Urticaria and angioedema: a clinical spectrum

Diffusive mediator feedbacks control the health-to-disease transition of skin inflammation

The spatiotemporal dynamics of inflammation provide vital insights into the understanding of skin inflammation. Skin inflammation primarily depends on the regulatory feedback between pro- and anti-inflammatory mediators. Healthy skin exhibits fading erythema. In contrast, diseased skin exhibits expanding erythema with diverse patterns, which are clinically classified into five types: circular, annular, arcuate, gyrate, and polycyclic. Inflammatory diseases with expanding erythema are speculated to result from the overproduction of pro-inflammatory mediators. However, the mechanism by which feedback selectively drives the transition from a healthy fading erythema to each of the five types of diseased expanding erythema remains unclear. This study theoretically elucidates the imbalanced production between pro- and anti-inflammatory mediators and prospective treatment strategies for each expanding pattern. Our literature survey showed that eleven diseases exhibit some of the five expanding erythema, thereby suggesting a common spatiotemporal regulation underlying different patterns and diseases. Accordingly, a reaction-diffusion model incorporating mediator feedback reproduced the five observed types of diseased expanding and healthy fading patterns. Importantly, the fading pattern transitioned to the arcuate, gyrate, and polycyclic patterns when the productions of anti-inflammatory and pro-inflammatory mediators were lower and higher, respectively than in the healthy condition. Further depletion of anti-inflammatory mediators caused a circular pattern, whereas further overproduction of pro-inflammatory mediators caused an annular pattern. Mechanistically, the bistability due to stabilization of the diseased state exhibits circular and annular patterns, whereas the excitability exhibits the gyrate, polycyclic, arcuate, and fading patterns as the threshold of pro-inflammatory mediator concentration relative to the healthy state increases. These dynamic regulations of diffusive mediator feedback provide effective treatment strategies for mediator production wherein skins recover from each expanding pattern toward a fading pattern. Thus, these strategies can estimate disease severity and risk based on erythema patterns, paving the way for developing noninvasive and personalized treatments for inflammatory skin diseases.

Allergic Dermatoses

The purpose of this article is to review the current available material pertaining to atopic dermatitis, contact dermatitis, urticaria, and angioedema. This article focuses on each disease process's clinical presentation, diagnosis, and management. Although atopic dermatitis and contact dermatitis are similar, their development is different and can affect a patient's quality of life. Urticaria and angioedema are also similar, but the differentiation of the two processes is crucial in that they have significant morbidity and mortality, each with a different prognosis.

Skin Biopsy, the Allergists' Tool: How to Interpret a Report

Inflammatory dermatoses are frequently encountered by the allergist, and histologic evaluation achieved through skin biopsy can be of tremendous value clinically. There is no substitute for a thorough history and physical exam; however, the skin biopsy is a simple, in-office procedure with little risk of complication that can provide invaluable information when a diagnosis is uncertain. Histopathologically, many inflammatory eruptions can look similar or overlap, but information provided by the dermatopathologist can help the clinician render or refine the clinical diagnosis and guide management. This review will discuss descriptive elements contained in the pathology report to provide a framework that can be used by the allergist to comfortably and confidently diagnose inflammatory dermatologic conditions.

Clinical evaluation and treatment of chronic urticaria

Chronic urticaria is a common disease characterized by recurrent pruritic wheals with surrounding erythema for >6 weeks. It is associated with a significant health care burden and affects patient quality of life. The etiology of chronic urticaria is often difficult to elucidate; however, known etiologies include autoimmune urticaria, physical urticarias (eg, cold, cholinergic, and delayed pressure urticaria), and idiopathic urticaria. The etiology is unknown in many patients, leading to a diagnosis of chronic idiopathic urticaria. The diagnosis of chronic idiopathic urticaria can be challenging for the primary care physician because of the disease's chronic symptoms. Diagnosis requires a detailed patient history and comprehensive physical examination, with additional testing tailored to the patient's history. Effective treatments include antihistamines, leukotriene receptor antagonists in combination with antihistamines, and oral immunomodulatory drugs, including corticosteroids, cyclosporine, dapsone, hydroxychloroquine, and sulfasalazine. Newer experimental therapies include intravenous immunoglobulin and omalizumab. This article reviews the pathophysiology, diagnosis, and treatment of chronic urticaria.

