Table 1.
Characteristics of patients with GPA and healthy controls
| HC | GPA, no future relapse | GPA, future relapse | |
|---|---|---|---|
| Subjects, n (% male) | 13 (46) | 13 (46) | 13 (46) |
| Age, years, mean (range) | 55 (44–74) | 52 (32–76) | 52 (32–75) |
| PR3-ANCA titer, median (range) | 1:40 (0 to >640) | 1:80 (20 to >640) | |
| Disease duration, years, median (range) | 12.6 (5.5–31.5) | 15.3 (2.3–24.3) | |
| Number of previous relapses, median (range) | 2 (0–5) | 5 (1–10) | |
| Time to relapse after sample, days, median (range) | n/a | 74 (14–157) | |
| Disease form, n (%) | |||
| Localized | 0 (0) | 0 (0) | |
| Early systemic | 2 (15.4) | 2 (15.4) | |
| Generalized | 8 (61.5) | 9 (69.2) | |
| Severe | 3 (23.1) | 2 (15.4) | |
| Treatment at time of sampling, n (%) | |||
| Aza | 1 (7.7) | 3 (23.1) | |
| Pred | 1 (7.7) | 1 (7.7) | |
| MMF + pred | 2 (15.4) | 3 (23.1) | |
| No immunosuppressive therapy | 9 (69.2) | 6 (46.2) | |
| B cell phenotype in %, median (range) | |||
| Total CD19+ B cells | 12.3 (6.6–22.24) | 9.8 (6.3–28.6) | 9.9 (3.4–19.9) |
| Transitional B cells | 10.77 (3.9–17.6) | 9.2 (4.8–18.1) | 9.3 (3.1–11.7) |
| Naive B cells | 63.6 (37.4–83.4) | 79.0 (74.5–90.1) | 79.3 (60.1–85.7) |
| Memory B cells | 22.4 (6.6–54.0) | 8.1 (4.2–29.7) | 8.2 (2.3–19.5) |
| CD24highCD38high B cells | 6.6 (2.2–9.6) | 4.6 (2.1–11.8) | 5.3 (0.9–8.5) |
| CD24highCD27+ B cells | 15.5 (3.5–45.4) | 3.3 (2.1–24.8) | 3.4 (0.7–10.8) |
| CD5+ B cells | 23.4 (12.1–57.6) | 19.8 (12.1–64.2) | 18.9 (4.7–49.9) |
ANCA anti-neutrophil cytoplasmic antibody, Aza azathioprine, GPA granulomatosis with polyangiitis, HC healthy controls, MMF mycophenolate mofetil, n/a not applicable, PR3 proteinase-3, Pred prednisolone