S100B and Behcet disease: A total of 25 patients progressed to BD (14 within the first 72 hours). There was a difference in the levels of S100b collected from the jugular vein and the peripheral vein, with higher levels in the jugular vein. The transcranial gradient (the difference between the levels of S100b from the jugular vein and the peripheral vein) was significantly greater upon admission to the ICU in patients who progressed to BD.