PRTN3 and interstitial lung disease: Although ILD affected 82% of the patients in both groups, ASS patients with ACPA tended to display higher FVC (68.11 ± 22.37 vs 79.50 ± 20.67) and had higher DLCO compared with the ACPA-negative group (50.78 ± 21.98 vs 69.58 ± 18.73, P = 0.046).