Key Information
Amyloidosis is a rare disease caused by extracellular deposition of proteins in an insoluble beta-pleated physical conformation. Multiple causative proteins have been identified in amyloidosis, all leading to a similar alteration in structural change, thus leading to extracellular deposition of fibrils.
The kidney is a common site of amyloid deposition in AL, AA, and the hereditary amyloidosis. Amyloid kidney can be difficult to recognize because of its subtle presentation and insidious progression. In fact, most cases of amyloidosis are diagnosed after recognition of multiorgan dysfunction, including heart failure, renal insufficiency associated with proteinuria, autonomic dysregulation, and neuropathy. Accordingly, the incidence of amyloid-related kidney disorders is difficult to firmly estimate; however, it appears to be rising over recent years.
Without treatment, amyloidosis is ultimately fatal because of progressive multisystem organ failure. The kidney is one of the most common sites of involvement in AL amyloidosis, with some series describing clinically evident renal disease in 48%-82% of patients. Recently, newer technology (eg, mass spectrometry) has allowed for earlier diagnosis and recognition of new pathogenic fibrils. Subsequently, this allows for improved risk stratification and treatment options.