Chronic urticaria: recent advances

Immune cells in skin inflammation, wound healing, and skin cancer

Given the self-evident importance of cutaneous immunity in the maintenance of body-surface homeostasis, disturbance of the steady-state skin is inextricably intertwined with dysfunction in cutaneous immunity. It is often overlooked by people that skin, well-known as a solid physical barrier, is also a strong immunological barrier, considering the abundant presence of immune cells including lymphocytes, granulocytes, dendritic cells, and macrophages. What's more, humoral immune components including cytokines, immunoglobulins, and antimicrobial peptides are also rich in the skin. This review centers on skin inflammation (acute and chronic, infection and aseptic inflammation), wound healing, and skin cancer to elucidate the elaborate network of immune cells in skin diseases.

The Promising Role of Polyphenols in Skin Disorders

The biochemical characteristics of polyphenols contribute to their numerous advantageous impacts on human health. The existing research suggests that plant phenolics, whether consumed orally or applied directly to the skin, can be beneficial in alleviating symptoms and avoiding the development of many skin disorders. Phenolic compounds, which are both harmless and naturally present, exhibit significant potential in terms of counteracting the effects of skin damage, aging, diseases, wounds, and burns. Moreover, polyphenols play a preventive role and possess the ability to delay the progression of several skin disorders, ranging from small and discomforting to severe and potentially life-threatening ones. This article provides a concise overview of recent research on the potential therapeutic application of polyphenols for skin conditions. It specifically highlights studies that have investigated clinical trials and the use of polyphenol-based nanoformulations for the treatment of different skin ailments.

Polyphenols from Mediterranean Plants: Biological Activities for Skin Photoprotection in Atopic Dermatitis, Psoriasis, and Chronic Urticaria

Polyphenols are a diverse class of natural compounds that are widely distributed in various fruits, vegetables, and herbs. They possess antioxidant and anti-inflammatory properties and bring benefits in the prevention and treatment of various diseases. Studies suggested that polyphenols may improve cardiovascular health and may have neuroprotective effects. The Mediterranean region is a vast area. Although the territory encompasses a wide variety of cultures and dietary patterns, there are some commonalities in terms of the plant-based foods and their polyphenol content. Such polyphenols have been studied for their potential photoprotective effects on the skin. We focused on nutraceutical effects of Mediterranean plants in skin photoprotection in atopic dermatitis, psoriasis, and chronic urticaria. Results highlight the importance of exploring natural compounds for therapeutic purposes. The wide variety of polyphenols found in different foods and plants allows for a diverse range of pharmacological effects. The Mediterranean diet, rich in polyphenol-containing foods, is associated with a lower incidence of various chronic diseases, including dermatological conditions. While more research is needed to fully understand the mechanisms of action and optimal dosing of polyphenols, there is initial evidence to support their potential use as adjunctive therapy for atopic dermatitis, psoriasis, and chronic urticaria.

Dermatologic manifestations of thyroid disease: a literature review

Introduction

Thyroid hormone is considered one of the key regulatory hormones for skin homeostasis. Multiple organs are affected by the release of peripheral thyroid hormones (T4 and T3) further regulating various functions at a cellular level. Specifically, skin is considered an important target organ in which the thyroid hormone has a significant impact. Multiple skin diseases are associated with thyroid hormone dysregulation. However, other striking dermatologic manifestations are seen in nails and hair as well. Hypothyroidism, hyperthyroidism, and thyroid cancer can have an array of cutaneous manifestations, and we present the recent updates in this field.

Methods

A PubMed search was performed for updates in any new skin disease findings and treatments between 2010 and 2022. Research published in the past decade and previously known foundational skin findings associated with thyroid disease were presented in this review.

Conclusion

Cutaneous manifestations of thyroid disease is one of the first notable signs of thyroid hormone dysregulation. This article reviews the recent updates on the thyroid and skin interplay, and it further discusses overt visible findings and various available treatment modalities.

Management of chronic urticaria in children: a clinical guideline

The aim of this guidance is to provide recommendations to clinicians and other interested parties on chronic urticaria in children. The Italian Society for Pediatrics (SIP), the Italian Society for Allergy and Immunology (SIAIP), the Italian Society for Pediatric dermatology (SIDerP) convened a multidisciplinary panel that prepared clinical guidelines for diagnosis and management of chronic urticaria in childhood. Key questions on epidemiology, natural history, diagnosis, and management were developed. The literature was systematically searched and evaluated, recommendations were rated and algorithms for diagnosis and treatment were developed. The recommendations focus on identification of diseases and comorbidities, strategies to recognize triggering factors, improvement of treatment by individualized care.

