Behçet's Disease and Tuberculosis: A Complex Relationship

Behçet's disease (BD) is a systemic vasculitis characterized by recurrent orogenital ulceration and several systemic manifestations (such as gastrointestinal involvement, vascular disease or arthritis). The pathogenesis is still unknown but the trigger role of certain pathogens such as Mycobacterium tuberculosis is well documented. Furthermore, patients with BD are more susceptible to tuberculosis due to immunity defects. Here, we describe the case of a 70-year-old woman with a history of recurrent oral aphthae and inflammatory arthritis presenting with extensive thrombosis of left upper limb major veins, a positive HLA B51 genotype and colon ulceration; hence, BD diagnosis was made after excluding other causes. Simultaneously, the patient had cutaneous abscesses not associated with immunosuppressive therapy with continuous development, and after recurrent negative tuberculosis work-up, M. tuberculosis was isolated in an abscess culture.

Patients with Behçet's disease (BD), in the absence of anti-TNF-alpha therapy, have increased susceptibility to tuberculosis due to a defect in cell-mediated immunity.It is very important to distinguish between BD and pseudo-Behçet's at the onset of tuberculosis, since Behçet-like manifestations achieve complete remission with anti-bacillar therapy.Cutaneous tuberculosis is a rare condition, with a wide clinical spectrum; hence, high clinical suspicion, and sometimes, multiple bacteriological examinations, are required in order to diagnose.