Allergy and the skin

Allergic skin disorders include urticaria, angioedema, contact dermatitis and atopic dermatitis, but the model fitting most closely the systemic concept of allergy is atopic dermatitis (AD), the pathogenesis of which is linked to a complex interaction between skin barrier dysfunction and environmental factors such as allergens and microbes. In particular, an important advance was the demonstration that the mutation of the skin barrier protein filaggrin is related strictly to allergen sensitization and to the development of asthma in subjects with AD. The altered skin barrier function, caused by several factors, results in the passage of allergens through the skin and to systemic responses. A pivotal role in such a response is exerted by Langerhans cells which, via their immunoglobulin E (IgE) receptor, capture the allergens and present them to T cells. When T helper type 2 (Th2) cells are activated, the production of a proinflammatory cytokines and chemokines pattern sustains the persistence of inflammation. Known AD-related cytokines are interleukin (IL)-5, IL-13 and tumour necrosis factor (TNF)-alpha, with emerging importance for IL-17, which seems to drive airway inflammation following cutaneous exposure to antigens, and IL-31, which is expressed primarily in skin-homing Th2 cells. Skin-homing is another crucial event in AD, mediated by the cutaneous lymphocyte-associated antigens (CLA) receptor, which characterizes T cell subpopulations with different roles in AD and asthma.

Urticaria unresponsive to antihistaminic treatment: an open study of therapeutic options based on histopathologic features

BACKGROUND

The non- or low-sedating H1 receptor antagonists represent the basic therapy for urticaria.

OBJECTIVE

To test an alternative approach to patients unresponsive to conventional treatment.

MATERIALS AND METHODS

A total of 22 patients with chronic urticaria unresponsive to conventional antihistamine treatment were enrolled for this study. They had uncontrolled urticaria even using multiple combinations of antihistamines on maximum doses and corticosteroids in short cycles (prednisone 20-40 mg, per os once a day, 3-7 days per month). Cutaneous biopsies of the urticaria lesions were taken. These findings were classified as: (I) a mixture of perivascular dermal inflammatory infiltrate composed of lymphocytes, monocytes and neutrophils and/or eosinophils; (II) inflammatory infiltrate composed chiefly of neutrophils; and (III) inflammatory infiltrate composed mainly of eosinophils. According to histology, the patients were submitted to one of the following therapeutic schemes: class A - antihistamine treatment plus dapsone; class B - colchicine or dapsone; class C - montelukast.

RESULTS

Four patients in class A, 08 in class B and seven in class C displayed complete control of urticaria after 12 weeks of treatment; one patient in class B and two in class C did not respond to treatment. Two years after discontinuation, 16 patients are still free of urticaria.

CONCLUSIONS

This study suggests an alternative approach for treating unresponsive chronic urticaria.

Other Allergic Skin Disorders

In this chapter we discuss allergic skin disorders other than atopic dermatitis (AD): the urticaria-angioedema syndrome, allergic contact dermatitis (ACD), protein contact dermatitis (PCD), phytodermatitis, allergic photodermatitis and allergic vasculitis.

Sociodemographic and clinical characteristics, causal factors and evolution of a group of patients with chronic urticaria-angioedema

CONTEXT AND OBJECTIVE

Chronic urticaria-angioedema is a common, multiple-cause complaint. The aim was to investigate the sociodemographic and clinical characteristics, causal and aggravating factors and evolution of urticaria-angioedema.

DESIGN AND SETTING

This was a descriptive prospective study carried out at the Dermatology outpatient clinic of Faculdade de Medicina de Botucatu, Universidade Estadual Paulista (Unesp).

METHODS

A total of 125 patients with chronic urticaria-angioedema were evaluated to obtain sociodemographic data, anamnesis, dermatological and general clinical data and laboratory data, emphasizing causal and aggravating factors and complaint evolution.

