Table 4. Current practice in assessment of ENA testing.
| ENA – screen test (N = 4) |
N (proportion) |
|---|---|
| Method | |
| ELISA | 3 (0.75) |
| FEIA | 1 (0.25) |
| Antigens included: | |
| “Classic” ENA panel: SS-A/Ro60, SS-B/La, U1-RNP, Sm, Scl-70, Jo-1 | 4 (1.0) |
| Classic ENA panel + additional specificities: CENP, Ro52 (TRIM21), RNA-polymerase III, PM-Scl, PCNA, Fibrillarin, Ribosome-P protein, Mi-2) | 1 (0.25) |
| Results reported as: | |
| Qualitative | 3 (0.75) |
| Semiquantitative (ratio) | 1 (0.25) |
| ENA – specific tests (N = 12) |
N (proportion) |
| Method | |
| FEIA | 4 (0.33) |
| ELISA | 3 (0.25) |
| MIA (Luminex) | 3 (0.25) |
| LIA | 1 (0.08) |
| FEIA + LIA | 1 (0.08) |
| Specificities | |
| SS-A/Ro60 | 12 (1.0) |
| Ro52 (TRIM21) | 5 (0.42) |
| SS-B/La | 12 (1.0) |
| U1-RNP | 11 (0.92) |
| RNP70 | 3 (0.25) |
| Sm | 11 (0.92) |
| Scl-70 | 12 (1.0) |
| Jo-1 | 11 (0.92) |
| Ribosome – P protein | 4 (0.33) |
| CENP | 10 (0.83) |
| Histones | 3 (0.25) |
| Nucleosomes | 1 (0.08) |
| ENA = extractible nuclear antibodies. FEIA = Fluorescence enzyme immunoassay. ELISA = Enzyme-linked immunosorbent assay. MIA = Multiplex bead immunoassay. LIA = Line immunoassay. SS-A/Ro60 = Anti-Sjögren’s-syndrome-related antigen A. Ro52 (TRIM21) = Tripartite motif-containing protein 21. SS-B/La = Sjögren syndrome type B antigen. U1-RNP = U1 ribonucleoprotein. PM/Scl = Polymyositis/Scleroderma. PCNA = Pleomorphic cell nuclear antigen. Sm = Smith antigen. Scl-70 = topoisomerase I. Jo-1 = histidyl tRNA synthetase. CENP = antibodies targeting centromere proteins. Mi-2 = myositis specific antibody. | |