Chronic urticaria can be triggered by eradication of Helicobacter pylori.

Background: Participation of Helicobacter pylori (HP) in the pathogenesis of chronic spontaneous urticaria (CU) is subject to dispute, although its eradication proved to be effective for some patients.
Aims: To investigate the cases of CU following eradication of HP.
Methods: The cases of patients in whom CU was diagnosed following triple therapy for HP eradication were retrospectively reviewed. The identified patients underwent follow-up examination to exclude drug hypersensitivity and repeated autologous serum skin test (ASST) was done.
Results: From 831 patients with CU, 9 (1.08%) cases of CU related to triple therapy for HP eradication have been detected. In 8 (88.9%) patients CU was associated with positive ASST.
Conclusions: CU can be triggered by eradication of HP. The pathophysiological mechanisms of CU development following HP eradication are far from being clear, but it could be speculated that the systemic effects of HP eradication may involve some kind of immunomodulation, activating autoimmune mechanisms of CU.
(© 2012 Blackwell Publishing Ltd.)