AB0668 CLINICAL CHARACTERISTICS OF RADIOGRAPHIC AND NON RADIOGRAPHIC AXIAL SPONDYLOARTHRITIS IN A GROUP OF TUNISIAN SPONDYLOARTHRITIS

Abstract

Background:In the literature, non radiographic axial Spondyloarthritis (nr-SpA) is predominantly female with a shorter period of evolution and similar peripheral manifestations to radiographic axial spondyloarthritis (r-SpA). However, we do not have Tunisian studies comparing the two groups of axial spondyloarthritis (ax-SpA).Objectives:The aim of this study was to assess the epidemiological and clinical differences between nr-SpA and r-SpA in a group of Tunisian ax-SpA.Methods:Two hundred patients with ax-SpA (ASAS 2009 criteria) were retrospectively included and classified as r-Spa characterized by the presence of radiographic sacroiliitis and nr-SpA defined by the presence sacroiliitis only on MRI or HLA B27 antigen with other clinical features. The different demographic and clinical parameters were compared between the nr-SpA and r-SpA groups.Results:One hundred thirty-eight men and 62 women were included with a sex ratio of 2,2. The mean age was 43,3 ± 11,2 years and the mean period of evolution was 10,7 ± 8,4 years. The patients were divided to r-SpA in 80% of cases (n = 160) and nr-SpA in 20% of cases (n = 40).Women were more present in the nr-SpA group with 47,5% of women versus 26.8% of women in the r-SpA group (p = 0,01). The patients with nr-SpA were younger with a mean age of 39,4 ± 13,4 years versus 44,3 ± 10,4 years in patients with r-SpA (p = 0,03). The mean period of evolution was shorter in nr-SpA group (5,8 ± 4,9 years vs 11.9 ± 8.5; p <0.001). The family history of SpA was more frequent in nr-SpA group (17.5% vs 4.3%, p = 0.004). Arthritis were more frequent in nr-SpA (42.5% vs 13.7%; p <0.0001). Similarly, enthesitis were more frequent in nr-SpA group (45% vs 15.6%; p <0.0001).No statistically significant differences were found in the following parameters: age at onset of symptoms, diagnostic delay, HLA B-27 antigen and dactylitis.Conclusion:The clinical features were different in the 2 groups of ax-SpA: Patients with nr-SpA were more female and had more peripheral manifestations while patients with r-SpA were older and with longer period of evolution.