Chronic inducible urticaria subtypes in children: Clinical features and prognosis

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.

Shedding light on dermographism: a narrative review

Dermographism is a common subtype of chronic urticaria. It generally manifests as a linear wheal after scratching or friction, with or without angioedema. The pathophysiology is not clear, but currently, we believe that the stimulation of the skin by mechanical stress leads to the activation of mast cells, which provoke the release of histamine and pro-inflammatory mediators, ultimately forming wheal along the stressed area. The gold standard for diagnosis is a medical history and provocation test or dermatographic test. As one of the subtypes of chronic urticaria, the Urticaria Control Test (UCT), Chronic Urticaria Quality of Life questionnaire (CU-Q2oL), and Dermatology Life Quality Index (DLQI) are also effective tools for evaluating disease control in dermographism patients. In addition to avoiding triggers, nonsedating H1 antihistamines are the first-line medications recommended by EAACI and other guidelines; for those who do not respond to standard doses, the recommended dosage can be increased up to 4 times. When necessary, the off-label use of omalizumab can be considered, and some drugs with potential therapeutic effects are still being explored. However, there is still a lack of biomarkers for predicting disease severity, efficacy, and prognosis. Here, we review what we know about dermographism and some points that need exploration in the future.

Chronic Urticaria in Special Populations: Pediatric, Pregnancy, and the Elderly

Chronic urticaria is an inflammatory skin disorder defined by the presence of evanescent erythematous pruritic wheals, angioedema, or both. While treatment guidelines are continuing to become more clearly defined, there is still a gap in the medical literature surrounding chronic spontaneous urticaria (CSU) treatment in vulnerable populations such as children (aged 0-18 years), pregnant women, and the elderly (aged >65 years). The purpose of this review is to provide an update on CSU in each of these special population categories by defining prevalence, identifying diagnostic considerations, and exploring current and future management options.

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.

Immunopathogenesis of urticaria: a clinical perspective on histamine and cytokine involvement

BACKGROUND

Urticaria is a clinical condition characterized by the appearance of wheals (hives), angioedema, or both. Over the last several decades, a better understanding of the mechanisms at play in the immunopathogenesis of urticaria has underscored the existence of numerous urticaria subtypes. Separating the different kinds of urticaria explicitly helps find the best detection method for the management of this skin disorder. Subtypes of urticaria also include both spontaneous and physical types. The conventional ones include spontaneous urticaria, constituting both acute and chronic urticaria. Therefore, a broad and effective therapy is essential for the diagnosis and treatment of urticaria.

METHODS

To understand the immunopathogenesis of urticaria, various databases, including PubMed, Scopus, and Web of Science, were used to retrieve original articles and reviews related to urticaria. While information on several clinical trials were obtained from clinicaltrials.gov database.

RESULTS

This article highlights the immunopathogenesis involved in the intricate interaction between cellular infiltration, immune reactions, coagulation cascades, and autoantibodies that underlie urticaria's pathophysiology.

CONCLUSION

The recent progress in understanding urticaria can help to understand the intricate characteristics in the immunopathogenesis of urticaria and could play a beneficial role in the management of urticaria.

[Spontaneous remission of urticaria: does it exist and if so, when?]

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.

Evaluation of Pediatric Chronic Urticaria with Emphasis on Clinical and Laboratory Characteristics and Treatment Response to Omalizumab: A Real-Life Experience from a Tertiary Allergy Center

Pediatric data on the clinical and etiologic features, treatment response, and use of omalizumab for chronic urticaria (CU) are quite limited. The aim of this study was to evaluate the clinical and demographic characteristics, laboratory findings, and response to treatment of CU in children. Children with a diagnosis of CU between 2019 and 2023 were included in the study. Information on demographic characteristics, clinical features, laboratory tests, provocation tests for inducible urticaria, urticaria activity scores (UAS7), and treatment responses were obtained from patients' medical records. A total of 150 children (50.7% male) with CU were enrolled in the study. A total of 14 (9.3%) patients had autoimmune diseases of which 11 (7.3%) had autoimmune thyroiditis. Overall, 97 (64.7%) patients had chronic spontaneous urticaria (CSU) and 53 (35.3%) had chronic inducible urticaria. A total of 16 patients who remained symptomatic despite high-dose antihistamines were treated with omalizumab, with a good response in 13 (81.3%) and a partial response in 3 (18.7%) patients. CSU accounts for the majority of pediatric CU, with the etiology being in part related to an autoimmune background. This study provides an overview of CU in children and demonstrates the safety and efficacy of treatment with omalizumab.

