Inflammatory Bowel Disease (IBD): This includes conditions like Crohn's disease and ulcerative colitis, which can present with similar gastrointestinal and systemic symptoms as Behcet's disease, such as oral ulcers, genital ulcers, and ocular inflammation.

Reactive Arthritis: Previously known as Reiter's syndrome, this form of arthritis occurs as a reaction to an infection elsewhere in the body, often presenting with symptoms like conjunctivitis, urethritis, and arthritis, which can mimic some of the manifestations of Behcet's disease.
Systemic Lupus Erythematosus (SLE): An autoimmune disease that can affect various parts of the body, including the skin, joints, kidneys, brain, and other organs, with symptoms overlapping with Behcet's, such as oral ulcers and arthritis.
Sjögren's Syndrome: An autoimmune disorder characterized by its effects on exocrine glands, particularly the salivary and lacrimal glands, leading to dry mouth and dry eyes, which can be confused with the ocular and mucocutaneous manifestations of Behcet's.

Giant Cell Arteritis: A condition where the arteries, particularly those in the head, become inflamed, which can lead to blindness if not promptly treated. While less common in the differential for Behcet's, the potential for severe complications makes it crucial not to miss.
Wegener's Granulomatosis (Granulomatosis with Polyangiitis): A rare autoimmune disorder that causes blood vessel inflammation, which can affect various organs, including the lungs, kidneys, and sinuses. Its potential for severe organ damage necessitates consideration in the differential diagnosis.

Relapsing Polychondritis: A rare autoimmune disorder characterized by recurring episodes of cartilage inflammation, which can affect the ears, nose, trachea, and joints. While rare, its potential to cause significant morbidity, especially through airway involvement, warrants consideration.
M MAGIC Syndrome: A rare condition that overlaps with Behcet's disease, characterized by the presence of mouth and genital ulcers along with inflammation of the eyes (uveitis), and it stands for " Mouth And Genital ulcers with Inflamed Cartilage". It's a rare but important differential due to its overlapping symptoms with Behcet's.