TY - JOUR T1 - Pathergy test JF - Practical Neurology JO - Pract Neurol SP - 301 LP - 302 DO - 10.1136/practneurol-2011-000072 VL - 11 IS - 5 AU - Mark R Baker AU - Emma V Smith AU - Osheik A Seidi Y1 - 2011/10/01 UR - http://pn.bmj.com/content/11/5/301.abstract N2 - A positive pathergy test is one of the four minor diagnostic criteria for Behçet's disease. However, there is no consensus as to the optimal method of testing pathergy in clinical practice. Here we describe an approach to performing the pathergy test based on the best available evidence and also explain how to interpret the result. Finally, we discuss briefly in which patients a neurologist might consider pathergy testing. Pathergy is a non-specific hypersensitivity reaction to skin trauma that can occur in patients with Behçet's disease. The histology of pathergy is characterised by variable epidermal thickening, epidermal cell vacuolisation, subcorneal pustule formation, upregulation of cell adhesion molecules (including intercellular adhesion molecule 1, endoglin, E-selectin and P-selectin1) and mixed perivascular inflammatory cell infiltrates (neutrophils, CD4 positive T cells and macrophages), which appear at 4 h, are densest at 24 h and begin to diminish after 48 h.1 2 The skin pathergy test is one of the minor diagnostic criteria for Behçet's disease … ER -