Validation of the ACR/EULAR classification criteria for systemic sclerosis in patients with early scleroderma.
Rheumatol Int 2017 Aug 17. Epub 2017 Aug 17.
Rheumatology Division, Escola Paulista de Medicina, Universidade Federal de São Paulo, Rua Botucatu 740, 3º andar, São Paulo, SP, 04023-062, Brazil.
The aim of this study was to validate the 2013 ACR/EULAR classification criteria for systemic sclerosis (SSc) in patients with SSc, including patients with early SSc. Fifty-six consecutive patients with early SSc (2001 LeRoy and Medsger criteria), 122 patients with established SSc (1980 ACR classification criteria), and 141 patients with SSc-like disorders were included in this cross-sectional study. The diagnostic performance of the 2013 ACR/EULAR criteria was compared with the 1980 ACR criteria in several subsets of patients. The performance of individual variables was also obtained. Receiver operating characteristic (ROC) curves and optimal cut-off values were computed. The sensitivity and specificity in the whole cohort of 178 SSc patients were 77.6 and 98.5%, respectively, using the 2013 ACR/EULAR criteria and 68.5 and 100%, respectively, using the 1980 ACR criteria. Twenty-eight percent of the patients with early SSc met the 2013 ACR/EULAR criteria. Among the patients with early SSc, 53% of those who had Raynaud's phenomenon, abnormal capillaroscopy and positive SSc-related antibodies met the 2013 ACR/EULAR criteria. The area under the ROC curve was 0.975 (95% confidence interval 0.962-0.987). The best cut-off value for the total score was ≥8 (sensitivity 82%; specificity 97.9%). The individual variables with the highest specificity values were proximal skin thickening, sclerodactyly (specificity 100%), telangiectasia and SSc-related antibodies (specificity 98.6%). Raynaud's phenomenon had the best sensitivity (99.4%) but had low specificity (4.2%). In conclusion, the 2013 ACR/EULAR classification criteria showed high accuracy and increased sensitivity in the classification of patients with early SSc.