Behçet's disease.
Behçet's disease is a variable vasculitis that can affect almost any organ. The classic features are recurrent oral ulcers, genital ulcers, and uveitis — but the disease can involve skin, joints, GI tract, central nervous system, and blood vessels of any size. It is most common along the historical Silk Road (Mediterranean to East Asia) and is strongly associated with HLA-B51. Treatment depends on severity: colchicine, apremilast, azathioprine, anti-TNF biologics, and IL-1 blockers all have roles. Posterior uveitis is sight-threatening and requires urgent treatment.
The mechanism, the disease that crosses every boundary.
Behçet's is one of the most variable diseases in rheumatology — small-vessel, medium-vessel, and large-vessel involvement can all occur. Four mechanisms drive what patients experience:
Variable vasculitis
Behçet's can affect blood vessels of any size — venous, arterial, capillary. This explains the diversity of manifestations and complications (DVT, pulmonary artery aneurysms, cerebral venous thrombosis, intestinal vasculitis).
HLA-B51 association
HLA-B51 is the strongest genetic association in Behçet's, found in 50–70% of patients in high-prevalence regions. It doesn't cause the disease but identifies susceptibility.
IL-1, IL-6, TNF, IL-17 involvement
Multiple inflammatory cytokines are elevated. This is why several treatment options work (anti-TNF for severe disease, IL-1 inhibitors for resistant cases, IL-17 blockers being studied).
Pathergy
An exaggerated skin reaction to minor trauma (pathergy phenomenon) is characteristic, especially in patients from high-prevalence regions. The pathergy test is part of diagnosis in classical disease.
The 4-step plan, applied to Behçet's.
Get the right diagnosis
ISBD (International Study Group for Behçet's Disease) criteria. Clinical pattern is central — recurrent oral ulcers (3 or more per year) plus two of: genital ulcers, eye involvement, skin lesions, or positive pathergy. HLA-B51 supports the diagnosis. Ophthalmology evaluation at diagnosis for any visual symptom.
Learn more about labs →Clean up your food
Mediterranean pattern. Some patients identify food triggers for oral ulcers (acidic foods, nuts, citrus). Adequate hydration and oral hygiene support ulcer healing.
Behçet's & diet →Detox your daily life
Stress is a well-recognized flare trigger in Behçet's. Sleep, stress regulation, and minimizing minor trauma to skin (pathergy) all matter.
Behçet's & environment →Build a stronger body
Gentle exercise when stable. Avoid contact sports during active disease (pathergy). Pulmonary considerations if vascular involvement (Hughes-Stovin syndrome).
Behçet's & exercise →
Go deeper.
Common misconceptions.
"It's just mouth sores."
Oral ulcers are the entry point of Behçet's, but the disease is multi-system. Eye involvement is sight-threatening. Vascular involvement (DVT, pulmonary aneurysm) is life-threatening. CNS involvement is disabling. Treating it as 'just mouth sores' misses the systemic risk.
"Behçet's only occurs in certain ethnicities."
Behçet's is most common along the Silk Road geographic distribution (Mediterranean, Middle East, East Asia) — but it occurs worldwide. Patients of any background can develop it. Geographic stereotyping causes diagnostic delays in patients from non-classical populations.
"There's no good treatment."
Treatment has improved dramatically. Colchicine controls mucocutaneous disease. Apremilast is FDA-approved for oral ulcers. Anti-TNF agents (infliximab, adalimumab) are highly effective for severe eye, vascular, and CNS disease. IL-1 inhibitors work in colchicine-refractory cases. The era of 'just live with it' is over.
When to see a rheumatologist.
See a rheumatologist if you have:
- Recurrent oral ulcers (3 or more episodes per year)
- Genital ulcers (current or scarring from past episodes)
- Eye inflammation (uveitis, retinal vasculitis)
- Characteristic skin lesions (erythema nodosum, papulopustular)
- Pathergy phenomenon (exaggerated skin reaction to minor trauma)
- Unexplained venous or arterial thrombosis at a young age
- Neurological symptoms plus oral ulcers
The ISG criteria require recurrent oral ulcers (3 or more per year) plus two additional features. Behçet's can mimic other conditions — early referral to rheumatology and ophthalmology matters.
- International Study Group for Behçet's Disease. Criteria for diagnosis of Behçet's disease. Lancet, 1990. PubMed 1970409
- Hatemi G, et al. 2018 update of the EULAR recommendations for the management of Behçet's syndrome. Ann Rheum Dis, 2018. PubMed 29625968
- Hatemi G, et al. Apremilast for oral ulcers of Behçet's syndrome (RELIEF). N Engl J Med, 2019. PubMed 31532960
- Yazici Y, Yurdakul S, Yazici H. Behçet's syndrome. Curr Rheumatol Rep.