SAT0404 Clinical characteristics and outcome after treatment of a national cohort of pcr-positive lyme arthritis
Authors: M. Scherlinger, A. Grillon, J. Sibilia, L. Arnaud, B. Jaulhac
Journal: Annals of the Rheumatic Diseases (2018)

<h3>Background</h3> Lyme arthritis (LA) is a disseminated <i>Borrelia</i> infection whom prevalence is lower in Europe than in the USA, probably because of difference in <i>Borrelia</i> species ecology. Few data concerning treatment efficacy and long-term outcome of LA in Europe are available. <h3>Objectives</h3> The aim of our study was to describe clinical characteristics and treatment outcomes of a national cohort of patients with LA confirmed with synovial fluid PCR. <h3>Methods</h3> We conducted a retrospective observational study using the French Borrelia reference centre database. Patients presenting with a PCR positive for <i>Borrelia</i> DNA in their synovial fluid between 2011 and 2016 were included. PCR-positive patients were offered by their referring physician to participate to a standardised telephonic interview. Patients' medical files were also retrieved. The main objectives were to describe patient characteristics, disease presentation and outcomes after antibiotic treatment. <h3>Results</h3> Between 2011 and 2016, among 358 synovial fluids tested at the national reference centre, 38 were positive for <i>Borrelia</i> DNA. Among these patients, 35 were contacted (3 missing contact information). Median age was 36 years with 31% minors and 63% men. Tick exposure was reported by 88% patients whereas tick bite and erythema migrans were only reported in 40% (10/25) and 14% (3/21), respectively. The presentation was monoarticular in 91% (32/35) cases and oligoarticular in others. The knee was involved in 97% (34/35) cases and 21% presented fever. The diagnosis was often delayed with a median time from symtom onset to diagnosis of 3 months (range 1 to 112). The serology performed before or at the time of the PCR testing was IgG positive in all cases but only in IgM positive in 40%. All positive IgG serologies were also positive with Western-Blot. In the synovial fluid, the identified species of Borrelia were <i>B. burgdorferi sensu stricto</i>, <i>B. garinii</i> and <i>B. afzelii</i> in 54%, 29% et 17% of cases, respectively. Antibiotics prescribed were mostly doxycycline and ceftriaxone in 17 and 9 patients, respectively, sometime in combination. Follow-up data were available for 26 patients with a median follow-up time of 27 months (range 1–73). Full recovery was reported by 62% patients whereas 6 presented persistent non-inflammatory articular pain of the affected joint. One patient reported a chronic pain syndrome without objective sign of persistent infection (including a negative synovial fluid PCR). Three patients developed chronic inflammatory arthritis leading to the introduction of DMARDs. <h3>Conclusions</h3> Our study reports original data on Lyme arthritis in France. Treatment outcomes are usually good but a significant proportion of patients may develop chronic inflammatory arthritis. <h3>Acknowledgements</h3> All clinicians participating the study. <h3>Disclosure of Interest</h3> None declared