Urticaria/arthritis syndrome: report of four B51 positive patients.

The development of articular manifestations in the course of chronic urticaria or in urticarial vasculitis has been widely reported. It is not completely clear, however, whether common pathogenetic mechanisms are involved in all patients with these clinical features. Four consecutive patients with simultaneous urticarial and articular manifestations, but without any evidence of an immune complex mediated disease, are described. The HLA-B51 antigen was positive in all these patients, suggesting that a common genetic background may be present in some cases of urticaria with articular complaints.