Mixed connective tissue disease
- See also: Scleroderma
First described in 1972,  often called distinct rheumatologic disease, mixed connective tissue disease (MCTD) is variously considered an overlap (i.e., overlap connective tissue disease) between systemic lupus erythematosus (SLE), scleroderma, and polymyositis; a specific subset of scleroderma with objective features of other diseases, such as SLE or polymyositis; or a distinct disease entity.  In Medical Subject Headings, it is termed "A syndrome with overlapping clinical features of systemic lupus erythematosus, scleroderma, polymyositis, and Raynaud's phenomenon. The disease is differentially characterized by high serum titers of antibodies to ribonuclease-sensitive extractable (saline soluble) nuclear antigen and a "speckled" epidermal nuclear staining pattern on direct immunofluorescence." 
- Sharp GC; Irvin WS; Tan EM; Gould RG; Holman HR (1972), "Mixed connective tissue disease--an apparently distinct rheumatic disease syndrome associated with a specific antibody to an extractable nuclear antigen (ENA).", Am J Med 52 (2)
- Fredrick M Wigley and Laura K Hummers (2004), Chapter 35: Clinical features of systemic sclerosis, Practical Rheumatology (Third ed.), Mosby, ISBN 03230299396, p. 450
- Anonymous (2020), Mixed connective tissue disease (English). Medical Subject Headings. U.S. National Library of Medicine.
- Robert W Hoffman and Eric L Greidinger (7 August 2008), "Mixed Connective-Tissue Disease: Overview", eMedicine Specialties > Rheumatology > Systemic Rheumatic Disease
- Christopher-Stein L, Wigley F, "(Letter) Tumor Necrosis Factor-a Antagonists Induce Lupus-like Syndrome in Patients with Scleroderma Overlap/Mixed Connective Tissue Disease", J Rheumatol