Prevalence and clinical association of the presence of anti-neutrophilic cytoplasmic antibody in systemic sclerosis

Abstract

Introduction: Anti-neutrophilic cytoplasmic antibody (ANCA) has been reported in systemic sclerosis (SSc). Some clinical features of SSc can also be presented with ANCA-associated vasculitis. Objectives were to determine the prevalence and clinical associations with ANCA among Thais with SSc. Material and methods: A cross-sectional study of Thai adult SSc patients was conducted. According to the sample size calculation, 185 patients were included. Clinical and laboratory tests for serology and others for evaluation of the clinical association with ANCA were done simultaneously on the study date. Results: The female to male ratio was 2 : 1. The majority had the diffuse SSc subset (71.2%). The respective prevalence of having a) at least 1 serological test for ANCA (viz., perinuclear ANCA, cytoplasmic ANCA, anti-myeloperoxidase, or anti-proteinase3), b) positive for either p-ANCA or c-ANCA, c) positive for either anti-MPO or anti-PR3, d) p-ANCA and anti-MPO and e) c-ANCA and anti-PR3 was 21.6% (95% CI: 15.9-28.3), 11.9% (95% CI: 7.6-17.4) and 13.0% (95% CI: 8.5-18.7) and 1% (95% CI: 0.1-3.9). By multivariate analysis, the erythrocyte sedimentation rate elevation was significantly associated with the presence of the antibody (OR = 11.36, 95% CI: 1.44-83.65), while elevation of high sensitivity cardiac troponin-T (hs-cTnT) was significantly associated with the presence of either p-ANCA or c-ANCA (OR = 4.25, 95% CI: 1.41-15.34). None of the patients had clinical features of systemic vasculitis. Conclusions: Around one-fifth of SSc patients have detectible ANCA without any features of vasculitis. The presence of ANCA is associated with inflammation and myocardial injury. ANCA is not antibody specific for vasculitis in SSc.

Incidence of Systemic Vasculitis and Clinical Outcomes in Systemic Sclerosis: 2-Years Follow-Up of Asymptomatic Positive for Anti-Neutrophilic Cytoplasmic Antibody

“…In SSc, the prevalence of ANCA-positive using either method was approximately around 12–22%. 10 , 31 However, SSc overlap AAV is quite rare. In a large cohort study of 2200 SSc, the SSc overlap with AAV was 1.6%.…”

“…We included patients ≥ 18 years of age, diagnosed as SSc, and all of them participated in a previous cross-sectional study on the “Prevalence and clinical association of the presence of anti-neutrophilic cytoplasmic antibody in systemic sclerosis”. 10 …”

“…We included patients ≥ 18 years of age, diagnosed as SSc, and all of them participated in a previous cross-sectional study on the "Prevalence and clinical association of the presence of anti-neutrophilic cytoplasmic antibody in systemic sclerosis". 10 The data included SSc clinical features, clinical features of vasculitis, routine laboratory tests for SSc, related laboratory tests for AAV, medical treatment, and outcomes. Data collection started 2 years and later from the date of initial ANCA testing.…”

“…8,9 The prevalence of asymptomatic positive for ANCA in SSc is around 22%. 10 Notwithstanding, the clinical relevance and outcomes of patients that are asymptomatic positive for ANCA are uncertain. We thus aimed to evaluate the incidence of AAV and the clinical outcomes after 2 years of follow-up in SSc patients who were asymptomatic positive for ANCA after screening.…”