A Case of Bad Prognosis for Membranous Nephropathy in a Patient with Mixed Connective Tissue Disease

ABSTRACT

Incidence of renal involvement in mixed connective tissue disease (MCTD) is low. In the presence of glomerulonephritis, membranous nephropathy (MN) in MCTD is common. A 47-year-old woman presented with hypothyroidism. She developed Raynaud's phenomenon, arthralgia, and incomplete lupus erythematosus, diagnosed with MCTD. One year after then, the patient developed persistent proteinuria (1+) without hematuria. Following diagnosis with MCTD, her renal function began to deteriorate. The renal biopsy showed late stage MN. For the treatment of MN with mild proteinuria and MCTD, we prescribed an angiotensin II receptor blocker and 7.5 mg of methotrexate per week and 300 mg of hydroxychloroquine daily. The patient had a reduced estimated glomerular filtration rate of 55% for the subsequent eight years. The MN in MCTD is known to show good renal prognosis. Here, we report on a rare case of MN in MCTD in Korea with a bad prognosis.