Real-world use of omalizumab in patients with chronic idiopathic/spontaneous urticaria in the United States

BACKGROUND

Omalizumab was approved for the treatment of chronic idiopathic urticaria (CIU)/chronic spontaneous urticaria (CSU) in the United States in March 2014.

OBJECTIVE

This study sought to describe real-world omalizumab use, in the United States, in a large cohort of patients with CIU/CSU.

METHODS

Patients with CIU/CSU (ages ≥12 years) initiated on omalizumab (index date) with ≥12 months of pre- and postindex data were identified in the an insurance claims data base (January 1, 2013, to July 31, 2016). Treatment patterns, including the dosing regimen and continuous use of omalizumab (no gaps for ≥60 days), were described during the 12-month postindex follow-up period.

RESULTS

A total of 1546 patients (mean ± standard deviation [SD] ages, 44 ± 14.5 years; 73.1% women) were identified. Most of the patients (84.5%) were initiated on omalizumab 300-mg dose; 90% maintained the initial dose, 7.5% had a dose increase, and 4.6% had a dose decrease. The mean ± SD omalizumab treatment duration was 9.1 ± 3.8 months, the mean ± SD number of omalizumab administrations was 8.3 ± 4.8, and the mean ± SD administration frequency was 44 ± 29 days. A proportion of the patients continuously treated with omalizumab for 6, 9, and 12 months was 67.3, 54.8, and 47.4%, respectively. Among the patients who discontinued omalizumab for ≥3 months (39.8%), 21% restarted the treatment after a mean ± SD of 4.4 ± 1.3 months. The proportion of patients who used other CIU/CSU-related medications decreased pre- to postindex (94.8 to 81.1%), with the highest decrease observed in oral corticosteroids (75.7 to 49.9%).

CONCLUSION

In this large real-world study, the majority of the patients with CIU/CSU were initiated on a 300-mg omalizumab dose and treated without titration up or down for 9 months on average. Most of the patients were continuously treated with omalizumab for ≥6 months, and one-fourth of the patients who discontinued treatment resumed it. Moreover, compared with baseline levels, the use of other CIU/CSU-related medications was lower after omalizumab initiation, with the most prominent decrease observed in oral corticosteroids.

Thyroid function and thyroid autoantibodies in patients with chronic spontaneous urticaria

Introduction

Chronic urticaria (CU) is a skin disease caused by autoantibodies against high affinity immunoglobulin E (IgE) receptor and against IgE. It is characterized by hives, erythematous wheals and redness present minimum twice a week for at least 6 weeks. It is observed that there is a strong association between CU and autoimmune diseases, such as autoimmune thyroiditis (AT).

Aim

To verify the frequency of AT in patients suffering from chronic spontaneous urticaria (CSU) and to confirm the coexistence of CU and AT in the Polish population.

Material and methods

One hundred and forty-eight patients with CSU were included to the study. The presence of anti-thyroperoxydase antibodies (anti-TPO) and anti-thyroglobulin antibodies (anti-Tg) was checked and thyrotropin (TSH), free thyroxine (fT4) and free triiodothyronine (fT3) concentration was measured. Results were compared with outcomes in a group of 35 patients with no history of skin disease.

Results

Thirty-three patients were diagnosed with AT. Frequency of elevated anti-TPO (p = 0.0045) and anti-Tg (p = 0.013) levels was much higher in patients with CU. A comparison of the current study and previous ones was conducted. In a group with CU, there was a higher risk of elevated anti-TPO (OR = 6.69) and anti-Tg (OR = 6.01) levels.

Conclusions

There is a statistically significant difference in the presence of AT between the patients with CU and the whole population. Doctors should consider examining patients with CU for AT. Adequate therapy and guidance for patients could be implemented at an early stage of thyroid disease and help induce remission of skin disorders.

Intestinal Epithelial Cell Endoplasmic Reticulum Stress and Inflammatory Bowel Disease Pathogenesis: An Update Review

The intestinal epithelial cells serve essential roles in maintaining intestinal homeostasis, which relies on appropriate endoplasmic reticulum (ER) function for proper protein folding, modification, and secretion. Exogenous or endogenous risk factors with an ability to disturb the ER function can impair the intestinal barrier function and activate inflammatory responses in the host. The last decade has witnessed considerable progress in the understanding of the functional role of ER stress and unfolded protein response (UPR) in the gut homeostasis and its significant contribution to the pathogenesis of inflammatory bowel disease (IBD). Herein, we review recent evidence supporting the viewpoint that deregulation of ER stress and UPR signaling in the intestinal epithelium, including the absorptive cells, Paneth cells, goblet cells, and enteroendocrine cells, mediates the action of genetic or environmental factors driving colitis in experimental animals and IBD patients. In addition, we highlight pharmacologic application of chaperones or small molecules that enhance protein folding and modification capacity or improve the function of the ER. These molecules represent potential therapeutic strategies in the prevention or treatment of IBD through restoring ER homeostasis in intestinal epithelial cells.

