects the underlying mechanism of CSU, as demonstrated by an effect on disease-driving signals and/or a biomarker. DMTs in CSU should slow disease progression, achieve long-lasting disease remission, target disease-driving mechanisms, reduce mast cell-activating IgE autoantibodies, target cytokine profile polarization, and normalize the gut microbiome and barrier. Treating CSU at the immune system level could provide valuable alternatives to pharmacotherapy in CSU management. Specific DMTs in CSU are yet to be developed, but some show potential benefits, such as inhibitors of Bruton's Tyrosine Kinase, IL-4 and IL-13. Future therapies could prevent CSU signs and symptoms, achieve long-term clinical benefits after discontinuing treatment, and prevent associated concomitant disorders.

Lin-CD117+CD34+FcεRI+ progenitor cells are increased in chronic spontaneous urticaria and predict clinical responsiveness to anti-IgE therapy

BACKGROUND

Chronic spontaneous urticaria (CSU) is a common, debilitating skin disorder characterized by recurring episodes of raised, itchy and sometimes painful wheals lasting longer than 6 weeks. CSU is mediated by mast cells which are absent from peripheral blood. However, lineage-CD34hiCD117int/hiFcεRI+ cells in blood have previously been shown to represent a mast cell precursor.

METHODS

We enumerated FcεRI-, FcεRI+ and FcεRIhi lineage-CD34+CD117+ cells using flow cytometry in blood of patients with CSU (n = 55), including 12 patients receiving omalizumab and 43 not receiving omalizumab (n = 43). Twenty-two control samples were studied. Disease control and patient response to omalizumab was evaluated using the urticaria control test. We performed single-cell RNA sequencing (scRNA-Seq) on lineage-CD34hiCD117hi blood cells from a subset of patients with CSU (n = 8) and healthy controls (n = 4).

RESULTS

CSU patients had more lineage-CD34+CD117+FcεRI+ blood cells than controls. Lineage-CD34+CD117+FcεRI+ cells were significantly higher in patients with CSU who had an objective clinical response to omalizumab when compared to patients who had poor disease control 90 days after initiation of omalizumab. scRNA-Seq revealed that lineage-CD34+CD117+FcεRI+ cells contained both lymphoid and myeloid progenitor lineages, with omalizumab responsive patients having proportionally more myeloid progenitors. The myeloid progenitor lineage contained small numbers of true mast cell precursors along with more immature FcεRI- and FcεRI+ myeloid progenitors.

CONCLUSION

Increased blood CD34+CD117+FcεRI+ cells may reflect enhanced bone marrow egress in the setting of CSU. High expression of these cells strongly predicts better clinical responses to the anti-IgE therapy, omalizumab.

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.

Characteristics and Clinical Significance of Atopy in Chronic Spontaneous Urticaria: A Cross-Sectional Observational Study

INTRODUCTION

Atopy is an important and non-negligible clinical phenomenon in chronic spontaneous urticaria (CSU). However, the characteristics and clinical significance of atopy in patients with CSU have not been fully described. This study aimed to analyze the characteristics and clinical significance of atopy in patients with CSU.

METHODS

A descriptive cross-sectional design was used. The study enrolled 176 patients with CSU. All enrolled patients underwent total IgE, specific IgE, and autologous serum skin tests (ASSTs). The relationships between atopy, the demographic and clinical data of patients with CSU, and the response to ASST were analyzed in detail; the distribution of allergens in atopic CSU was also analyzed.

RESULTS

Atopy was confirmed in 48.9% of patients with CSU. Patients with atopic CSU were more likely than patients with non-atopic CSU to have dermatographism (57.0% vs. 41.1%, p < 0.05), history of urticaria (37.2% and 18.9%, respectively; p < 0.01), angioedema (39.5% and 24.4%, respectively; p < 0.05), and anaphylaxis (7/86 and 1/90, respectively; p < 0.05). Atopy was not associated with ASST response, disease duration, or response to antihistamine treatment in patients with CSU, nor was it associated with the urticaria activity score (UAS7), chronic urticaria quality of life questionnaire (CU-Q2oL), or pruritus visual analog scale (VAS) scores (all p < 0.05). The most common allergen in patients with atopic CSU was dust mites, followed by animal food allergens, tree/grass pollen, and cockroaches.

CONCLUSIONS

Although larger prospective studies are needed to confirm these results, our study found atopy occurred in nearly half of patients with CSU, and preliminarily links atopy to CSU, suggesting it as a potential risk factor for angioedema, anaphylaxis, and recurrent urticaria, mirroring allergen patterns in other allergic disease.

Acute Urticaria: Symptoms, Causes, and Evaluation of Phenotypes Prone to Chronicity

INTRODUCTION

Urticaria is a condition that is characterized by the development of wheals (hives), angioedema, or both. If symptoms persist for less than 6 weeks, it is classified as acute urticaria (AU), and if they persist for longer than 6 weeks, it is classified as chronic urticaria (CU). Disease activity is evaluated using validated patient-reported outcome measures (PROMs) such as the 7-day urticaria activity score (UAS-7) and urticaria control test (UCT). In this study, we aimed to determine whether there was a difference between patients with chronic and recovered urticaria in terms of age, sex, symptoms, disease severity, disease control, and triggering factors by following patients with AU for 6 months.

METHODS

The routine tests were requested at the first admission of the patients. If previously examined, anti-thyroid peroxidase (anti-TPO), anti-nuclear antibody, etc., were recorded. After the first examination, the patients were evaluated again using a visual analog scale (VAS), UCT, UAS-7, and medication scores (MSs) in the 1st, 3rd, and 6th months.

RESULTS

One hundred nine (F/M: 80/29) patients were included in the study. Twenty-seven patients had a previous history of AU, 22 of these patients were evaluated as having recurrent AU, and five became chronic during follow-up. Urticaria continued in 22 of 82 patients who presented with first-attack AU in the 3rd month and 17 in the 6th month. We had a chronicity rate of 24.7%. It was determined that having positive anti-TPO increased the risk of CU 1.69 times. A statistically significant improvement was found in the mean VAS, UCT, UAS-7, and MSs evaluated in the 1st, 3rd, and 6th months of patients with CU compared with baseline.

CONCLUSION

AU is a common disease and usually heals in a short time without becoming chronic. Studies on the causes of chronicity are limited. Testing anti-TPO in patients presenting with AU may be useful in terms of disease course and risk of chronicity.