Abstract
Introduction The recognition that patients with ILD and features of autoimmunity constitute a distinct clinical entity (interstitial pneumonitis with autoimmune features – IPAF) highlights the potential need for systematic rheumatology evaluation of these patients, but relevant data is scarce.
Aims To evaluate patterns of referral to rheumatology in ILD patients with autoimmune features, and to compare rheumatology diagnosis with MDD consensus diagnosis.
Methods We studied patients referred to our ILD center between 2010 and 2015. Patients with at least one positive serum antibody (AB) and/or one autoimmune symptoms were included. Rheumatology diagnosis and MDD diagnosis (performed after rheumatology evaluation) were compared. Four pre-specified groups were defined: isolated ANA titer ≤1/320, positive ENA screen, positive myositis panel (MP) AB, and clinical autoimmune features without AB.
Results Of 113 patients, 106 were referred to rheumatology (94%), where final diagnoses were: presence of CTD (25%), absence of CTD (57%) and IPAF (19%). Concordance with MDD diagnoses was 96%, 88%, and 76% respectively. Overall Kappa coefficient of agreement was 0.89 (95% CI 0.81-0.97, p=0.04). Similarly, agreement was 92% and 88% in patients with positive ENA (n=36) and MP antibodies (n=50). For patients with isolated ANA (n=12) or isolated symptoms without AB (n=3), there were no diagnoses of CTD and agreement with MDD was 100%.
Conclusion In our center, the rate of referral to rheumatology of patients with even minor autoimmune features was high. Rheumatology diagnosis was rarely overturned by MDD, including for patients with IPAF, suggesting an important contribution of this evaluation to final diagnosis.
- Copyright ©the authors 2016