Fexofenadine Suppresses Delayed-Type Hypersensitivity in the Murine Model of Palladium Allergy

Palladium is frequently used in dental materials, and sometimes causes metal allergy. It has been suggested that the immune response by palladium-specific T cells may be responsible for the pathogenesis of delayed-type hypersensitivity in study of palladium allergic model mice. In the clinical setting, glucocorticoids and antihistamine drugs are commonly used for treatment of contact dermatitis. However, the precise mechanism of immune suppression in palladium allergy remains unknown. We investigated inhibition of the immune response in palladium allergic mice by administration of prednisolone as a glucocorticoid and fexofenadine hydrochloride as an antihistamine. Compared with glucocorticoids, fexofenadine hydrochloride significantly suppressed the number of T cells by interfering with the development of antigen-presenting cells from the sensitization phase. Our results suggest that antihistamine has a beneficial effect on the treatment of palladium allergy compared to glucocorticoids.

Positive CD63 Basophil Activation Tests Are Common in Children with Chronic Spontaneous Urticaria and Linked to High Disease Activity

BACKGROUND

The basophil activation test (BAT) using CD63 expression is a sensitive and specific tool for the diagnostic workup of autoimmune chronic spontaneous urticaria (CSU). The definition of a positive BAT is directly dependent on the reference range and the cutoff values established in control populations. As of now, the pediatric reference range and cutoff values of the CD63 BAT remain to be established.

METHODS

In this study, we analyzed CD63 expression in 80 children (1-17 years old) without chronic urticaria (i.e., controls) and compared the values to those of a pediatric cohort of 105 CSU patients and 23 physical urticaria (PU) patients.

RESULTS

Based on the log-normal distribution of CD63 values in control subjects, the reference range and the cutoff for positive CD63 BAT values was established to be 1.2-1.8% (95% CI) and 1.8%, respectively. Children with CSU showed significantly elevated and significantly increased BAT values compared to healthy controls (Wilcoxon rank test p value <0.001). In contrast, no difference was found between BAT results in controls and PU patients. In pediatric CSU patients, a higher disease activity was associated with higher BAT values.

CONCLUSIONS

Our study provides, for the first time, reference and cutoff values for the CD63 BAT in children. Our findings show that positive CD63 BAT are common in children with CSU and linked to a high disease activity.

Effects of Helicobacter pylori Eradication in Chronic Spontaneous Urticaria: Results from a Retrospective Cohort Study

BACKGROUND AND OBJECTIVE

Helicobacter pylori (Hp) infection has been hypothesised to play a major role in the pathogenesis of chronic spontaneous urticaria (CSU). Despite only weak evidence from Hp eradication studies, screening for Hp infection is still recommended in several CSU guidelines. The aim of this study was to investigate the effect of Hp eradication in combination with standard CSU treatment in Hp-positive compared with Hp-negative patients, applying the latest guidelines for both diseases.

METHODS

138 consecutive patients with CSU were enrolled in this retrospective cohort study. All patients underwent gastroscopy and Hp status was determined by urease testing and histologic examination. Seventy-five patients were diagnosed as Hp negative and 47 patients fulfilled criteria for definite Hp infection, 45 of whom received eradication therapy. Sixteen patients who received eradication therapy without an appropriate indication served as the medication control. All patients received symptomatic treatment with antihistamines and/or glucocorticoids regardless of Hp status. Partial response (PR) was defined as subjective amelioration of CSU symptoms; patients returning for further CSU treatment within 6 months were considered non-responders/relapsers (NRs).

RESULTS

The prevalence of Hp infection was comparable with Hp seroprevalence data reported for healthy western populations. Standard treatment of CSU led to relief of symptoms independent of Hp status. Hp eradication by standard triple therapy had no additional effect on PR (p = 0.32) or NR (p = 0.50).

CONCLUSIONS

Hp eradication has no discernible effect on CSU beyond that of standard CSU therapy. Therefore, Hp eradication should only be initiated in accordance with currently accepted indications of Hp treatment guidelines.

