Chronic urticaria in a health maintenance organization of Buenos Aires, Argentina - new data that increase global knowledge of this disease

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.

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.

Epidemiology of urticaria in China: a population-based study

Background:

Urticaria is a common skin disease characterized by episodes of wheals, and it has a negative effect on patients’ quality of life. Large-scale population-based epidemiological studies of urticaria are scarce in China. The aim of this survey was to determine the prevalence, clinical forms, and risk factors of urticaria in the Chinese population.

Methods:

This survey was conducted in 35 cities from 31 provinces, autonomous regions, and municipalities of China. Two to three communities in each city were selected in this investigation. Participants completed questionnaires and received dermatological examinations. We analyzed the prevalence, clinical forms, and risk factors of urticaria.

Results:

In total, 44,875 questionnaires were distributed and 41,041 valid questionnaires were collected (17,563 male and 23,478 female participants). The lifetime prevalence of urticaria was 7.30%, with 8.26% in female and 6.34% in male individuals (P < 0.05). The point prevalence of urticaria was 0.75%, with 0.79% in female and 0.71% in male individuals (P < 0.05). Concomitant angioedema was found in 6.16% of patients. Adults had a higher prevalence of urticaria than adolescents and children. Living in urban areas, exposure to pollutants, an anxious or depressed psychological status, a personal and family history of allergy, thyroid diseases, and Helicobacter pylori infection were associated with a higher prevalence of urticaria. Smoking was correlated with a reduced risk of urticaria.

Conclusion:

This study demonstrated that the lifetime prevalence of urticaria was 7.30% and the point prevalence was 0.75% in the Chinese population; women had a higher prevalence of urticaria than men. Various factors were correlated with urticaria.

Current and emerging pharmacotherapy for chronic spontaneous Urticaria: a focus on non-biological therapeutics

INTRODUCTION

Chronic spontaneous urticaria (CSU) refers to urticaria (wheals) or angioedema, which occur for a period of six weeks or longer without an apparent cause. The condition may impair the patient's quality of life.

AREAS COVERED

Treatment for CSU is mainly symptomatic. Both AAAAI/ACAAI practice parameters and EAACI/GA2LEN/EDF/WAO guidelines suggest CSU management in a stepwise manner. First-line therapy is with second-generation H₁-antihistamines. Treatment should be stepped up along the algorithm if symptoms are not adequately controlled. Increasing the dosage of second-generation H₁-antihistamines, with the addition of first-generation H₁-antihistamines, H₂ antagonist, omalizumab, ciclosporin A, or short-term corticosteroid may be necessary. New medications are being developed to treat refractory CSU. They include spleen tyrosine kinase inhibitor, Bruton tyrosine kinase inhibitor, prostaglandin D₂ receptor inhibitor, H₄-antihistamine, and other agents. The authors discuss these treatments and provide expert perspectives on the management of CSU.

EXPERT OPINION

Second-generation H₁-antihistamines remain the first-line therapeutic options for the management of CSU. For patients not responding to higher-dose H₁-antihistamines, international guidelines recommend the addition of omalizumab. Efficacy and safety data for newer agents are still pending. Large-scale, well-designed, randomized, double-blind, placebo-controlled trials will further provide evidence on the safety profile and efficacy of these agents in patients with CSU.

Evaluation of serum levels of C-reactive protein, D-Dimer and Autologous Serum Skin Test in patients with Chronic Spontaneous Urticaria in a Brazilian tertiary center : a cross-sectional study

Background

The pathophysiology of urticaria is still poorly understood. Recent studies demonstrate that the activation of coagulation is correlated with the clinical activity of Chronic Spontaneous Urticaria. Coagulation and inflammation are strongly linked.

Objectives

To correlate the severity and activity of Chronic Spontaneous Urticaria with the levels of D-dimer, C-reactive protein, and autologous serum test in patients with Chronic Spontaneous Urticaria.

Methods

The study included 55 patients diagnosed with chronic spontaneous urticaria. D-dimer levels were measured using enzyme-linked fluorescent assay and C-reactive protein levels were measured using the nephelometric method; autologous serum testing was performed on patients who discontinued antihistamine therapy. The severity of the disease was assessed using the urticaria activity score.

Results

patients with severe, spontaneous, and difficult-to-control chronic urticaria had elevated serum levels of D-dimer, as well as a positive autologous serum test. Little correlation was demonstrated between the severity of chronic spontaneous urticaria and the levels of C-reactive protein.

Conclusion

The authors concluded that patients with severe Chronic Spontaneous Urticaria showed signs of activated fibrinolysis. Most patients with high clinical scores had high D-dimer values. Patients with positive results for the autologous serum test also had more severe Chronic Spontaneous Urticaria and needed more drugs to control the disease. Finally, little correlation was found between C-reactive protein levels and disease severity.

Study limitations

The main limitation was the small sample of patients. In the present patients, it was demonstrated that serum D-dimer levels and the autologous serum test can act as predictive markers of severity and activity of Chronic Spontaneous Urticaria.

