Step 1 → Musculoskeletal, Skin, and Connective Tissue Systemic Autoimmunity and Connective TissuePreview this topic sectionPreview the conditions. Plans unlock the full Step 1 details when you need them. Free Biochemistry Free Microbiology Plans Systemic Autoimmunity and Connective Tissue conditions Antiphospholipid Syndrome CREST syndrome Dermatomyositis Diffuse scleroderma IgG4-related Disease Mixed Connective Tissue Disease (MCTD) Polymyositis Raynaud disease Raynaud syndrome Sjögren Syndrome Systemic Lupus Erythematosus (SLE)