Role of nidi of infection in various skin diseases

Reviewed scientific publications that define the location of foci of chronic infections in dermatology. Indicated by the currently existing problematic issues and their solutions.

The use of biologicals in cutaneous allergies - present and future

PURPOSE OF REVIEW

Up-to-date biologicals in cutaneous allergies play - unfortunately - only a minor role. However, this situation might change. Recently, omalizumab was licensed for chronic urticaria; this article reviews recent advances in the use of biologicals in cutaneous allergies.

RECENT FINDINGS

Interestingly, the mechanism of omalizumab appears to be different in urticaria and allergic asthma for which the drug has been licensed previously. In urticaria dosage is not dependent on serum IgE-levels and response is seen very often after only 12 h. Other indications in cutaneous allergy in which biologicals have been investigated, at least in case reports or small studies, are TNF-α-antagonists and rituximab in chronic urticaria, omalizumab, rituximab and TNF-α-antagonists in atopic dermatitis as well as mepolizumab in this disease. However, all these studies appear to show a benefit for individual patients but not a clear breakthrough for the whole group of patients involved. This, however, might also be one of the future approaches that sub-groups of patients who have different responses to biologicals may be identified, as apparently different cytokine patterns are predominantly involved in the individual patient.

SUMMARY

In conclusion, although currently only one biological is approved in chronic urticaria, there is hope that a rapid better understanding of individual disease factors will support the development of other novel drugs in this field.

Fexofenadine regulates nuclear factor-κB signaling and endoplasmic reticulum stress in intestinal epithelial cells and ameliorates acute and chronic colitis in mice

The aim of this study was to evaluate the effect of fexofenadine on intestinal inflammation. HCT116 and COLO205 cells were pretreated with fexofenadine and then stimulated with tumor necrosis factor (TNF)-α. Interleukin (IL)-8 expression was determined by real-time reverse-transcription polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay. DNA-binding activity of nuclear factor-κB was assessed by electrophoretic mobility shift assay. The molecular markers of endoplasmic reticulum (ER) stress were evaluated by Western blot analysis and PCR. In the acute colitis model, mice were given 4% dextran sulfate sodium (DSS) for 5 days with or without fexofenadine. IL-10(-/-) mice were used to evaluate the effect of fexofenadine on chronic colitis. Fexofenadine significantly inhibited the upregulated expression of IL-8 in HCT116 and COLO205 cells stimulated with TNF-α. Fexofenadine suppressed nuclear factor-κB DNA-binding activity. C/EBP homologous protein mRNA expression was enhanced in the presence of TNF-α, and it was dampened by pretreatment of fexofenadine. In addition, the induction of ER stress markers caspase-12 and p-eukaryotic initiation factor 2 (eIF2)-α was significantly suppressed by the pretreatment of fexofenadine. Administration of fexofenadine significantly reduced the severity of DSS-induced murine colitis, as assessed by the disease activity index, colon length, and histology. In addition, the DSS-induced phospho-IκB kinase activation was significantly decreased in fexofenadine-pretreated mice. Finally, fexofenadine significantly reduced the severity of colitis and the immunoreactivity of caspase-12 and p-eIF2-α in IL-10(-/-) mice as compared with controls. These results suggest that fexofenadine is a potential therapeutic agent for the treatment of inflammatory bowel disease.

Pathogenic intracellular and autoimmune mechanisms in urticaria and angioedema

Urticaria and angioedema are common disorders. Chronic urticaria is defined as lasting longer than 6 weeks. Causes of chronic urticaria fall into the following categories: physical, allergic, hereditary, autoimmune, and idiopathic. Basophils and mast cells are the primary effector cells responsible for clinical symptoms and signs. These cells produce and secrete a variety of mediators including histamine, leukotrienes, prostaglandins, cytokines, chemokines, and other pro-inflammatory mediators. This leads to vasodilation, fluid exudation, increased vascular permeability, and accumulation of additional secondary inflammatory cells. Two mechanisms have been investigated as possibly contributing to the pathogenesis of chronic urticaria. One is the development of autoantibodies to FcεRI or IgE on mast cells and basophils. This appears to be responsible for 30-50 % of cases. The other is dysregulation of intracellular signaling pathways involving Syk, SHIP-1, or SHIP-2 in basophils and mast cells. The primary treatment for chronic urticaria is to treat the underlying pathology, if any can be identified. Otherwise, in idiopathic cases, H1 antihistamines, H2 antihistamines, antileukotrienes, and corticosteroids constitute the main pharmacologic treatment modalities. In severe and recalcitrant cases of chronic and autoimmune urticaria, immunosuppressive drugs have been used, most commonly cyclosporin. More recent experimental studies have also suggested that omalizumab, an anti-IgE therapy, may be of benefit. Currently, inhibitors of Syk are also being developed and tested in the laboratory and in animal models. As our understanding of the pathogenesis of idiopathic urticaria increases, development of additional drugs targeting these pathways may provide relief for the significant physical and psychological morbidity experienced by patients with this disorder.

