Info
mixed connective tissue disease
Definition (Best Pract Res Clin Rheumatol 2016;30:95)
- Features of SLE, systemic sclerosis, and/or polymyositis that appear gradually over years and often evolve to a dominant phenotype of SLE or systemic sclerosis
- Different from undifferentiated CTD (UCTD): nonspecific symptoms that fail to meet criteria for any CTD; 30% go on to develop CTD over 3-5 y (usually SLE)
Clinical & laboratory manifestations (Rheumatology 2018;57:255)
- Raynaud’s phenomenon (qv) typical presenting symptom (75-90%)
- Hand edema (“puffy hands”), sclerodactyly, RA-like arthritis w/o erosions, polyarthralgias
- Pulmonary involvement (85%) with pulmonary hypertension, fibrosis
- Pericarditis most frequent cardiovascular manifestation; GI: dysmotility (70%)
- Membranous & mesangial GN common (25%); low risk for renal HTN crisis or severe GN
- ⊕ ANA (>95%); ⊕ RF (50%); requires ⊕ anti-U1-RNP but not specific (seen in ~50% SLE)