Behçet’s disease

Question 1

Define Behcet’s disease.

Answer 1

Vasculitis that leads to mucocutaneous, ophthalmological, vascular, gastrointestinal, and CNS manifestations.

Question 2

How common is Behcet’s disease? Who is most affected?

Answer 2

Patients are most commonly from the Middle East, the Mediterranean region, and eastern Asia, with Japan and South Korea leading the list. 1 in 250 affected in Turkey.

More common in 20-30yrs

Males and females both affected but males get more severe symptoms + poor outcomes

Question 3

What is the aetiology of Behcet’s disease?

Answer 3

Unknown

Possible genetic predisposition

Unclear whether it is auto-immune or auto-inflammatory:

• Not typically associated with auto-antibodies or other AI conditions.
• Unlike auto-inflammatory conditions it abates with time and has a higher prevalence than most auto-inflammatory conditions.

Question 4

What is the pathophysiology of Behcet’s disease?

Answer 4

Unknown

Neutrophil hyperactivity - may be primary or secondary to cytokine directed activity. There may be different clusters of disease presentation each with their own pathogenesis.

Question 5

What are the signs and symptoms of Behcet’s disease?

Answer 5

Mouth and skin

• Apthous ulcers - painful, can last for 3 weeks
• Genital ulcers - not sexually transmitted
• Erythema nodosum - painful swellings on wlegs
• Acne-like spots on arms/legs

Eyes

• Uveitis - inflammation of middle layer of eye; anterior or posterior - eye pain, blurry vision, photophobia, photosensitivity.
• Can cause cataract(cloudy vision) or glaucoma (raised pressure)

Joints

• Knee/ankle pain, swelling, warmth
• Small joints can be affected
• Does not usually cause arthritis which damages joints

Vasculature

• Thrombophlebitis
• Aneurysms
• Stroke
• Headache, confusion
• Memory problems
• Dysphasias
• GI ulcers - cramping abdominal pain and diarrhoea; rarely PR bleeding

Question 6

How is Behcet’s disease diagnosed?

Answer 6

May be done by symptoms alone or tests to exclude other conditions which present similarly.

Pathergy test may be done.

Question 7

What investigations would you do for Behcet’s disease?

Answer 7

Pathergy testing - subcut skin prick using sterile needle –> papule/pustule formation within 48hrs.

Other:

• RF, ANA, ANCA - negative
• HLA-B51 - present ; more common in Behcet’s patients
• MRI angiography with contrast - indicated when large vessel phlebitis or CNS involvement is suspected; white matter changes in midbrain
• Colonoscopy/upper GI endoscopy - inflammation and aphthous-type ulcers, possibly vasculitis on biopsy
• CT angio chest/pulmonary angiography- may show pulmonary aneurysm, haemorrhage; indicated in haemoptysis