Antibodies against Yersinia, Campylobacter, Salmonella, and Chlamydia in patients with Behçet's disease

Infection and vasculitis

Vasculitis may be associated with infection, immunization or anti-microbial drugs. Infections are responsible for a number of different types of vasculitis. Conversely, patients with vasculitis may develop infections, which sometimes mimic relapse. The aim of this review is to summarize the various aspects of the inter-relationship between vasculitis and infection, and the physiopathological mechanisms involved, in light of our current knowledge from animal models. Currently, a causal relationship between infection and vasculitis has only been established in a few instances and many mechanisms remain hypothetical. This inter-relationship is further assessed from the point of view of clinical presentation and therapeutic options, based on case reports and prospective observational data.

Incidence of Yersinia enterocolitica antibodies in patients with inflammatory joint diseases

Agglutinating antibodies against Yersinia enterocolitica serotypes 0:3, 0:8 and, to a minor extent, 0:6 were found in 18 out of 93 patients with inflammatory joint diseases. Patients with undifferentiated arthritis showed the highest prevalence of antibodies against Yersinia enterocolitica. The possibility that serotypes other than 0:3 may be involved in triggering arthritis is discussed.

The role of infectious agents in the spondylarthropathies

The clinical similarities of the spondylarthropathies and their frequent association with both HLA B27 and microbial infections suggest common pathogenetic mechanisms. The latter may include deposition of immune complexes containing bacterial antigens. or cross-reactivity of such antigens with host target tissue or responding cell antigens. Enteric bacteria, chlamydia and mycoplasma are all candidate etiologic agents, but proof is difficult because they are often found as normal flora, although only genetically susceptible individuals may acquire disease, and many patients have been treated with antibiotics before they can be studied. Nonetheless, a role for endogenous bacteria in reactive arthritis at least seems certain, and should stimulate further investigation into similar pathogenetic mechanisms in other chronic arthritides.