New ACR/EULAR SSc Criteria Work Well in Practice

Jordan S, Maurer B, Toniolo M Beat M, Distler O. Performance of the new ACR/EULAR classification criteria for systemic sclerosis in clinical practice.Rheumatology 2015; First published online: March 11, 2015. doi: 10.1093/rheumatology/keu530

New classification criteria for systemic sclerosis from the American College of Rheumatology (ACR) ACR and the European League Against Rheumatism (EULAR) appear be more sensitive and perform better in real-life clinical practice than the 1980 ACR criteria, according to these Swiss researchers.

However, patients missed by the new criteria could still be diagnosed with early/mild SSc, the researchers say.

The study compares the 2013 ACR/EULAR criteria with the old ACR criteria in a cohort of 304 consecutive patients classified as having either established SSc according to the old criteria (n=162) or early/mild SSc not fulfilling the old measures (n=142).

According to the scores for each group, all of the patients with established SSc fulfil the new ACR/EULAR criteria. Among those with mild/early SSc, 56% (n=80) meet the new joint classification criteria and 43.7% (n=62) do not.

Among the early SSc patients missed by the new system, 97.5% have Raynaud’s phenomenon (RP), 88.8% SSc-related antibodies -- anticentromere (ANCA), anti–topoisomerase I (anti–Scl-70, and anti–RNA polymerase III antibodies – and 82.5% show a tell-tale pattern on nailfold capillaroscopy (NFC).

So the sensitivity for ACR/EULAR criteria is 79.66% versus 53.3% for the old set in detecting early/mild SSc, the authors say.

They note that mild and early SSc probably has a different prognosis and clinical course, and despite its increased sensitivity, the new classification system cannot be used as diagnostic criteria set for milder disease.

In fact, patients with RP, SSc-characteristic antibodies, and an SSc pattern of NFC might still be diagnosed with early SSc, even if they don’t fulfil the new ACR/EULAR criteria.