RESULTS

Chronic urticaria-angioedema occurred mainly in females (mean age: 35 years), but also in men (mean age: 32 years). White color and living in urban areas also predominated. There was no preferential time for symptoms to appear, and nighttime was the most commonly reported time for clinical worsening. Around half of the patients had urticaria associated with angioedema. There were no associated factors in most of the cases, and stress was the most commonly reported aggravating factor. The cause was ascertained in 37.6% of our cases. The mean duration of follow-up was 11.7 months. Around 60% of the patients evolved with the problem under control, 32% improved, 9% had no change in dermatological condition and only one patient worsened.

CONCLUSIONS

Chronic urticaria-angioedema was more common among middle-aged women. It is a long-term disease, and its cause was explained in about one-third of the patients. Half of the patients presented disease control after treatment lasting an average of approximately one year.

Urticaria and angioedema

Urticaria and angioedema are commonly encountered complaints in children. Although the diagnosis is clear, establishing an etiology, especially with respect to chronic urticaria, can be challenging. A significant proportion of chronic urticarial cases are now considered to have an autoimmune etiology. This article reviews progress in the field of urticaria and angioedema including developments in pathogenesis, description of laboratory testing, and review of medications. Urticaria and angioedema can usually be controlled by avoidance of triggers, a variety of supportive medications, and reassurance.

Pruritic dermatoses: overview of etiology and therapy

This review begins with a brief survey of the neurophysiology and neuroanatomy of pruritus, and goes on to describe the etiology of the major allergic and nonallergic pruritic disorders. The etiology of pruritus often suggests the appropriate treatment. For example, urticaria, which is primarily mediated by histamine, is amenable to treatment with H1 antihistamines. Second-generation, nonsedating antihistamines appear to be more effective than sedating antihistamines, perhaps because of better compliance. Other systemic pharmacologic options may be useful in nonhistamine-mediated disorders, for example, immunomodulators for inflammation-induced pruritus or opiate antagonists for atopic dermatitis. Nonpharmacologic measures, such as proper skin care, and physical modalities, such as phototherapy or acupuncture, may also be helpful.

Helicobacter pylori infection in skin diseases: a critical appraisal

More than 50% of the human population have long-term Helicobacter pylori infection, causing, in some cases, severe diseases such as peptic ulcers and stomach cancer. In the last few years several extra-gastrointestinal disorders have been associated with H. pylori infection. This review summarized the current medical literature, identified through hand searching and MEDLINE research, including our own studies, with regard to H. pylori and skin diseases. From the literature it can be seen that the role of H. pylori in skin diseases is still a controversial subject. Randomized controlled trials with adequate masking and sample sizes are still lacking. The best evidence comes from studies investigating chronic urticaria in which chronic urticaria disappeared in many patients with H. pylori infection after careful eradication of the H. pylori. Moreover, there are promising recent reports of beneficial H. pylori eradication in Behçet's disease, pruritus cutaneus, prurigo chronica, prurigo nodularis and in some patients with lichen planus, but not in rosacea or psoriasis. Before any conclusions with respect to other skin diseases such as atopic dermatitis, Schoenlein-Henoch Purpura, Sweet's syndrome, Sjögren syndrome or systemic sclerosis may be drawn, additional randomized, double-blinded and placebo-controlled studies including adequate diagnostic schedules, sufficient eradication treatment protocols, confirmation of eradication and adequate control groups are needed. The cutaneous pathology of H. pylori is far from being clear, but it is speculated that the systemic effects may involve increased mucosal permeability to alimentary antigens, immunomodulation, an autoimmune mechanism or the impairment of vascular integrity.

Chronic urticaria: background, evaluation, and treatment

Urticaria and angioedema will affect 15% of the general population during their lifetime, and this remains one of the most vexing cutaneous conditions to evaluate and treat. Patients frequently go from one physician to another in hopes of finding a healthcare provider who can identify the cause and cure the ailment. Physicians treating hives are equally frustrated as they ponder the utility of obtaining a panel of screening laboratory tests that have previously been shown to have a low yield or obtaining selected allergy tests in a group of patients who are no more prone to allergic disease than the general public. This review presents recent information in a clinical context with the aim of aiding the physician in understanding the pathophysiology of urticaria and formulating an intelligent evaluation and treatment plan.

