A case of thin basement membrane syndrome associated with idiopathic membranous nephropathy.

A 59-year-old woman has had persistent microscopic hematuria for 10 years. A few days after the onset of upper respiratory tract infection, edema and severe proteinuria appeared. In renal biopsy, an electron micrograph revealed electron dense deposits in the subepithelial regions with diffuse thinning of the glomerular basement membrane. These glomerular findings were compatible with thin basement membrane syndrome associated with membranous nephropathy. On the basis of our review of the literature, the association of these two diseases seems to be very rare.