The many faces of pediatric urticaria

Urticaria is a common disease that can affect individuals of all age groups, with approximately one-quarter of the population experiencing it at least once in their lifetime. Lesions characterized by erythema and itchy hives can appear anywhere on the body. These can vary in size ranging from millimeters to centimeters, and typically clear within 24 h. About 40% of patients with urticaria have accompanying angioedema, which involves localized deep tissue swelling. Urticaria usually occurs spontaneously and is classified into acute and chronic forms, with the latter referring to a condition that lasts for more than 6 weeks. The prevalence of chronic urticaria in the general population ranges from 0.5% to 5%, and it can either be inducible or spontaneous. The most common form of pediatric urticaria is acute and is usually self-limiting. However, a broad differential diagnosis should be considered in children with urticaria, particularly if they also have accompanying systemic complaints. Differential diagnoses of pediatric urticaria include chronic spontaneous urticaria, chronic inducible urticaria, serum sickness-like reaction, urticarial vasculitis, and mast cell disorders. Conditions that can mimic urticaria, including but not limited to cryopyrinopathies, hyper IgD syndrome, Periodic Fever, Aphthous Stomatitis, Pharyngitis and Adenitis (PFAPA), Tumor Necrosis Factor Receptor Associated Periodic Syndrome (TRAPs), and Schnitzler syndrome should also be considered. The many faces of pediatric urticaria can be both easy and confusing. A pragmatic approach relies on clinical foresight and understanding the various forms of urticaria and their potential mimickers. This approach can pave the way for an accurate and optimized diagnostic approach in children with urticaria.

Prevalence and bidirectional association between rhinitis and urticaria: A systematic review and meta-analysis

Background: Rhinitis, allergic rhinitis in particular, and urticaria are both common diseases globally. However, there is controversy with regard to the correlation between rhinitis and urticaria. Objective: To examine the accurate association between rhinitis and urticaria. Methods: Three medical literature data bases were searched from data base inception until January 11, 2022. The prevalence and association between rhinitis and urticaria were estimated by meta-analysis. Quality assessment was performed by using the Newcastle-Ottawa Scale. Pooled odds ratios (OR) with 95% confidence intervals (CI) and pooled prevalence were calculated by using random-effects models. Results: Urticaria prevalence in patients with rhinitis was 17.6% (95% CI, 13.2%-21.9%). The pooled prevalence of rhinitis was 31.3% (95% CI, 24.2%-38.4%) in patients with urticaria, and rhinitis prevalence in patients with acute urticaria and chronic urticaria was 31.6% (95% CI, 7.4%-55.8%) and 28.7% (95% CI, 20.4%-36.9%), respectively. Rhinitis occurrence was significantly associated with urticaria (OR 2.67 [95% CI, 2.625-2.715]). Urticaria and rhinitis were diagnosed based on different criteria, possibly resulting in a potential error of misclassification. Conclusion: Rhinitis and urticaria were significantly correlated. Physicians should be cognizant with regard to this relationship and address nasal or skin symptoms in patients.

Urticaria

Urticaria is an inflammatory skin disorder that affects up to 20% of the world population at some point during their life. It presents with wheals, angioedema or both due to activation and degranulation of skin mast cells and the release of histamine and other mediators. Most cases of urticaria are acute urticaria, which lasts ≤6 weeks and can be associated with infections or intake of drugs or foods. Chronic urticaria (CU) is either spontaneous or inducible, lasts >6 weeks and persists for >1 year in most patients. CU greatly affects patient quality of life, and is linked to psychiatric comorbidities and high healthcare costs. In contrast to chronic spontaneous urticaria (CSU), chronic inducible urticaria (CIndU) has definite and subtype-specific triggers that induce signs and symptoms. The pathogenesis of CSU consists of several interlinked events involving autoantibodies, complement and coagulation. The diagnosis of urticaria is clinical, but several tests can be performed to exclude differential diagnoses and identify underlying causes in CSU or triggers in CIndU. Current urticaria treatment aims at complete response, with a stepwise approach using second-generation H1 antihistamines, omalizumab and cyclosporine. Novel treatment approaches centre on targeting mediators, signalling pathways and receptors of mast cells and other immune cells. Further research should focus on defining disease endotypes and their biomarkers, identifying new treatment targets and developing improved therapies.

Urticaria in a Pediatric Population: A Portuguese Single-Center Cohort Report

Background

Urticaria typically involves the skin and mucosa and is characterized by the development of wheals, angioedema, or both. According to the temporal evolution of the lesions, urticaria is classified as acute (AU) or chronic (CU), depending on whether the episodes last for fewer or more than six weeks, respectively. This study aimed to characterize a group of children and adolescents with urticaria and describe its subtypes, associated comorbidities, treatment, and evolution.

