Rheumatoid arthritis and amyloidosis?,”Rheumatoid arthritis predisposes to amyloidosis. Renal involvement is characterized by nephrotic syndrome. The classic pathologic finding is amyloid deposits that stain with Congo red and demonstrate apple-green birefringence under polarized light. Multiple myeloma is the most common cause of AL amyloidosis
and rheumatoid arthritis is the most common cause of AA amyloidosis.”