Behçet Syndrome and Crohn’s Disease: What Are the Differences?

Behçet syndrome (BS) is a variable vessel vasculitis that has pleiotropic manifestations. A 43-year-old male with a previous diagnosis of Crohn’s disease (CD) presented with deep venous thrombosis and bilateral superficial femoral artery aneurysms. A diagnosis of BS was made, and the patient was treated aggressively with immunosuppressive therapy and bilateral bypass surgery, attaining a favourable outcome. CD has many features that overlap with BS, and it may be challenging to distinguish between these two conditions, as our case illustrates. Nonetheless, the combination of venous thrombosis and arterial aneurysms should point the clinician towards a diagnosis of BS. LEARNING POINTS: Behçet syndrome is a variable vessel vasculitis of unknown aetiology that has pleiotropic manifestations. Crohn’s disease has many overlapping features with Behçet syndrome, namely gastrointestinal, cutaneous, articular, ocular and cardiac manifestations. The combination of venous thrombosis and arterial aneurysms should point the clinician towards a diagnosis of Behçet syndrome.