Published: 25 September 2026
Author(s): Kevin Chevalier, Marie-Elise Truchetet, Cloé Comarmond, Jeska de Vries-Bouwstra, Voon Ong, Paola Triggianese, Diana Marinello, Marta Mosca, Silvia Bellando Randone, Sergio Prieto-González, Zana Brkic, Vera Guimarães, Magdalena Ciupera, Marzena Olesinska, Luc Mouthon, Benjamin Chaigne, on behalf of the European Federation of Internal Medicine Diseases Systemic Autoimmune Diseases working group and the European Reference Network on Rare and Complex Connective Tissue and Musculoskeletal Mixed connective tissue group
Section: Original Article
Mixed connective tissue disease (MCTD) is a rare systemic autoimmune disorder defined by the co-occurrence of clinical features overlapping with other connective tissue diseases (CTD) such as systemic lupus erythematosus (SLE), systemic sclerosis (SSc) or idiopathic inflammatory myopathies, together with the presence of high-titre anti-U1 ribonucleoprotein (anti-U1RNP) antibodies [1].
