Overview of Mixed Connective Tissue Disease in Adults

Introduction: Mixed connective tissue disease (MCTD) is described as a connective tissue disorder characterized by the presence of high titers of a distinctive autoantibody, now called anti-U1 ribonucleoprotein (anti-RNP). It is assumed to be an overlap syndrome that includes clinical features of major diffuse connective tissue diseases. The overlap feature often take several years to appear clear enough to be establish the confident diagnosis of MCTD. Nowadays, there is a consensus to consider MCTD as a “distinct clinical entity”. Aim of the Work: The definition, criteria, clinical features, prognosis, and general principles of management will be presented in this review. In-depth details of management will not be presented. Methodology: This article is a comprehensive review of medical literature regarding mixed connective tissue disease. Conclusion: In most cases, MTCD cannot be differentiated from other classical DCTDs in the early stages as the simultaneous presence of overlap features seen in SLE, SSc, and polymyositis (PM) is rarely obvious. The overlapping features appear more evident sequentially over several years. Early symptoms are usually puffy fingers, easy fatigability, poorly defined myalgias, arthralgias, lowgrade fever, and Raynaud phenomenon. Mixed connective tissue disease has a relatively good prognosis and excellent response to glucocorticoids due to a low prevalence of serious renal disease and life-threatening neurologic problems. MCTD-associated mortality are substantial in various report, ranging from 16 to 28 percent at 10 to 12 years follow-up. The highest mortality rate is seen in patients with vascular involvement. The primary causes of death include progressive pulmonary hypertension (PAH) and its heart complications. The management of MCTD is generally based upon the known effectiveness of specific therapies for similar diseases.