Multiple nonsteroidal anti-inflammatory drug-induced cutaneous disease: what differentiates patients with and without underlying chronic spontaneous urticaria?

BACKGROUND

Multiple nonsteroidal anti-inflammatory drug (NSAID) cutaneous reactors may be otherwise normal or have underlying chronic spontaneous urticaria (CSU). This study compared these two phenotypes of NSAID-hypersensitive subjects.

METHODS

A total of 97 multiple NSAID reactors underwent oral challenges with paracetamol, etoricoxib and tramadol. Atopic status was investigated in all patients, and autoreactivity was ascertained in some cases as well. Otherwise normal multiple NSAID reactors were reevaluated after 1-5 years in order to detect their proneness to CSU.

RESULTS

At the first visit, 41 patients had CSU and 56 had multiple NSAID intolerance without any underlying cutaneous disease. Altogether, 22, 10 and 6% of patients did not tolerate paracetamol, etoricoxib and tramadol, respectively, on oral challenge. Intolerance to these alternative drugs showed a strong association (p < 0.01 with all combinations). The two subgroups of patients did not show any difference in terms of mean age, gender distribution, prevalence of atopic diseases, prevalence of single offending NSAIDs and prevalence of intolerance to paracetamol, etoricoxib or tramadol on oral challenge. In all, 20% of multiple NSAID reactors without CSU at presentation developed CSU between 6 months and 5 years after the initial clinical evaluation.

CONCLUSIONS

Multiple NSAID cutaneous reactors with or without CSU seem identical from a clinical point of view, and some of the latter group show a propensity to acquire the former phenotype over time. A subset of patients apparently identical to the general population of multiple NSAID reactors also react to drugs exerting little or no cyclooxygenase-1 enzyme inhibition and might represent a distinct phenotype of NSAID-hypersensitive patients possibly characterized by a different underlying pathogenesis.

Treatment of refractory chronic urticaria: current and future therapeutic options

Chronic urticaria is a distressing disease that affects up to 1 % of the general population at a time point in life and may severely worsen the quality of life. First-line treatment has been based on antihistamines, and presently relies on the use of non-sedating, second-generation antihistamines; following the recommendations of the recent international guidelines, in patients who do not respond to antihistamines at licensed doses, the daily dosage of these drugs can be increased up to fourfold. Nonetheless, a significant proportion of patients with chronic urticaria remain poorly controlled; in these cases, alternative therapeutic approaches have to be considered. This article critically reviews all of the third- and fourth-line treatment options suggested for patients whose disease is refractory to antihistamines, including systemic corticosteroids, leukotriene receptor antagonists, several different anti-inflammatory drugs (dapsone, sulfasalazine, hydroxychloroquine), various immunosuppressive drugs (calcineurin inhibitors, methotrexate, cyclophosphamide, azathioprine, mycophenolate mofetil), intravenous immunoglobulin, and newer treatment options, such as omalizumab and other biologic drugs. In addition, the article examines possible future treatment options based on recent findings about pathogenic mechanisms, and considers the treatment of antihistamine-unresponsive urticaria in special conditions such as children and pregnancy/lactation. The evidence supporting the use of several of the discussed drugs is presently limited and thus insufficient to recommend their routine use; as a consequence, such compounds should be considered only in specific cases and in adequate settings.