Cyclosporin A in patients affected by chronic idiopathic urticaria: a therapeutic alternative

Chronic Idiopathic Urticaria (CIU) is a cutaneous disorder for which there is no identifiable specific etiologic agent. Some recent evidences suggest that CIU might be an autoimmune disease. We analyzed immunological features occurring in CIU and evaluated effectiveness and tolerance of Cyclosporin A (CsA) treatment in patients unresponsive to antihistaminic treatment. Twenty patients with CIU were recruited after a selective diagnostic protocol and were divided into two groups. CsA was prescribed for group 1 and Prednisone for group 2 as control, for 8 weeks. Before and after the therapy we performed on all patients immunological studies. For all patients symptoms disappeared after a few days of therapy. Before therapy all patients showed activated B cells (CD19+CD23+ cells) and among B CD19+ cells, about 20% were CD5+ (cells that synthesize natural autoantibodies). After treatment with Prednisone in group 2, a significant reduction of CD4+ lymphocytes (p = 0,01) was observed. Our findings might support the CIU autoimmune pathogenetic hypothesis. The clinical remission in the CsA-treated group confirmed the therapeutic effectiveness of this therapy in antihistaminic unresponsive CIU and, at dosage used, side effects were rare, mild and reversible. Thus, CsA might be a good therapeutic alternative in CIU patients unresponsive to conventional treatments.

Mast cell activation in acquired chronic urticaria-angioedema

Mast cells play a central role in the pathogenesis of many allergic disorders. They can be activated in different ways. The present study was focused to evaluate the role of mast cells in acquired chronic urticaria-angioedema induced by gastroesophageal reflux. Tryptase, an important marker of mast cell activation, was detected with UniCap Tryptase Fluoroenzymeimmunoassay (Pharmacia & Upjohn AB, Uppsala, Sweden). Eight subjects were studied: four males and four females, aged between 29 and 71 years (mean age: 45 yrs.), suffering from acquired chronic urticaria-angioedema. Results were compared with the results of seven healthy control subjects. Moreover, data were compared with those of 13 subjects (10 males and 3 females, mean age: 24.7 years) suffering from allergic rhinitis. In acquired chronic urticaria-angioedema, serum tryptase levels (mean +/- S.D.: 9.6 +/- 4.3 microg/l) were significantly higher (P < 0.007) than those of the controls (mean +/- S.D.: 3.0 +/- 1.2 microg/l) and higher also than in allergic rhinitis (mean +/- S.D.: 6.1 +/- 2.4 microg/l, P < 0.03). The results underline the central role of mast cells in the inflammation of acquired chronic urticaria-angioedema.

Allergists and dermatologists have far more expertise in caring for patients with urticaria than other specialists

BACKGROUND

Urticaria is a common disease for which numerous treatments have been described, yet there is little information about what agents are commonly used to treat urticaria. There may be differences in the way in which urticaria is treated by different medical specialties.

OBJECTIVE

The purpose of this study was to characterize the visits and treatments of urticaria in office-based practices.

METHODS

National Ambulatory Medical Care Survey data from 1990 to 1997 were analyzed to determine patient populations, medications used, and physician specialties for visits of urticaria.

RESULTS

Women accounted for 69% of all patient visits, but an equal gender distribution was observed in patients 18 years of age and younger. There was a bimodal age distribution with peak visits in patients aged birth to 9 years and 30 to 40 years. H(1) antihistamines and systemic corticosteroids were used in 56% and 14% of visits, respectively. Other medications reported as useful in the treatment of urticaria were used in 12% of visits. Allergists and dermatologists had a mean of 47 and 37 visits per physician per year, respectively, compared with all other physicians who averaged fewer than 10 visits per physician per year. Allergists were the least likely to use a corticosteroid agent (6% of visits), whereas internists were the most likely (29% of visits). Dermatology and allergy recorded a relatively large percentage of visits for urticaria that were referred for their condition by other physicians (49% and 25% of visits, respectively).

