Chronic urticaria associated with chronic myelomonocytic leukemia.

Although chronic urticaria is usually idiopathic, in rare cases it may be a sign of underlying malignancy. We describe the first case of chronic urticaria associated with chronic myelomonocytic leukemia. The urticarial lesions healed successfully with etoposide, an antineoplastic agent. This case demonstrates that cases of chronic urticaria should not to be labeled as idiopathic until diligent evaluation has failed to reveal a cause.