ABSTRACT

Chronic urticaria is defined by the presence of urticaria on most days of the week for longer than six weeks. Appereance of the lesions is not triggered by any reasons. Mast cell and basophil degranulation and releasing of histamine is the main cause of apperance of hives. In 1960, it was first hypothesised that chronic urticaria is an autoimmune condition. This hypothesis is supported by autoloug serum skin test positivity in some cases. It is not clear whether autoantibodies or serum or plasma factors triggered autoreactivity in cases with autolog serum skin test positivity. Compleman activity as also one of the key factors in basophil degranulation. Functional differences in basophils has also been shown by studies. Absence of characteristics of allergic late phase reaction in dermathopathologic specimen, suggests clues for better understanding the pathogenesis. In this review theories about pathogenesis of chronic urticaria will be discussed.