The Association of Upper Extremity Deep Vein Thrombosis and Homozygosity for the MTHFR 1298A-C Mutation in a Young Women with Membranoproliferative Glomerulonephritis

Nephrotic syndrome increases the tendency to thromboembolic complications in both adults and children. Changes in the plasma concentrations of many proteins concerned with regulation of clotting and fibrinolytic systems, hyperviscosity, dehydration, corticosteroid and diuretic therapy may also contribute to thromboembolism. In addition, some of the genetic disorders also increase tendency to thromboembolic events. One of these disorders is methylene tetrahydrofolate reductase (MTHFR) A1298C mutation, which may cause hyperhomocysteinemia and thrombotic events when the folate level is low. A 26-year-old female was admitted to hospital with upper extremity deep vein thrombosis and nephrotic range proteinuria. On her renal biopsy, membranoproliferative glomerulonephritis (MPGN) was found. The other causes of thrombosis were excluded and homozygosity for the MTHFR A1298C mutation was determined. The levels of homocysteine and folic acid were normal. We report a first case of MPGN together with homozygosity for MTHFR 1298C mutation in adult nephrotic syndrome, complicated with unusual upper extremity venous thrombosis.