Mechanisms of Hypersensitivity

Allergic reactions to drugs are not always the result of the drug’s protein-binding capacity, biotransformation, or degradation. Mediator release may occur via cross-linking of cell-bound IgE by di-(multi-) valent free drug. Physiological and pharmacological effects of histamine are mediated through four receptors, H₁, H₂, H₃, and H_4. The H₃ receptor has a regulatory role in the release of neurotransmitters such as serotonin and dopamine; the H₄ receptor exerts a chemotactic effect on several cell types associated with allergy and asthma. Cysteinyl leukotrienes and PAF are powerful mediators of anaphylaxis, asthma, and shock. Sphingosine-1-phosphate, elevated in the lungs of asthmatics, regulates pulmonary epithelium permeability and contributes to the pathogenesis of anaphylaxis. Urticaria is a heterogeneous disease with many subtypes. Both ACE inhibitors and angiotensin II receptor blockers may cause angioedema. Abacavir changes the shape of the HLA antigen-binding cleft producing an alteration in the repertoire of self-peptides that bind HLA-B*57:01 and a T cell response to self-proteins. Drug-induced delayed-type cutaneous hypersensitivity reactions are mediated by CD4+ and CD8+ CD3+ T cells in the dermis and epidermis. Granulysin appears to be a key molecule for keratinocyte killing in TEN/SJS. Drugs provide good examples of types II (immune hemolytic anemia, drug-induced thrombocytopenia) and III (serum sickness-like) hypersensitivities.

The role of focal infections in the pathogenesis of psoriasis and chronic urticaria

INTRODUCTION

The Focal Infection Theory, originally presented at the beginning of the 20(th) century, postulates that systemic diseases can be caused by microorganisms that arise from the focus of infection. Foci of infections have been described as sinuses, adenoids, tonsils, teeth, genitourinary tract, gall bladder and kidneys. A focus of infection is defined as the area that can occur in any part of the body, contains a pathogen (microorganism) and is usually asymptomatic. There are discordant opinions about the role of focal infections in the pathogenesis of psoriasis and urticaria.

AIM

To establish whether there is a higher incidence of focal infections in patients with chronic urticaria and psoriasis.

MATERIAL AND METHODS

We retrospectively reviewed 129 patients with a history of psoriasis and chronic urticaria: 58 women and 71 men treated in the Department of Dermatology of the Jagiellonian University Medical College in Krakow.

RESULTS

In the analyzed group, 11 patients had a dental consultation, 58 - laryngological consultation and 29 women had a gynecological consultation. The most common examples of focal infection were tonsillitis, upper respiratory tract infections, sinusitis, dental caries and genitourinary tract infections. Aggravating factors were similar to previously described.

CONCLUSIONS

A high incidence of focal infections in patients with psoriasis and urticaria suggests that infections may play a significant role in the pathogenesis of these skin disorders. Treatment of infection foci may play the key role in the remission of skin changes.

Chronic spontaneous urticaria: an autoimmune disease? A revision of the literature

The cause of chronic spontaneous urticaria has been an enigma for decades, but the recognition of functional autoantibodies in some patients with the spontaneous chronic urticaria has opened up a new concept of autoimmune urticaria. Clinical and laboratory features are in keeping with an autoimmune aetiology for many patients with otherwise inexplicable disease, but there is still debate about the importance of functional autoantibodies in the disease pathogenesis, how to test them and the clinical implications for treatment and prognosis. This review will look at the evidence for there being an autoimmune subset of urticaria, the strengths and weaknesses of the available tests in current use.

Urticaria and angioedema

Urticaria and angioedema are common disorders that can severely impair the quality of a patient's life and can be extremely difficult to treat. Symptoms can persist for years to decades. The causes of urticaria and angioedema are varied and may be immunologic, nonimmunologic, or idiopathic. This article reviews the literature and provides primary care physicians with up-to-date information of the epidemiology, basic pathophysiology, diagnosis, and management of this common and often debilitating condition. Additionally, clinical manifestations of acute and chronic urticaria, hereditary and acquired angioedema, as well as the physical urticarias will be discussed.

Urticaria and its subtypes: the role of second-generation antihistamines

Urticaria is a heterogeneous group of debilitating skin disorders characterized by wheals, pruritus, and frequently angioedema. The various forms of urticaria are often chronic and can exact a toll on quality of life. New diagnostic criteria and management guidelines are available to assist primary care physicians in the identification and proper treatment of different subtypes of urticaria. Second-generation antihistamines are recommended as first-line therapy because of their high degree of efficacy and safety. It is important to note, however, that European indications for most agents in this class are limited to specific forms of urticaria. The exception is desloratadine, the only second-generation antihistamine approved for the treatment of all urticaria subtypes in the European Union. Guidelines and best practice suggest that doses of antihistamines up to 4 times higher than those normally recommended for urticaria may benefit patients who do not respond to standard doses of antihistamines. Adjunctive therapy with leukotriene receptor antagonists may be advantageous in certain subgroups of patients who have suboptimal responses to antihistamine monotherapy. In all cases, physicians should work closely with patients to ensure proper adherence to prescribed regimens-a component that is often lacking but holds the key to successful outcomes.