Investigation of self-reported chronic urticaria among adults in grasslands of northern China

The clinical epidemiological characteristics of chronic urticaria (CU) in different populations were not completely consistent, and the epidemiological characteristics of CU were very complex. At present, there were some patient-based studies on CU, but few natural population-based studied in the world.This study aimed to analysis the prevalence of self-reported CU among adults in grasslands of northern China and its closely related factors.A multistage and proportionately stratified random sampling with a field interviewer-administered survey study was performed together with skin prick tests (SPT) and measurements of the daily pollen count.A total of 3406 subjects completed the study. The prevalence of self-reported CU was 5.61% (n = 191), which was higher in women than that of men (6.91% vs 4.08%, X = 12.785, P < .001). Seasonal or seasonal aggravation CU accounted for 110 (57.59%) patients. Pollen dispersal season was basically consistent with the peak season of CU, but there was no significant difference in the positive rate of pollen SPT between CU with seasonal or seasonal aggravation symptom and CU with free of symptom (X = 0.425, P = .51), as well as between CU with seasonal or seasonal aggravation symptom and perennial CU (X = 0.439, P = .51). Eczema (odds ratio [OR] = 2.807, P < .001), chronic diarrhea (OR = 2.486, P < .01), food allergy history (OR = 1.890, P < .01), history of family allergy (OR = 1.800, P < .001), and conjunctivitis (OR = 1.749, P < .01) were closely related to CU.This investigation provided the factors closely related to CU, and provided certain ideas for further research on the etiology and prevention of CU.

Prevalence of chronic urticaria in children and adults across the globe: Systematic review with meta-analysis

BACKGROUND AND OBJECTIVES

Urticaria is a frequent skin condition, but reliable prevalence estimates from population studies particularly of the chronic form are scarce. The objective of this study was to systematically evaluate and summarize the prevalence of chronic urticaria by evaluating population-based studies worldwide.

METHODS

We performed a systematic search in PUBMED and EMBASE for population-based studies of cross-sectional or cohort design and studies based on health insurance/system databases. Risk of bias was assessed using a specific tool for prevalence studies. For meta-analysis, we used a random effects model.

RESULTS

Eighteen studies were included in the systematic evaluation and 11 in the meta-analysis including data from over 86 000 000 participants. Risk of bias was mainly moderate, whereas the statistical heterogeneity (I² ) between the studies was high. Asian studies combined showed a higher point prevalence of chronic urticaria (1.4%, 95%-CI 0.5-2.9) than those from Europe (0.5%, 0.2-1.0) and Northern American (0.1%, 0.1-0.1). Women were slightly more affected than men, whereas in children < 15 years we did not find a sex-specific difference in the prevalence. The four studies that examined time trends indicated an increasing prevalence of chronic urticaria over time.

CONCLUSIONS

On a global level, the prevalence of chronic urticaria showed considerable regional differences. There is a need to obtain more sex-specific population-based and standardized international data particularly for children and adolescents, different chronic urticaria subtypes and potential risk and protective factors.

Real-life approach and treatment of chronic urticaria in Argentina: A National Survey

The management of chronic urticaria (CU) has been controversial. Recently updated international guidelines propose evidence-based diagnosis and treatment. Nevertheless, dermatologists have heterogeneous approaches to managing CU. To estimate the percentage of dermatologists who have an optimal approach to CU according to the international guidelines, and to explore the variables associated with optimal management a cross-sectional study using a 17-question survey was delivered by email to dermatologists from Argentina. Optimal first, second, and third line treatment were considered when dermatologists chose a nonsedative antihistamine; increased the dosage of nonsedative antihistamines, and added omalizumab, respectively. Logistic regression was used to identify variables associated with optimal management. A total of 165 questionnaires were available for analysis. An optimal first, second, and third-line treatment approach was identified in 50%, 35%, and 15% of the dermatologists, respectively. The dermatologists' age being above 55 years old (OR: 0.12, 95% CI: 0.01-0.99, p .005) and having more than 5 years of expertise (OR: 0.4, 95% CI: 0.19-0.81, p .001) were significantly associated with a suboptimal approach in second-line treatment. We could not find variables associated with an optimal first or third-line treatment. The real-life management of CU in Argentina is partly suboptimal according to the international guidelines.

Prevalence estimates for chronic urticaria in the United States: A sex- and age-adjusted population analysis

BACKGROUND

Disease burden in chronic urticaria (CU) is poorly understood.

OBJECTIVE

To estimate standardized overall and sex-, age-, and race-specific prevalence estimates for CU among adults in the United States.

METHODS

A cross-sectional analysis with electronic health records data for a demographically heterogeneous population-based sample of >55 million patients across all 4 census regions.

RESULTS

The overall CU prevalence was 0.23%, or 230 CU cases/100,000 adults. The adjusted prevalence in women was 310 (95% confidence interval [CI] 307-312) cases/100,000 adults, more than twice that of men (146 [95% CI 143-148] cases/100,000 adults, P < .001). CU prevalence was highest among patients aged 40-49 years (256 [95% CI 252-261] cases/100,000 adults) and 50-59 years (246 [95% CI 242-251] cases/100,000 adults) compared with all other age groups (P < .0001). Adjusted prevalences for black (292 [95% CI 285-298] cases/100,000 adults) and other (331 [95% CI 323-338] cases/100,000 adults) patients were higher than that for white patients (262 [95% CI 260-264] cases/100,000 adults; P < .001).

LIMITATIONS

Use of administrative data has the potential to underestimate burden.

CONCLUSION

There are >500,000 people estimated to have CU in the United States, most of whom are women or adults ≥40 years of age.