CONCLUSION

We observed a bimodal utilization curve for age and urticaria not previously described. H(1) antihistamines remain the mainstay in treatment of urticaria, whereas the low use of systemic corticosteroids likely reflects physicians' understanding of their secondary function in the treatment of urticaria.

Urticarial vasculitis

Chronic or recurrent urticarial lesions are common in both primary care and referral medicine. Diagnosis and treatment are usually a challenge for both the patient and the medical practitioner. Most patients are eventually diagnosed with chronic idiopathic urticaria. IgG autoantibody to IgE receptor or IgE itself causes urticarial lesions in 30% of these patients. Only a minority (approximately 10%) of patients with chronic urticarial lesions have urticarial vasculitis. Although some cases are benign, urticarial vasculitis by itself can cause significant morbidity, and it is often a manifestation of a serious illness. Successful diagnosis and treatment of urticarial vasculitis requires careful assessment over time for underlying diseases like systemic lupus erythematosus, hypocomplementemic urticarial vasculitis syndrome, Sjögren's syndrome, and mixed cryoglobulinemia.

Idiopathic nonhistaminergic angioedema

PURPOSE

We sought to describe the characteristics of a group of patients with idiopathic nonhistaminergic angioedema and their response to prophylactic treatment with tranexamic acid.

METHODS

We identified 25 patients (15 men and 10 women; age at diagnosis 16 to 77 years) who had idiopathic nonurticarial angioedema that was not prevented by histamine-1 (H1) blockers. Known causes of angioedema were excluded by clinical history, physical examination, and diagnostic tests.

RESULTS

The median age at the onset of symptoms was 35 years (range 8 to 66). The frequency of attacks was > 12 per year for 16 patients, six to 11 per year for 6 patients, and one to five per year for 3 patients. All patients had cutaneous attacks, 13 (52%) reported swellings of the pharynx or larynx, and 5 (20%) had symptoms consistent with bowel angioedema. Because of the similarities between these patients and patients who are deficient in C1 inhibitor, the 15 patients with severe and frequent attacks were started on prophylactic treatment with the antifibrinolytic agent tranexamic acid, 1 g three times a day orally for 3 months, tapered according to its effectiveness. The symptoms of 11 patients decreased to less than one attack per year, and the remaining 4 patients had partial remissions (less than 4 attacks per year). Fourteen patients are still being treated with tranexamic acid.

CONCLUSION

Patients with idiopathic nonhistaminergic angioedema appear to have similar clinical features and response to treatment with tranexamic acid as those who are deficient in C1 inhibitor. This suggests that those two forms of angioedema might have, at least in part, a similar pathogenesis.

Participation of histamine H1 and H2 receptors in passive cutaneous anaphylaxis-induced scratching behavior in ICR mice

Scratching behavior associated with passive cutaneous anaphylaxis was examined and compared to that induced by compound 48/80 or histamine in ICR mice. Elicitation of passive cutaneous anaphylaxis, and intradermal injections of compound 48/80, histamine or serotonin induced both scratching behavior and vascular permeability increase in ICR mice. In mast cell-deficient WBB6F1-W/Wv mice, although histamine induced scratching behavior and vascular permeability increase, passive cutaneous anaphylaxis was not observed. Cetirizine and terfenadine significantly inhibited the scratching behavior and vascular permeability increase caused by passive cutaneous anaphylaxis, compound 48/80 and histamine. The histamine H1 receptor antagonists inhibited the vascular permeability increase almost completely, whereas they failed to abolish the scratching behavior. Famotidine and ranitidine significantly inhibited the scratching behavior caused by histamine. The histamine H2 receptor antagonists did not affect the vascular permeability increase caused by histamine. The combination of cetirizine and ranitidine abolished the histamine-induced scratching behavior. The combination, however, failed to potentiate the inhibition of passive cutaneous anaphylaxis-induced scratching behavior significantly. The results indicated that histamine induces scratching behavior in ICR mice through both histamine H1 and H2 receptors, and that histamine plays a major role in passive cutaneous anaphylaxis-induced scratching behavior. Histamine might also play an important role in compound 48/80-induced scratching behavior.