Hives and expectation

Townsend Letter for Doctors and Patients, May, 2006 by Robert A. Anderson

In this case report, a subject known to be prone to the development of hives was tested by striking the forearm with a small paddle, leading to the immediate development of a reactive hyperemia and development of an urticarial (hive-like) reaction in the area of skin touched by the paddle. Some days later, when the reaction had completely dissipated, the patient was again tested by being told that the paddle-blow experiment was to be repeated. On this second occasion, however, a sham blow was delivered to the arm by stopping the paddle about one-quarter inch from the skin. This resulted in the exact same reactive hyperemia and hive formation developing in the projected footprint of the blow, despite the fact that the skin had not actually been struck.

Graham DT. The pathogenesis of hives: experimental study of life situations, emotions and cutaneous vascular reactions. Proc Ass Res Nerv Ment Dis. 1950; 29:987-89.

COMMENT: Hives are often not well understood, but are most often assumed to be of allergenic origin. This case was probably dealing with an extreme variation of the urticarial process called dermographism, in which even light pressure on the skin results in prompt development of hives. The obvious point of publishing this case history is to widen the thinking about the chain of events that leads to reaction in a target organ with apparently more than just the participation of the immune system. The belief system here is clearly implicated. The sham blow is in effect a placebo, because the patient anticipates or expects the blow to be real and imagines the result, which does indeed occur. To what extent are our allergic reactions limited to the immune system, and how are the mental and emotional systems integrated into this response? For someone whose bronchospasm has been triggered by exposure to a given inhalant, how much of his/her next episode on exposure is "real," and how much might be "imagined." We need to think more broadly, outside the proverbial box.