[Amyloidosis and renal failure]

A heterogeneous group of disorders associated with abnormal extracellular deposition of fibrillar proteins is defined amyloidosis. The renal involvement may occur in the absence of a recognized underlying disease or the kidney is affected as a result of systemic amyloidosis. Even if the diagnosis can only be confirmed by demonstrating the presence of amyloid deposits in the tissues, the development of a radiolabelled serum amyloid P component as a diagnostic nuclear tracer and the reduced urinary excretion of glycosaminoglycans as a decrease in the synthesis of functioning glomeruli and trapping by amyloid fibrils allow new diagnostic insight for the future. Patients maintained on haemodialysis or continuous ambulatory peritoneal dialysis for long develop amyloid deposits composed of beta 2 microglobulin that are predominantly osteoarticular, associated with carpal tunnel syndrome, large-joint pain, stiffness and pathological fractures. Systemic amyloidosis and some local forms are progressive and no treatment specifically resolves the amyloid deposits but therapy may reduce amyloid precursor proteins and improve survival.