Evidence-based evaluation and management of chronic urticaria in children

Urticaria affects nearly 25% of the population at some time in their lives. In a subset of children, urticaria will develop into a chronic condition that can greatly affect quality of life. Although numerous causes and triggers are proposed for chronic urticaria (CU) in children, ranging from infections, allergens, and medications to physical factors and autoimmune disease, the exact etiology is not always identifiable. Accordingly, a large subset of cases are designated "chronic idiopathic urticaria." Because of the clinical complexities of CU, as well as the confusing literature on this topic, we have developed a conceptual framework based on the cumulative evidence to assist with the categorization, clinical evaluation, and treatment of CU in children.

Chronic urticaria: a comparison of management guidelines

INTRODUCTION

Chronic urticaria is characterized by recurring episodes of spontaneous transient dermal wheals and pruritus, with or without angioedema, which can persist for ≥ 6 weeks. Chronic urticaria impairs quality of life, emphasizing the need for effective treatments. Professional societies and clinical experts have issued evidence-based recommendations for the management of chronic urticaria, including recommending the use of second-generation antihistamines as a first-line therapy.

AREAS COVERED

A Medline search was conducted from 2000 to 2011 using the following terms, alone or in combination: 'chronic urticaria', 'management guidelines', 'consensus guidelines' and 'expert opinions'. Ten management guidelines/expert opinions met the inclusion criteria.

EXPERT OPINION

There was a universal agreement among the articles reviewed, that low-sedating, second-generation antihistamines should be prescribed as a first-line treatment of chronic urticaria. For refractory urticaria, however, recommendations varied and included dose escalation of second-generation antihistamines and adjunctive treatments with other agents of the same class, such as sedating antihistamines or leukotriene receptor antagonists. More research into effective second-line treatments and consistent implementation of current guidelines is needed, to ensure that treatment is based on clinical evidence.

Efficacy of Tripterygium hypoglaucum Hutch in adults with chronic urticaria

OBJECTIVES

The study objectives were to evaluate the efficacy and safety of Tripterygium hypoglaucum Hutch (THH) in adult with severe chronic urticaria (CU) by performing a randomized, double-blind, placebo-controlled clinical trial.

METHODS

Seventy-eight (78) adult patients with severe CU, 21-58 years of age, responding poorly to antihistamines alone, were randomly divided into two groups: the therapeutic group with THH 3 tablets 3 times daily (n = 40) and the control group with placebo 3 tablets 3 times daily (n = 38). Meanwhile, all patients jointly received cetirizine hydrochloride (HCl) 10 mg once daily throughout the study period. The efficacy of THH was assessed by the scoring system of 4-point scale and the subject's global assessment of relief.

RESULTS

Sixty-nine (69) of 78 patients (37 in the therapeutic group, 32 in the control group) completed the study. By the end of the fourth week, there was a 67% improvement of total effective rate (TER) with THH compared with a 28% improvement with placebo by per-protocol analysis (χ(2) = 10.68, p = 0.0011), while by intention-to-treat analysis, 63% and 24% improvements of TER were respectively observed in the therapeutic group and the control group (χ(2) = 11.36, p = 0.001). THH with cetirizine showed statistical superiority to placebo with cetirizine during each study week for changes in total severity scores (p ≤ 0.001). In weekly analyses, THH was also statistically superior to placebo in reducing the mean pruritus scores during each study week (p ≤ 0.005).

CONCLUSIONS

This study shows that the therapeutic effect of THH with cetirizine is predominant over that of cetirizine alone in adult CU. THH with cetirizine may play an important role in the therapy of CU and be a useful treatment for CU.

Chronic spontaneous urticaria in children: itching for insight

While there is increasing information about the pathogenesis and treatment of chronic spontaneous urticaria (csU) in adults, there is little published information about csU in children. Consequently, most of the recommendations contained in current guidelines for the prevention and treatment of csU in infants and children is based on extrapolation of data obtained in adults. To rectify this, this review points out critical gaps in our knowledge and suggests strategies which may help us to improve our understanding of this condition. How common is csU in children? What do we know about its clinical presentation and the presence of useful biomarkers? What are its common underlying causes? What is the course of csU in children? How does csU affect the everyday life of children? What treatment options are available for children? To answer these questions, two separate types of information are required. The first is information about the prevalence of the condition in the community at large and how csU affects the everyday life of both the child-patient and the parent or carer. Because most csU cases in infants and children do not come to specialists but are treated by general practitioners or by parents using over-the-counter medications, these questions may be answered only by general population surveys or schools programmes. The second is clinical information including family history and disease presentation, the presence of biomarkers and comorbidities, objective measures of severity, frequency and duration of exacerbations, the response to therapy and the time to remission. Targeted questionnaires need to be developed and validated for these investigations. This has already begun in Germany with the establishment of the CU-KID Netzwerk (Email address: cu-kid@charite.de), the aim of which is to identify clinical centres and colleagues who treat children with urticaria and to initiate the information gathering described above.

