Mondo Description Secondary amyloidosis is a form of amyloidosis, that complicates chronic inflammatory disorders (mainly rheumatoid arthritis) and is characterized by the aggregation and deposition of amyloid fibrils composed of serum amyloid A protein, an acute phase reactant. Although spleen, suprarenal gland, liver and gut are frequent sites of amyloid deposition, the clinical picture is dominated by renal involvement.