Pathergy
Pathergy is the hyperreactivity of the skin to any intracutaneous injection or needle stick (pathergy test).
It frequently occurs at the sites of blood draw. Originally described in 1935, this reaction is believed by some to be pathognomonic for Behcets disease.
The mechanism of pathergy in Behçet’s disease is unknown, but it is thought to be related to increased neutrophil chemotaxis.
The rate of a positive reaction varies in different populations, being more common in Japan and Turkey (50%–75%) and less common in England and the United States (10%–20%).