Activation of blood coagulation in autoimmune skin disorders

The immune system and blood coagulation are simultaneously activated in several inflammatory systemic disorders, such as lupus erythematosus, rheumatoid arthritis and inflammatory bowel diseases. Proinflammatory cytokines, such as IL-6 and TNF-alpha, induce the expression of tissue factor, the main initiator of blood coagulation. Activated proteases of coagulation in turn act on protease-activated receptors, inducing the expression of various proinflammatory cytokines. This cross-talk between inflammation and coagulation amplifies and maintains the activation of both systems. This review focuses on three skin disorders: chronic urticaria (CU), which is considered autoimmune in approximately 50% of cases, bullous pemphigoid (BP), which is the prototype of autoimmune blistering disease, and psoriasis, which is an immune-mediated dermatitis. In CU, the activation of coagulation, which is due to the involvement of eosinophils and tissue factor pathways with the generation of thrombin, has local implications by increasing dermal vascular permeability. Preliminary data indicate that anticoagulant treatment with heparin and warfarin may be effective in reducing the symptoms of this disorder. In BP, the activation of coagulation seems to have both local and systemic implications. Locally, eosinophils and thrombin participate in bulla formation and tissue damage; systemically, the activation of coagulation may explain the increased thrombotic risk observed in these patients. In psoriasis, the activation of coagulation seems to be mainly systemic, potentially contributing to the increased cardiovascular risk associated with this disease.

Skin autoimmunity and blood coagulation

Evidence exists that the immune and coagulation systems are simultaneously activated in some systemic autoimmune disorders. Although proinflammatory mediators induce tissue factor (TF) expression, the main initiator of blood coagulation, activated proteases of coagulation may act on protease-activated receptors (PAR) triggering inflammation. Such a cross-talk amplifies and maintains the activation of both systems. This review focuses on the involvement of immune and coagulation system in two skin disorders as chronic urticaria (CU), autoimmune in about 45% of cases, and bullous pemphigoid (BP), the prototype of autoimmune blistering diseases. Several investigators demonstrated the activation of coagulation in CU through the involvement of eosinophils, of TF pathway with thrombin generation and increased vascular permeability. Preliminary data indicate that anticoagulant treatment with heparin and warfarin may be effective in reducing the symptoms of this disorder. The activation of coagulation seems to display local and systemic implications in BP. Eosinophils' recruitment and thrombin generation locally contribute to the bulla formation and tissue damage. The systemic activation of coagulation may explain the increased thrombotic risk observed in these patients. Taken together, these data provide the rationale for proposing clinical trials on the anticoagulant treatment in both CU and BP patients.

Identification of the etiologies of chronic urticaria in children: a prospective study of 94 patients

The etiologies of chronic urticaria (CU) in childhood remains incompletely understood because of limited data in children. The objective of this study was to examine some of the possible etiologies of CU in children by focusing on the functional autoantibody to FcepsilonRIalpha and IgE, thyroid autoimmunity, urticarial vasculitis, parasitic infestation and food allergy. Children 4-15 yr of age with CU were investigated for complete blood count, erythrocyte sedimentation rate (ESR), antinuclear antibody (ANA), CH(50), free-T4 (FT(4)), thyroid stimulating hormone (TSH), anti-thyroglobulin and anti-microsomal antibody, autologous serum skin test (ASST), skin prick tests (SPT) for foods, food challenges, and stool examination for parasites. Ninety-four children who met the criteria for CU were recruited. Patients with physical urticaria were excluded. Eosinophilia and elevated ESR were found in 23% and 13%, respectively. High ANA titers were found in 2%. None of these patients had clinical features of urticarial vasculitis, abnormal CH(50) level, abnormal TSH and FT(4). Anti-thyroglobulin and anti-microsomal antibodies were not detected. Positive ASST was found in 38%. There were no differences in medication requirement and CU remission between patients with positive and negative ASST. Parasites were found in 5% without clinical correlation. SPT to foods was positive in 35%. Positive food challenges were found in six/nine patients with positive history of food allergy and two/seven patients with negative history. Food avoidance was beneficial to the subgroup of patients with positive history of food allergy only.