One year in review 2019: Behçet's syndrome.

Several epidemiologic studies report on the prevalence of Behçet's syndrome (BS) and demographic and clinical findings in patients from different countries and ethnicities. Although these studies point out geographic differences in disease course, methodologic differences make it difficult to compare the results of these studies. Recent data suggest that neutrophil extracellular trap levels are elevated in patients with BS, and that it may be a potential therapeutic target for the reduction or prevention of BS-associated thrombotic risk. Details on the mode of functioning of ERAP have been delineated and further epigenetic data reported. Wall thickness of lower extremity veins is increased among BS patients without any apparent clinical involvement. Magnetic resonance (MR) venography and Doppler ultrasonography (USG) were comparable in the diagnosis of chronic deep vein thrombosis, while MR venography is more effective in detecting collateral formations. Results were also collected on some dietary and non-dietary factors in triggering oral ulcers, while smoking seems to have a protective role. With regards to the therapy, it has been demonstrated that endovascular interventions carry the risk of inducing pathergy phenomenon. Apremilast has been convincingly shown to be useful for oral ulcers of BS and classical immunosuppressives are effective as first line therapy in more than half of patients with uveitis. While infliximab and adalimumab seem to be equally effective in the treatment of refractory uveitis of BS, the combination of adalimumab and immunosuppressives appears to be superior to immunosuppressives alone for venous thrombosis of the extremities. In addition, tocilizumab might be an alternative to anti-TNF agents for patients with arterial involvement refractory to immunosuppressives. On the other hand, the place of IL-17 inhibition in the treatment of BS still remains questionable.