Delayed pressure urticaria: treatment with dapsone

Potential Therapeutic Approaches for Chronic Urticaria: Beyond H1-Antihistamines and Biologics

Chronic urticaria is a disease that can significantly impact a patient's quality of life and ability to function. There are effective treatment options, such as nonsedating antihistamines or biologics, but some patients do not respond to these therapies, or the therapies are not available or affordable to all patients. This review aims to summarize potential treatment strategies for patients (1) who do not respond to antihistamines and (2) cannot readily access or do not respond to biologics. The review emphasizes the importance of sound clinical practice, including correct diagnosis of chronic urticaria phenotypes, treatment of associated comorbidities, and consideration of add-on pharmacological and nonpharmacological approaches. Although some treatments may lack high-quality evidence, they may still be justifiable in certain cases, provided that there is shared decision-making, regular reassessment, and early recognition of adverse events.

Delayed Pressure Urticaria: A Systematic Review of Treatment Options

BACKGROUND

Delayed pressure urticaria (DPU) is characterized by recurrent erythematous and often painful swelling after the skin is exposed to sustained pressure. Treatment is challenging. Antihistamines, the first-line and only approved treatment, are often not effective.

OBJECTIVE

To systematically review the treatment options for DPU.

METHOD

A literature search of electronic databases for all relevant articles published till April 29, 2019, was conducted using the search terms "delayed pressure urticaria" and "pressure urticaria." This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses recommendations.

RESULTS

Twenty-one studies (8 randomized controlled trials [RCTs], 10 retrospective cohort studies, and 3 open-label prospective studies) were included. Second-generation H₁ antihistamines (sgAHs) were effective in 3 RCTs. The combination of an sgAH and montelukast (2 RCTs) or an sgAH and theophylline (1 non-RCT) was more effective than the sgAH alone. The disease improved with omalizumab (4 non-RCTs), sulphones (3 non-RCTs), oral prednisolone (1 RCT and 2 non-RCTs), intravenous immunoglobulin (1 non-RCT), and gluten-free diet (1 non-RCT). There are no studies on updosing of antihistamines over standard dosage in DPU.

CONCLUSIONS

Overall, the quality of studies on DPU is low. Because of the lack of other evidence, antihistamines remain the first-line therapy. Updosing of sgAHs could be considered in patients with uncontrolled symptoms on the basis of the extrapolation of evidence from chronic spontaneous urticaria, even though there is no evidence of its efficacy over standard dosage. Addition of montelukast may be considered. Omalizumab or sulphones may be used in treatment-resistant patients. High-quality DPU studies should be conducted.

Dapsone in dermatology and beyond

Dapsone (4,4′-diaminodiphenylsulfone) is an aniline derivative belonging to the group of synthetic sulfones. In 1937 against the background of sulfonamide era the microbial activity of dapsone has been discovered. Shortly thereafter, the use of dapsone to treat non-pathogen-caused diseases revealed alternate antiinflammatory mechanisms that initially were elucidated by inflammatory animal models. Thus, dapsone clearly has dual functions of both: antimicrobial/antiprotozoal effects and anti-inflammatory features similarly to non-steroidal anti-inflammatory drugs. The latter capabilities primarily were used in treating chronic inflammatory disorders. Dapsone has been investigated predominantly by in vitro methods aiming to get more insights into the effect of dapsone to inflammatory effector cells, cytokines, and/or mediators, such as cellular toxic oxygen metabolism, myoloperoxidase-/halogenid system, adhesion molecules, chemotaxis, membrane-associated phospholipids, prostaglandins, leukotrienes, interleukin-8, tumor necrosis factor α, lymphocyte functions, and tumor growth. Moreover, attention has been paid to mechanisms by which dapsone mediates effects in more complex settings like impact of lifespan, stroke, glioblastoma, or as anticonvulsive agent. Additionally, there are some dermatological investigations in human being using dapsone and its metabolites (e.g., leukotriene B₄-induced chemotaxis, ultraviolet-induced erythema). It could be established that dapsone metabolites by their own have anti-inflammatory properties. Pharmacology and mechanisms of action are determining factors for clinical use of dapsone chiefly in neutrophilic and/or eosinophilic dermatoses and in chronic disorders outside the field of dermatology. The steroid-sparing effect of dapsone is useful for numerous clinical entities. Future avenues of investigations will provide more information on this fascinating and essential agent.

The Management and Treatment of Chronic Urticaria

Chronic urticaria (CU) is a challenging and frequently encountered diagnosis characterized by the presence of evanescent wheals that persist for greater than 6 weeks. It is estimated that 15% to 25% of the US population are affected at some time in their lives with urticaria and that 33% of all urticaria cases are considered to be chronic. Although acute urticaria is generally benign and self-limiting, serious medical illness may occur with CU. The incidence of CU is estimated to be as high as 5% in the general population and greater than 10% when surveying allergy and dermatology patients. CU is an episodic, pruritic disorder in which 45% to 90% of patients will not have an identifiable cause and occurs 4 times more often in females than males. The average disease duration of CU is between 2 and 5 years, and its typical onset is in the third to fourth decade of life. CU is thought to have the most impact on quality of life than any other allergic disease. This article will provide a clinical update and review on the management and treatment of CU.

