The spectrum of chronic urticaria

Abstract

Chronic urticaria is a common heterogeneous condition that can be quite debilitating. There are a number of potential causes of urticaria, and the severity and clinical pattern can vary considerably from patient to patient. Eighty to 90% of patients with chronic urticaria have no specific external cause for their disease, which is therefore labeled "chronic idiopathic urticaria." We now know, however, that up to 30-50% of idiopathic cases may be autoimmune or related to mast cell and basophil abnormalities. There is evidence of an autoantibody to the high-affinity receptor for IgE (FcepsilonRI), specifically binding to the alpha-chain (FcepsilonRIalpha), which may be pathogenic. At this point in time, the gold standard for detecting clinically relevant autoantibodies to FcepislonRI is the functional in-vitro donor basophil histamine release assay. The exact prevalence and role of these autoantibodies is still under investigation. Histamine antagonists are the mainstays of therapy. For patients whose symptoms are not controlled by antihistamines alone, there are a number of adjunct therapy options, but there is still a need to develop better agents for this disease.

The link between chronic spontaneous urticaria and metabolic syndrome

“…The autologous serum skin test (ASST) is a simple screening tool able to detect autoreactivity related to the presence of circulating histamine-releasing factors of any type, and not only of functional autoantibodies (1). Current evidence supports the possible contribution of other pathomechanisms, including the dysregulation of intracellular signalling pathways in basophils and mast cells, an abnormal innate immunity response, and the simultaneous activation of inflammatory response and coagulation system (2)(3)(4). With regard to the last aspect in more detail, significantly increased circulating levels of inflammatory markers [such as C-reactive protein (CRP) and interleukin (IL)-6], fibrin degradation products and D-dimer have been associated with the active phase of CSU, in correlation with disease severity (5).…”

“…Various aetiological factors and mechanisms have been implicated in the development of CSU, but a specific cause is unidentifiable in most cases. Disease pathogenesis remains incompletely understood, although an autoimmune basis is increasingly being recognized based on the presence of functional histamine-releasing autoantibodies in a subset of patients (2,3). The autologous serum skin test (ASST) is a simple screening tool able to detect autoreactivity related to the presence of circulating histamine-releasing factors of any type, and not only of functional autoantibodies (1).…”

Positivity of autologous serum skin test in patients with alopecia areata and vitiligo and in healthy individuals

“…Ancak hastaların %80-90'ında hiçbir etiyolojik neden saptanamaz. Etiyolojik neden saptanamayan bu grup KİÜ olarak sınıflandırılır 1 . Yapılan çalışmalarda KİÜ grubundaki hastaların ~%40-50'sinde histamin salınımına yol açan otoantikorlar olduğu gösterilmiştir.…”

“…Yapılan çalışmalarda KİÜ grubundaki hastaların ~%40-50'sinde histamin salınımına yol açan otoantikorlar olduğu gösterilmiştir. Böylece eskiden kronik idyopatik ürtiker olarak bilinen bu hasta grubu günümüzde KİÜ ve KOÜ olarak iki alt grupta incelenmeye başlanmıştır [1][2][3][4] . Güven ve ark.…”

“…Kronik idiyopatik ürtikerli (KİÜ) hastaların bir grubunda sirkülasyonda dermal mast hücreleri ve bazofiller üzerindeki yüksek afiniteli IgE reseptör FcεRIα'ya (%35-40) karşı, daha az sıklıkla da IgE'nin kendisine (%5-10) karşı histamin salgılatan IgG otoantikorları tespit edilmiş ve bu gruba kronik otoimmün ürtiker (KOÜ) adı verilmiştir [1][2][3][4][5][6][7][8] . Otolog serum deri testi (OSDT), KOÜ tanısında kullanılan in vitro bazofil histamin salınım aktivitesini en iyi gösteren in vivo test yöntemi olup yapılması kolay ve ucuz bir testtir 9 .…”