White patients and patients who did not have an identified myositis autoantibody were more likely to have a documented infection within 6 months before illness onset than those from other racial groups or those with the anti-p155 autoantibody (P = 0.0008; OR 2.7; 95% CI 1.5, 4.8 and www.rheumatology.oxfordjournals.org None 114 (40) 62 (41) 52 (38) 69 (35) 45 (52) 15 (32) 31 (48) 49 (42) 20 (46) 19 (36) No. of patients exposed (22) 8 (25) 10 (30) 15 (22) 8 (34) 8 (24) 3-5 20 (12) 5 (6) (12) 4 (10) 2 (7) 1 (3) 12 (18) 2 (8) 2 (6) (18) 27 (17) 35 (20) 48 (18) 14 (20) 11 (19) 13 (22) 26 (18) 15 (33) zz