AL amyloidosis

A clonal B-cell disorder characterized by the aggregation and deposition of insoluble amyloid fibrils derived from misfolding of monoclonal immunoglobulin light chains. It usually presents as systemic AL amyloidosis with involvement of one or more parenchymal organ(s) and, less frequently, as localized amyloidosis with usually nodular deposits restricted to a single organ and/or system.