Behçet's Disease (BD) is a systemic disorder with an unknown etiopathogenesis. The need for clinical criteria in the establishment of diagnosis is of great importance. We present the case of a 27-year-old man with BD, who had a surgical operation during the active period of his disease and experienced subsequent complications. Cutaneous hyper-reactivity response to minor cutaneous trauma--the pathergy phenomenon--is found in most patients with BD. Theoretically, major traumas may lead to major reactions in the skin or any of the organs. In practice, we observed that while there was a severe inflammatory reaction--histopathologically a superficial perivascular dermatitis--which developed at the incision site, the systemic symptoms of the disease increased in spite of intensive treatment of the condition.