The road to early diagnosis of systemic sclerosis : the evolution of diagnostic and classification criteria in the past decades

Increasing knowledge about the rare disease systemic sclerosis (SSc) and improved diagnostic methods in recent decades has led to the possibility of diagnosing systemic sclerosis in earlier disease stages. In this review, we describe the evolution of diagnostic and classification criteria for SSc, beginning with the preliminary ARA criteria for the classification of SSc in 1980, then presenting the criteria for limited and diffuse cutaneous SSc by LeRoy et al. in 1988 and 2001, and finishing with a discussion of the recently published new ACR-EULAR classification criteria in 2013. In addition, we seize the ongoing discussion about the intermediate subtype of SSc and highlight whether the two special subtypes CREST syndrome as well as SSc sine scleroderma are similar or different from the limited cutaneous SSc subtype. Finally, we address the question when a patient should be referred to the rheumatologist and discuss potential red flags for early diagnosis of systemic sclerosis.