TITLE:
A Multiplex Autoantibody Panel for Early Detection of Autoimmune Disease Activity
AUTHORS:
Yuanyuan Yang, Karthik Krishna, Vinodh Ranganathan, Vasanth Jayaraman, Tianhao Wang, Kang Bei, Hari Krishnamurthy, John J. Rajasekaran
KEYWORDS:
Autoantibody, ANA, ENA, Autoimmunity, Connective Tissue Disorder
JOURNAL NAME:
Open Journal of Rheumatology and Autoimmune Diseases,
Vol.8 No.2,
May
9,
2018
ABSTRACT: Background: Detection of autoantibodies has played a consolidate
role in diagnosis of systemic autoimmune disorders. A cascade autoantibody
testing is usually performed by employing antinuclear antibodies (ANA) test as
a first screening test and the other tests as second level determinations.
Here, we present that supplementing extractable nuclear antigens (ENA) tests to
the ANA test may capture more autoimmunity and provide critical medical
information at an early stage. In this study, weevaluated the clinical significance of a multiplex ANA + ENA panel. Methods: A cohort of 110 subjects,
identified as ANA negative but ENA positive, were followed up for two years.
The detection of their ANA and anti-ENA autoantibodies was assessed with a multiplex ANA + ENA panel at Vibrant America Clinical Laboratory. Results: During two years of multi-visit follow-up, 23 out of 110 subjects
(20.9%) were found to become ANA positive within an average of 385 (±144) days.
Histone (50/110, 45.5%) and Chromatin (25/110, 22.7%) antibodies were the most
frequently found antibodies at their first visits. The subjects who were
positive for RNP (5/8, 62.5%) and SSA (Ro) (10/22, 45.5%) have the highest
ratio of conversion to positive ANA. No significant correlation was observed
between the conversion frequency and the number of anti-ENA antibodies being
carried. Conclusion: This study, which followed up on the subjects who
had disparate ANA and ENA test results, showed that anti-ENA antibodies may
exist years earlier than ANA. Combining ENA tests with ANA screening may reduce
false negatives and improve sensitivity.