Application of Immunoblot assay (ANA 23 Profile) for detection of autoantibodies in systemic sclerosis

Abstract

Objective: Examine the clinical and subclinical characteristics and the rate of autoantibodies in systemic sclerosis (SSc) using Immunoblot  technique (ANA 23 Profile). Research subjects and methods: Cross-sectional descriptive study of 57 patients diagnosed with SSc according to the 2013 American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) criteria and were tested for autoantibodies using the
Immunoblot technique (ANA 23 Profile) at the National Hospital of Dermatology and Venereology. Results: Among 57 SSc patients, the female/male ratio was 5/1. The average age of disease onset was 49.3±13.3, with 57.9% of patients over the age of 50. Diffuse SSc was the most common (70%). Raynaud was the most common symptom (98.2%), followed by gastroesophageal reflux (86%), and pulmonary fibrosis (70.2%). Heart and kidney damage were less frequently observed, accounting for 15.8 and 5.3%, respectively. Positive rates of the three major antibodies in SSc included anti-Scl-70 antibody (63.2%), anti-centromere antibody (17.5%), and anti-RNA polymer III antibody (12.3%), respectively. Scl-70 autoantibodies were mainly found in diffuse skin types (91.7%) while CENP autoantibodies were mainly found in localised skin types (90%) with p<0.05. RNAP III antibodies were mainly found in diffuse skin types (85.7%), however, this difference was not statistically significant (p>0.05). Conclusion: The presence of Scl-70 was related to the diffuse skin types while the presence of CENP was related to localised skin types.