Minimal change disease (MCD) is a common cause of nephrotic syndrome and relatively well responds with steroid treatment. However, nearly half of patients with MCD experience recurrence of nephrotic syndrome. Thromboembolic events including renal vein thrombosis may occur in patients with MCD, but portal vein thrombosis rarely occurs. We experienced a case of frequent relapse/steroid dependent MCD with nephrotic syndrome progressed to steroid resistance associated with portal vein thrombosis. This patient showed complete remission of MCD and resolution of portal vein thrombosis after treatment with corticosteroid, cyclosporine, mycophenolate mofetil, and anticoagulant.

Klinefelter' syndrome is a disorder of sexual differentiation in males, characterized by the presence of two or more X-chromosomes, hypogonadism, and lack of secondary sexual characteristics. The association between Klinefelter' syndrome and glomerulonephritis has been reported, while cases of glomerulonephritis associated with Klinefelter' syndrome are rare. We report the Korean case: a 31-year-old man with Klinefelter' syndrome who developed glomerulonephritis. The patient's urine analysis shows microscopic hematuria and the result of kidney biopsy was minimal change disease. The onset and course of his disease might have been influenced by the sex hormone imbalance.