Table 1.
Baseline characteristics
| HC (n = 22) | iSLE (n = 29) | SLE (n = 39) | p value | |
|---|---|---|---|---|
| Female gender, n (%) | 18 (82) | 23 (79) | 32 (82) | NS |
| Age (years) | 45 (24–65) | 44 (20–83) | 43 (19–76) | NS |
| Race, n (%) | ||||
| Caucasian | 100 | 25 (86) | 35 (90) | |
| Asian | 0 | 2 (7) | 1 (3) | |
| Other | 0 | 2 (7) | 3 (8) | |
| Disease duration (years) | 1.4 (0.1–4.6) | 2.8 (0.5–6.8) | 0.004 | |
| ACR criteria | 3 (1–3) | 5 (2–9) | < 0.0001 | |
| SLICC criteria | 3 (2–4)* | 5 (3–9) | < 0.0001 | |
| Clinical criteria, n (%) | ||||
| Skin involvement | 13 (45) | 21 (54) | 0.46 | |
| Photosensitivity | 3 (10) | 9 (23) | 0.17 | |
| Arthritis | 6 (21) | 18 (46) | 0.03 | |
| Alopecia | 0 | 5 (13) | 0.05 | |
| Ulcera | 1 (3) | 6 (15) | 0.11 | |
| Hematologic | 11 (38) | 26 (67) | 0.02 | |
| Serositis | 2 (7) | 9 (23) | 0.07 | |
| Renal | 0 | 13 (33) | 0.001 | |
| Neurologic | 1 (3)** | 2 (5) | 0.48 | |
| Immunologic criteria, n (%) | ||||
| ANA | 3 (14) | 29 (100) | 39 (100) | NA |
| Anti-dsDNA | 0 | 9 (31) | 32 (82) | < 0.0001 |
| Anti-SSA | 0 | 13 (45) | 13 (33) | 0.59 |
| Anti-Smith | 0 | 2 (7) | 6 (15) | 0.28 |
| Decreased complement | 2 (9) | 4 (14) | 25 (64) | < 0.0001 |
| Antiphospholipid Ab | 0 | 7 (24) | 17 (44) | 0.01 |
| Coombs positive | NA | 4/23 (17) | 7/17 (41) | 0.10 |
*One patient had 4 immunologic SLICC criteria, but no clinical criterion
**Small fiber neuropathy not otherwise explained
For continuous data, median (range) are shown. p values of nominal variables are calculated for comparison of iSLE and SLE using chi-square test and continuous variables by using Mann-Whitney U test. p values < 0.05 are indicated by italic font
Abbreviations: ANA antinuclear antibody, anti-dsDNA anti-double-stranded DNA, Ab antibodies, NS non-significant, NA not available