KYNA/QA↓; TRP↓  CRP was positively correlated with QA while negatively with KYNA/3-HK and KYNA/QA.  KYNA/3-HK was positively associated with hippocampal volume and KYN/3-HK was significantly associated with total amygdalar volume in the BD group. Here, CRP is linked to Behcet disease.