Mast cells are the key cells in chronic urticaria. Basophils are "bystanders."
Factors that contribute to the course and activity of chronic urticaria:
- coagulation cascade
- hormonal factors
- psychological status
Urticaria appearing on right arm. Image source: Wikipedia, public domain.
Second-generation antihistamines (at high doses) are the first-line treatment for chronic urticaria.
Update on chronic urticaria: focusing on mechanisms. Skin allergy. Mlynek, Agnieszka; Maurer, Marcus; Zalewska, Anna. Current Opinion in Allergy & Clinical Immunology. 8(5):433-437, October 2008.
Urticaria. Allergy Cases.