Light-chain glomerulopathy with amyloid-like deposits.

A 40-year-old man with rapidly progressive renal failure was found to have a lobular glomerulonephritis by renal biopsy. Immunofluorescent microscopy showed prominent glomerular deposition of both kappa and lambda light chains but no significant heavy-chain component. Ultrastructurally, electron-dense deposits in the mesangium and capillary basement membranes had a fibrillar appearance indistinguishable from amyloid. This case illustrates a "light-chain glomerulopathy" distinct from previously reported glomerulopathies associated with the deposition of light chains of a single subclass.