Dapsona como alternativa no tratamento de urticária crônica não responsiva a anti-histamínicos

FUNDAMENTOS: A urticária crônica é dermatose que interfere negativamente na qualidade de vida de seus portadores. O tratamento clássico com anti-histamínicos muitas vezes é ineficaz. OBJETIVO: Avaliar a eficácia e a segurança do uso da dapsona no tratamento da urticária crônica não responsiva a anti-histamínicos. METÓDOS: Realizou-se estudo retrospectivo mediante a revisão de prontuários de pacientes atendidos em ambulatório especializado em urticária entre novembro de 1996 e março de 2007. RESULTADOS: Foram avaliados 20 pacientes com urticária crônica de difícil controle, que receberam tratamento com dapsona na dose de 100mg/dia. Associados à dapsona, foram mantidos anti-histamínicos em altas doses, que, isoladamente, não controlavam os sintomas. Quatorze pacientes (70%) responderam com melhora do quadro, observada tanto na diminuição ou desaparecimento das lesões quanto na redução do prurido; três (15%) não obtiveram nenhum sucesso com a medicação; e três (15%) tiveram o tratamento suspenso em decorrência de efeitos colaterais. CONCLUSÃO: Neste estudo, conclui-se que a dapsona é opção segura e eficaz para pacientes com urticária crônica grave não responsiva a anti-histamínicos.

Therapeutic alternatives for chronic urticaria: an evidence-based review, part 1

OBJECTIVE

To evaluate the use of alternative therapies for chronic urticaria refractory to first-line treatments in an evidence-based manner.

DATA SOURCES

MEDLINE searches were performed cross-referencing urticaria with the names of multiple therapies. Articles were then reviewed for additional citations. Articles published after 1950 were considered.

STUDY SELECTION

All articles, including case reports, were reviewed for soundness and relevance.

RESULTS

Experience has been reported for a wide variety of alternative therapies in the treatment of chronic idiopathic and physical urticarias. Evidence for most agents is limited to anecdotal reports. The second-line therapies reviewed are also categorized based on criteria of safety, efficacy, convenience, and cost, in relation to the first-line antihistamines.

CONCLUSIONS

Alternative agents should be considered in patients with chronic urticaria who are both severely affected and unresponsive to antihistamines. Although monitoring for toxicity is important in management with many alternative agents, safety is favorable compared with corticosteroids.

Chronic Urticaria

Chronic urticaria is a common condition that can be very disabling when severe. A cause for chronic idiopathic urticaria (CIU) is only infrequently identified. Potential causes include reactions to food and drugs, infections (rarely) and, apart from an increased incidence of thyroid disease, uncomplicated urticaria is not usually associated with underlying systemic disease or malignancy. About one-third of patients with CIU have circulating functional autoantibodies against the high affinity IgE receptor or against IgE, although it is not known why such antibodies are produced, or how the presence of such antibodies alters the course of the disease or response to treatment. There are only a few publications relating to childhood urticaria, but it is probably similar to the adult form, except that adult urticaria is more common. The diagnosis is based on patient history and it is vital to spend time documenting this in detail. Extensive laboratory tests are not required in the vast majority of patients. Chronic urticaria resolves spontaneously in 30-55% of patients within 5 years, but it can persist for many years. Treatment is aimed firstly at avoiding underlying causative or exacerbating factors. Histamine H1 receptor antagonists remain the mainstay of oral treatment for all forms of urticaria. The newer low-sedating antihistamines desloratadine, fexofenadine, levocetirizine and mizolastine should be tried first. Sedating antihistamines have more adverse effects but are useful if symptoms are causing sleep disturbance. Low-dose dopexin is effective and especially suitable for patients with associated depression. There is controversy as to whether the addition of an histamine H2 receptor antagonist or a leukotriene antagonist is helpful. For CIU, second-line agents include ciclosporin (cyclosporine) [which is effective in approximately 75% of patients], short courses of oral corticosteroids, intravenous immunoglobulins and plasmapheresis, although the last two were found to be beneficial in small trials only. Treatments for CIU with only limited or anecdotal supportive evidence include sulphasalazine, methotrexate, stanazol, rofecoxib and cyclophosphamide. The efficacy of photo(chemo)therapy is controversial. Physical urticarias may respond to H1 receptor antagonists, although in delayed pressure urticaria, and cold, solar and aquagenic urticaria, the response may be disappointing. Second-line agents for physical urticarias vary depending on the urticaria and most have limited supportive evidence. The potential for spontaneous resolution, the variation in the disease activity and the unpredictable nature of the disease makes the efficacy of treatments difficult to assess.

Alternative treatments for severely affected patients with urticaria

A none sedating antihistamine is the treatment of choice for most patients with urticaria. There are, however, several occasions where alternative treatments are appropriate. In this paper these alternative treatments of various types of urticaria are discussed. The treatment of anaphylactic shock where urticaria often is the first sign is also discussed. In all types of urticaria it is important to work with the patient and try to eradicate the cause or inhibit the mediators giving the clinical signs.

Dermatologic therapy: 1992

This article reviews therapeutic studies reported in the English-language literature during 1992. Readers should review the original article in full before attempting any experimental or controversial therapy.