Methodology

This retrospective, observational study included patients aged <18 years who were diagnosed with urticaria in a tertiary teaching hospital in Portugal, and followed up in a Pediatric Allergy Unit, between January 2019 and December 2021.

Results

A total of 43 patients, aged nine months to 16 years were included. Of these, 22 (51%) were males. AU was identified in 12 (28%) cases, chronic spontaneous urticaria in 21 (63%), and physical urticaria (to cold) in four (9%). Autoantibodies were detected in four patients with spontaneous urticaria. In 6% of patients with CU, the episodes were associated with angioedema. Most CU episodes were successfully managed with the recommended or double the recommended dose (48%) of H1 antihistamines. Three patients requiring fourfold higher than the recommended dose of H1 antihistamines remained unresponsive and were started on omalizumab. Associated autoimmune thyroiditis was diagnosed in four patients.

Conclusions

In this cohort of patients, urticaria was equally distributed between the genders and the first-line therapy was second-generation antihistamines, consistent with current guidelines. Universal screening for autoimmune diseases in patients with chronic spontaneous urticaria revealed four cases of thyroiditis, which supports the relevance of this approach when managing CU.

Cold urticaria in a pediatric cohort: Clinical characteristics, management, and natural history

BACKGROUND

Cold urticaria (coldU) is associated with substantial morbidity and risk of fatality. Data on coldU in children are sparse. We aimed to evaluate the clinical characteristics, management, risk of associated anaphylaxis, and resolution rate of coldU in a pediatric cohort. Additionally, we sought to compare these metrics to children with chronic spontaneous urticaria (CSU).

METHODS

We prospectively enrolled children with coldU from 2013-2021 in a cohort study at the Montreal Children's Hospital and an affiliated allergy clinic. Data for comparison with participants with solely CSU were extracted from a previous study. Data on demographics, comorbidities, severity of presentation, management, and laboratory values were collected at study entry. Patients were contacted yearly to assess for resolution.

RESULTS

Fifty-two children with cold urticaria were recruited, 51.9% were female and the median age of symptom onset was 9.5 years. Most patients were managed with second-generation H1-antihistamines (sgAHs). Well-controlled disease on sgAHs was negatively associated with concomitant CSU (adjusted odds ratio (aOR) = 0.69 [95%CI: 0.53, 0.92]). Elevated eosinophils were associated with cold-induced anaphylaxis (coldA; aOR = 1.38 [95%CI: 1.04, 1.83]), which occurred in 17.3% of patients. The resolution rate of coldU was 4.8 per 100 patient-years, which was lower than that of CSU (adjusted hazard ratio = 0.43 [95%CI: 0.21, 0.89], p < 10^-2 ).

CONCLUSION

Pediatric coldU bears a substantial risk of anaphylaxis and a low-resolution rate. Absolute eosinophil count and co-existing CSU may be useful predictive factors.

Prevalence, Management, and Anaphylaxis Risk of Cold Urticaria: A Systematic Review and Meta-Analysis

BACKGROUND

Cold urticaria is a subtype of chronic inducible urticaria (CIndU) associated with significant morbidity and a risk for anaphylaxis. Few studies have assessed the prevalence, management, and prevalence of associated anaphylaxis of cold urticaria.

OBJECTIVES

To evaluate the prevalence of cold urticaria among CIndU and chronic urticaria (CU) cases, to assess the management of cold urticaria, and to determine the prevalence of associated anaphylaxis.

METHODS

We searched PubMed and EMBASE for studies pertaining to cold urticaria and/or CIndU published in the past 10 years. We conducted meta-analyses to evaluate the prevalence of cold urticaria among CIndU and CU cases, the management of cold urticaria with H1-antihistamines and omalizumab, and the prevalence of associated anaphylaxis.

RESULTS

Twenty-two studies were included in the systematic review and 14 in the meta-analysis. The pooled prevalence of cold urticaria among patients with CU and CIndU was 7.62% (95% confidence interval [CI], 3.45% to 15.99%; I² = 98%) and 26.10% (95% CI, 14.17% to 43.05%; I² = 97%), respectively. Cold urticaria was managed by H1-antihistamines in 95.67% (95% CI, 92.47% to 97.54%; I² = 38%) of patients and omalizumab in 5.95% (95% CI , 2.55% to 13.27%; I² = 83%) of patients. The pooled prevalence of anaphylaxis among patients with cold urticaria was 21.49% (95% CI, 15.79% to 28.54%; I² = 69%).

CONCLUSIONS

Cold urticaria constitutes an appreciable proportion of CIndU and CU cases and is predominantly managed with H1-antihistamines; few patients receive omalizumab. Anaphylaxis is common, and an epinephrine autoinjector prescription may be considered.