Chapel Hill nomenclature for WG and MPA as applied to the multicenter cohort of 240 patients with WG and 78 patients with MPA.
| Criteria | No. Patients Fulfilling Criteria | Accuracy, % | |
|---|---|---|---|
| WG, n (%) | MPA, n (%) | ||
| Mandatory criteria for WG | |||
| Granulomatous inflammation involving the respiratory tract | 56 (23.3) | 0 (0) | 42.1 |
| Including patients fulfilling surrogate measurements of granulomatous inflammation (respiratory tract) | 231 (96.3) | 8 (10.3) | 94.7 |
| Necrotizing vasculitis affecting small to medium-size vessels | 95 (39.6) | 31 (39.7) | 44.7 |
| Including patients fulfilling surrogate measurements of necrotizing vasculitis (small to medium-size vessels) | 214 (89.2) | 70 (89.7) | 69.8 |
| Patients classified as WG without surrogate measurements | 32 (13.3) | 0 (0) | 35.0 |
| Patients classified as WG including surrogate measurements | 206 (85.8) | 8 (10.3) | 86.8 |
| Mandatory criteria for MPA | |||
| Necrotizing vasculitis with few or no immune deposits affecting small to medium-size vessels | 95 (39.6) | 31 (39.7) | 55.3 |
| Including patients fulfilling surrogate measurements of necrotizing vasculitis (small to medium-size vessels) | 214 (89.2) | 70 (89.7) | 30.2 |
| Patients classified as MPA without surrogate measurements | 95 (39.6) | 31 (39.7) | 55.3 |
| Patients classified as MPA including surrogate measurements | 214 (89.2) | 70 (89.7) | 30.2 |
| Optional criteria for both WG and MPA | |||
| Necrotizing glomerulonephritis | 118 (49.2) | 60 (76.9) | 42.8* |
| Including patients fulfilling surrogate measurements of glomerulonephritis | 163 (67.9) | 74 (94.9) | 44.2† |
| Association with ANCA | 183 (90.2) of 203 cases | 56 (84.9) of 66 cases | 71.7†† |
| Additional optional criteria for MPA only | |||
| Necrotizing arteritis in small to medium-size arteries | No data | No data | — |
| Pulmonary capillaritis | 23 (9.6) | 0 (0) | 68.2 |
| Including patients fulfilling surrogate measurements of pulmonary capillaritis | 88 (36.7) | 21 (26.9) | 54.4 |