In most cases of chronic urticaria, an underlying trigger is not found. Hodgkin's disease may be accompanied by urticaria. Cold urticaria with cryoglobulinemia is seen in multiple myeloma.

在大多数慢性荨麻疹患者，找不到触发原。伴有荨麻疹；冷球蛋白血症引起的荨麻疹见于多发性骨髓瘤。