Mctd

Mixed connective tissue disease (MCTD) is an overlap autoimmune syndrome characterized by features of systemic lupus erythematosus, systemic sclerosis, polymyositis, and rheumatoid arthritis occurring in the presence of high-titer anti-U1 ribonucleoprotein (anti-U1 RNP) antibodies. The anti-U1 RNP antibodies target the U1 small nuclear ribonucleoprotein complex involved in mRNA splicing, and their pathogenic role involves immune complex deposition, complement activation, and T-cell-mediated tissue injury across multiple organ systems. The hallmark clinical feature is Raynaud phenomenon with puffy, swollen fingers (sausage digits) that may evolve over years into sclerodactyly. Organ involvement includes pulmonary arterial hypertension (the leading cause of death), interstitial lung disease, esophageal dysmotility, inflammatory myopathy with elevated CK, polyarthritis, and serositis. The nurse monitors for Raynaud phenomenon and digital ulceration, assesses respiratory status and monitors for pulmonary hypertension symptoms (progressive dyspnea, exertional intolerance), monitors muscle strength and CK levels, assesses swallowing function, administers immunosuppressive therapy as prescribed, educates about cold avoidance, and coordinates multidisciplinary follow-up with rheumatology, pulmonology, and cardiology.