Behçet's disease and genes within the major histocompatibility complex region

Successful mesenchymal stem cell treatment of leg ulcers complicated by Behcet disease: A case report and literature review

RATIONALE

Behçet disease (BD) is a recurrent vasculitis characterized by oral and genital mucous membrane ulcers, uveitis, and skin lesions but only rarely leg ulcers. To our knowledge, no efficacious therapy has been described for BD patients with complicating, destructive leg ulcers.

PATIENT CONCERNS

Here, We report the case of a 55-year-old woman with generalized erythema nodosum-like, papulopustular lesions, recurrent oral and genital ulcers accompanied with recurrent leg ulcers and trouble walking.

DIAGNOSES

Based upon the patient's clinical feature and positive pathergy test , BD was confirmed.

INTERVENTIONS

Conventional immunosuppressive therapy and anti-tumor necrosis factor inhibitors, adalimumab and etanercept, had no demonstrable clinical effect. Mesenchymal stem cell (MSC) injection combined with low-dose prednisone and thalidomide, however, completely ameliorated the ulcers on one leg, significantly improved ulcers on the other leg, and returned normal function to both legs.

OUTCOMES

The ulcerative lesions remained in remission, and the affected leg functioned normally after 34 months' follow-up.

LESSONS

Our experience suggests that MSC infusion might be a potentially successful therapy for intractable drug-resistant BD patients with concomitant leg ulcer.

Inflammation-related cytokine gene polymorphisms in Behçet's disease

Behçet's disease (BD) is a complex, multisystemic inflammatory disorder of unclear etiology. Single nucleotide polymorphisms in tumor necrosis factor (TNF) and interleukin (IL)-10 genes have been implicated in susceptibility to BD with inconsistent results in several ethnic populations. The aim of this case-control study was to evaluate the association of TNF-α (-308G/A), TNF-β (+252A/G), and IL-10 (-1082G/A, -819C/T, and -592 C/A) polymorphisms with susceptibility of BD in Saudi patients. Molecular genotyping of TNF-α, TNF-β, and IL-10 gene polymorphisms was performed to analyze the alleles and genotypes distribution in 272 Saudi subjects, including BD patients (61) and healthy controls (211). The frequencies of allele A and genotype GA of TNF-α (-308G/A) were significantly higher, whereas those of allele G and genotypes GG were significantly lower in BD patients than controls, indicating that A allele and GA genotype are susceptible, while G allele and GG genotype may be refractory to BD. The distribution of frequencies of alleles and genotype of TNF-β (+252A/G) promoter polymorphism was not significantly different between BD patients and healthy controls. Genotypes 1082GG, -819TT, and 592AA of IL-10 polymorphisms are significantly associated with susceptibility risk of BD, while genotypes 1082AA, 1082GA, 819CC, 819CT, 592CC, and 592CA are resistant to BD. This study indicates that TNF-α (-308G/A) and IL-10 (-1082G/A, -819C/T, and -592C/A) polymorphisms are associated with risk of BD susceptibility in Saudi patients. However, larger scale studies in Saudi population as well as in other ethnicities are needed to confirm this association.

The great masquerader: Behcet's disease

This report describes the case of a 44-year-old Caucasian woman of Northern European descent with a medical history of pyoderma gangrenosum, chronic abdominal pain and erythema nodosum which required intermittent use of high-dose steroids that failed to improve her symptoms. The patient was initially diagnosed with Crohn's disease and most recently with sclerosing mesenteritis. She presented to the hospital with worsening abdominal pain. She was found to have recurrent painful aphthous oral, genital and perianal ulcers and a clinical diagnosis of Behçet's disease was made. Her hospitalisation was complicated by haemoptysis, and bronchoscopy revealed alveolar haemorrhage. Treatment was initiated with three days of pulse intravenous solumedrol 1 g/day and cyclophosphamide at 700 mg/m(2). The case had a favourable outcome despite the initial diagnostic challenges. This report emphasises that systemic diseases, including Behçet's disease, can have variable presentations and can be frequently misdiagnosed.

Behçet's syndrome pathophysiology and potential therapeutic targets

Behçet syndrome is a systemic inflammatory disorder characterized by multiorgan involvement such as oral and genital ulcers, uveitis, skin lesions as well as by less frequent, but often more severe, central nervous system and vascular manifestations. The pathogenetic mechanisms are still incompletely known; however the interaction between a specific genetic background and environmental or infectious factors certainly contributes to the immune dysregulation that characterizes this disease. The discovery of new immunological pathways in Behçet syndrome pathogenesis may help us to set up new treatments. In this review, we will focus our attention on the possible mechanisms underlying Behçet syndrome pathogenesis and their potential role as novel therapeutic targets.

[Update: Behçet's disease]

Behçet's disease (BD) is now mentioned in the latest Chapel Hill nomenclature of vasculitides and is classified under the variable vessel vasculitides (VVV). Pathogenetically, a new classification among the so-called mixed-pattern diseases between classical polygenic autoinflammatory disorders and autoimmune diseases is being discussed. The genetic association with HLA-B51 is undisputed and an association with HLA-A26 as well as with polymorphisms in the IL-10 and IL23R-IL12RB2 genes have recently been described. Increasingly, a participation of IL-17 in the pathogenesis of BD is assumed. Therapeutically, the EULAR recommendations are still applicable. Interferon-alpha can be discontinued for severe ocular BD in remission without further relapses. Infliximab can be switched to adalimumab effectively and recent case series show an efficacy of IL-1 antagonists, tocilizumab and rituximab for BD.