Table 1.
Patient characteristics at the time of renal biopsy
| Demographic data | ANCA-positive group (n = 32) |
ANCA-negative group (n = 222) |
|---|---|---|
| Median age (range) at biopsy, yr | 37.5 (16–78) | 34 (16–75) |
| Median (range) duration of LN, yr | 0 (0–24) | 0.1 (0–28) |
| Sex (M:F) | 1:4 | 1:3.5 |
| Ethnicity, % | White: 25 | White: 30.6 |
| Asian: 31.2 | Asian: 25.7 | |
| Black: 34.4 | Black: 27.5 | |
| Other: 9.3 | Other: 16.3 | |
| ANCA serology, % | MPO: 82 | |
| PR3: 7 | ||
| MPO and PR3: 11 | ||
| Reason for biopsy, % | First presentation: 56 | First presentation: 48 |
| Flare: 34 | Flare: 35 | |
| Failure to respond: 9 | Failure to respond: 8 | |
| Routine: 0 | Routine: 9 |
ANCA, antineutrophil cytoplasmic antibody; F, female; LN, lupus nephritis; M, male; MPO, myeloperoxidase; PR3, proteinase 3.
No significant difference between the 2 patient groups for all parameters shown.