Background Viral infections can cause inflammatory joint manifestations. Wide series regarding B19 Parvovirus have been published, but the arthritis secondary to Epstein - Barr virus (A-EBV), however, is infrequent and usually presents with multiple joint involvement during a systemic infection.

Objectives To describe the epidemiological characteristics, clinical presentation and evolution of a series of patients with A-EBV.

Methods Descriptive study of A-EBV cases diagnosed in our hospital in a 6-month period. In all cases, serological demonstration of EBV-IgM allowed us to confirm a recent viral infection. Clinical notes were reviewed to collect data in the virus presentation.

Results Case 1: 27-year old woman with a 3-week history of progressive and asymmetrical oligoarthritis involving small joints and high levels of acute phase reactants. Treated with NSAIDs and corticosteroids. Clinical resolution within 3 months, with EBV-IgM clearance. Case 2: 54-year old woman with a 3-week history of progressive and symmetrical small joint polyarthritis. Treated with NSAIDs and corticosteroids. Persistence of symptoms, without EBV-IgM clearance, in spite of DMARD introduction. Case3: 32-year old woman with a 2-month history of progressive and symmetrical small joint polyarthritis, in association with a flu-like syndrome. Needed DMARDs because of the persistence of symptoms. EBV-IgM clearance within 5 months. Case 4: 37-year old woman with a 5-day evolution inflammatory polyarthralgia, associated with erythema, hypertransaminasemia and elevated acute phase reactants. Clinical resolution within 2 weeks. Awaiting check on EBV-IgM clearance.

Conclusions A-EBV seems to affect young women preferably, with a seasonal predominance. It is not infrequent to find chronicity, which is associated with delay in specialist attendance. Given the possible relationship between Epstein-Barr virus and Rheumatoid Arthritis, we should not delay a DMARD treatment in those patients who develop chronic disease.

Disclosure of Interest None Declared