Frequency of HLA-DR alleles in familial spondyloarthropathy (SpA) according to specific manifestations*
| Number (%) of patients with SpA | |||||||
|---|---|---|---|---|---|---|---|
| HLA-DR allele | Number (%) of healthy B27+ siblings (n=71) | All/B27+ patients (n=188/185) | Radiographic sacroiliitis† (n=120) | Arthritis (n=89) | Uveitis (n=57) | Psoriasis (n=35) | IBD (n=8) |
| *IBD, inflammatory bowel disease; †radiographic sacroiliitis of at least bilateral grade II or unilateral grade III; ‡B27+ patients v B27+ healthy siblings: p=0.003/pcorr=0.04, using Fisher's exact test; relative risk (95% CI)1 .3 (1.1 to 1.5); §radiographic v no radiographic sacroiliitis: p=0.006/pcorr=0.07, using Fisher's exact test; relative risk (95% CI)=0.6 (0.4 to 0.9). ¶IBD v no IBD: p=0.06/pcorr=0.72, using Fisher's exact test; relative risk (95% CI)=3.8 (1 to 14.4). | |||||||
| DR1 | 24 (34) | 59 (31/32) | 40 (33) | 31 (35) | 19 (33) | 10 (29) | 2 (25) |
| DR2 | 20 (28) | 35/34 (19/18) | 22 (18) | 19 (21) | 11 (19) | 6 (17) | 1 (13) |
| DR3 | 10 (14) | 22/21 (12/11) | 15 (12) | 11 (12) | 9 (16) | 4 (11) | 1 (13) |
| DR4 | 11 (15) | 63 (34)‡ | 42 (35) | 26 (29) | 15 (26) | 13 (37) | 1 (13) |
| DR7 | 9 (13) | 32 (17) | 22 (18) | 17 (19) | 11 (19) | 7 (20) | 1 (13) |
| DR8 | 4 (6) | 18 (10) | 15 (12) | 6 (7) | 7 (12) | 3 (9) | 1(13) |
| DR9 | 1 (1) | 2 (1) | 2 (2) | 2 (2) | 1 (2) | 1 (3) | 0 (0) |
| DR10 | 1 (1) | 2 (1) | 1 (0.8) | 1 (1) | 0 (0) | 1 (3) | 0 (0) |
| DR11 | 27 (38) | 54/53 (29) | 31 (26) | 22 (25) | 16 (28) | 8 (23) | 3 (38) |
| DR12 | 0 (0) | 4 (2) | 2 (2) | 1 (1) | 0 (0) | 2 (6) | 0 (0) |
| DR13 | 15 (21) | 35/32 (19/17) | 15 (12)§ | 18 (20) | 12 (21) | 3 (9) | 4 (50)¶ |
| DR14 | 7 (10) | 25 (13/14) | 19 (16) | 12 (13) | 9 (16) | 8 (23) | 0 (0) |