Bechet's disease (Bechet Syndrome)

Was first described by Turkish dermatologist Hulusi Bechet as a triad of symptoms, consisting of recurring oral ulcers, recurring genital ulcers and eye involvement.

Etiology

• Abnormal immune response in a genetically susceptible host, characterised by systemic perivascularitis and hyperactivity of neutrophils with enhanced chemotaxis and elevated proinflammatory cytokines (IL-8, IL-17, and TNF-A).
• Most frequently linked with HLA-B51 genotype (60% of patients).
• Environmental factors : Organophosphates, Organochlorides, Heavy metal intoxication, and allergens.
• Oral microbiota : Streptococcus sanguis and Streptococcus oralis.

Clinical Findings

• Characterised by exacerbations and remissions, with duration of attacks ranging between few days to few weeks.

• Oral mucosa is the most common site, followed by the genital area.

• Oral manifestations :

  • Recurring oral ulcers (90% of patients) : usually the first to appear, and similar clinically and histologically to Reccurent Aphthous Stomatitis.

• Genital lesions :

  • Males : Ulcers of the scrotum and penis.
  • Females : Ulcers of the labia.

• Ocular lesions :

  • Photophobia and irritation.
  • Conjunctivitis, Uveitis, Retinal vasculitis.
  • Hypopyon.
  • Vascular occlusion.
  • Optic atrophy.

• Skin lesions (50% of patients) :

  • Papulopustular lesions (acneiform) or pseudofolliculitis.
  • Erythema nodosum.
  • Superficial thrombophlebitis.
  • Cutaneous ulcers and nodules.
  • Cellulitis type lesions.

• Complications :

  • Blindness.
  • Thrombosis and embolism.
  • Rupture of large-vessel aneurysms.
  • Arthritis (40% of cases).
  • CNS Involvement - Brainstem syndrome, involvement of cranial nerves, or nerve degeneration resembling multiple sclerosis.
  • Thrombophlebitis.
  • Intestinal ulceration.
  • Renal, Cardiac and Pulmonary involvement.

International Criteria for Bechet's Disease 2010

• A score of 4 or more points predicts Bechet's disease with 95% certainity, 98% if the pathergy test is performed.
• Oral Aphthous Stomatitis (3 or more attacks in one year) : 2 points.
• Genital Ulceration (Recurrent ulcers or scarring) : 2 points.
• Ocular Lesions (Uveitis or retinal vasculitis) : 2 points.
• Skin Lesions (Follicular pustular rash or erythema nodosum) : 1 point.
• CNS involvement (Any involvement) : 1 point.
• Vascular Manifestations (Superficial phlebitis, deep vein thrombosis, large vein thrombosis, arterial thrombosis, and aneurysm) : 1 point.
• Positive Pathergy Test (optional) : 1 point.

Laboratory Findings

• Hypergammaglobulinemia.
• Leukocytosis with eosinophilia.
• Elevated ESR, C-reactive protein and C3, C4 complements, during the active phases of disease.
• Platelet rosette formation around neutrophils, seen in acute phases (disappear after recovery).

Management

• Depends on the severity and sites of involvement.
• Requires multidisciplinary approach, with the goal to prevent irreversible organ damage.
• Cyclosporine and Tacrolimus are the main treatments, with steroids for acute exacerbations.
• Thalidomide and topical tacrolimus are most effective for oral ulcers.
• Systemic therapy with colchicine, pentoxifylline, and dapsone is often useful when mucocutaneous lesions are frequent or severe.
• In refractory cases, thalidomide, azathioprine, or biological agents such as TNF-A antagonists (Infliximab, Etanercept) and interferon-alpha, may be necessary.

Points to Note

• Hypopyon is a visible layer of pus (exudate rich in white blood cells) seen in the anterior chamber of eye (found in 12% of cases).
• Blindness is a possible complication of Bechet's disease and hence, periodic evaluation by an ophthalmologist is necessary.
• Pathergy test (Neutrophilic vascular reaction of leukocytoclastic vasculitis) : The doctor inserts a 20-gauge or smaller needle obliquely into the skin under sterile conditions and checks for 24-48 hours, how the immune system reacts to a minor injury.

References

1. Burket's Oral Medicine, 13th Edition, Michael Glick, Martin S. Greenberg, ,Peter B. Lockhart, Stephen J. Challacombe, Wiley Blackwell.

2. Shafer, Hine, Levy Shafer's Textbook of Oral Pathology (7th Edition), Editors - R Rajendran, B Sivapathasundharam, Elsevier.

3. Cawson's Essentials of Oral Pathology and Oral Medicine, 9th Edition, EW Odell, Elsevier.

4. Contemporary Oral Medicine, A Comprehensive Approach to Clinical Practice, Camile S Farah, Ramesh Balasubramaniam, Michael J Mccullough, Springer.

5. Anil Govindrao Ghom, Savita Anil Ghom (Lodam) - Textbook of Oral Medicine - Jaypee Brothers Medical Publishers (P) Ltd (2014).

6. The image used is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license.

   • Description : Bechets disease Oral Ulcer in patient with the disease.
   • Source : http://dermatology.cdlib.org/1611/articles/18_2009-10-20/2.jpg.
   • Author : Ahmet Altiner MD, Rajni Mandal MD.

*This article is an excerpt from the above mentioned books and Medical Sutras does not make any ownership or affiliation claims.