Reactive arthritis is a disease closely related to the presence of the HLA-B27 antigen and characterized by sterile joint inflammation secondary to infection. Arthritis is only one of the clinical manifestations of this systemic disease. Its diagnosis rests on history, clinical examination and various serologies. The prognosis is generally good, but recurrences are frequent, in particular in HLA-B27 positive patients. Treatment is mainly symptomatic, and antibiotics should be prescribed only in the event of an active infection. A 3 months course of antibiotics could be beneficial on the long-term evolution in HLA-B27 positive patients, but this practice deserves to be confirmed by additional randomized controlled studies.