ABSTRACT
MCTD (Mixed Connective Tissue Disease) is a rare disease characterized by clinical characteristics of patients with overlapping features of SLE (systemic lupus erythematosus), SS (systemic sclerosis), and PM (polymyositis), and serologically characterized by high titers of Anti U1 RNP Ab. At early stage, finger swelling or Raynaud's phenomenon with high titers of Anti U1 RNP Ab are only apparent. Proteinuria and membranous nephropathy are characteristic renal manifestation of MCTD. Recently we had the opportunity to observe patient with Raynaud's phenomenon, finger swelling, high titers of Anti U1 RNP Ab, and asymptomatic proteinuria who underwent a renal biopsy. The patient was diagnosed as early MCTD and renal histology revealed membranous nephropathy. Our purpose is to report this patient and to review the literature.