Background The anti-saccharomyces cerevisiae antibodies (ASCA) are serum markers in inflammatory bowel disease (IBD) either Crohn’s disease (CD) or ulcerative colitis (UC), which are present in almost 50% patients with CD. In spondylarthritis (SpA), there is a lack of specific markers to help the clinician for the diagnosis and management of the disease. ASCA, often the IgA form, are found in 30% patients who have SpA even without any digestives symptoms.
Objectives We performed in our department a cross-sectional study evaluating the prevalence and the influence of the ASCA status on disease phenotype.
Methods 223 SpA patients (all fulfilling the ESSG criteria) were included. Demographic (age, gender, disease duration), clinical (axial and/or peripheral presentation, presence of arthritis, enthesitis, spine pain, psoriasis, uveitis, IBD), biological (HLAB27 status) data, and use of treatments (DMARDs, anti-inflammatory drugs and anti-TNFa) were collected. For each patient, ASCA determination was performed by serum indirect immunofluorescence. Demographic characteristics, clinical features and blood tests of SpA patients ASCA positive and negative were compared.
Results 223 SpA patients (mean age: 46.7±14.4 years, 54.3% men, 55% HLAB27+) were included. The mean disease duration was 105.7±116.9 months. 86% of patients had axial involvement, 70.4% had peripheral involvement. 10.6% suffered of IBD. 20.6%, 22.9% and 61.2% of patients received anti-inflammatory drugs, DMARDs or anti-TNFa respectively. Among the 223 SpA patients included, positivity of ASCA was observed in 24.7% (n= 55) (IgG: 9.4%; IgA: 21.1%).
The positivity of ASCA was associated with lower frequency of HLAB27 positivity (60.4% vs 38.3%, P = 0.011) and axial involvement (91.1% vs 69.9%, P < 0.0001). Moreover, ASCA positivity was more frequently observed in patients with isolated peripheral involvement (10.7% vs 30.9%, P = 0.001), arthritis (27.3% vs 59.3%, P < 0.0001) and dactylitis (9.8% vs 26.9%, P = 0.004). There was no difference between ASCA+ and ASCA- SpA patients regarding the presence of uveitis, IBD, enthesitis and psoriasis.
Conclusions These findings suggest that ASCA could influence the phenotype of SpA, the ASCA positive status being associated with peripheral involvement, including dactylitis, and a decrease of frequency of HLA B27 antigen.
Disclosure of Interest None Declared