Amyloidosis

Definition

• A variety of diseases all characterized by tissue deposition of proteins

Types

AL amyloidosis

• Immunoglobulin light chain deposition disease related to plasma cell dyscrasias
• Can be primary or secondary to multiple myeloma (or, rarely, Waldentröm macroglobulinemia)

AA amyloidosis

• Often secondary to RA, spondyloarthropathy, IBD, chronic infections, heredofamilial periodic fever syndromes, or neoplasms
• Most commonly involvs the kidney, though heart and other oragns may also be involved

Dialysis-related

• Deposition of beta-2 microglobin fibrils that accumulate in end-stage renal disease while on dialysis
• Predominantly affects muskuloskeletal structurs
  • Scapulohumeral joint
  • Rotator cuff most
  • Carpal tunnel

Heritable myoidoses

• Many mutations can lead to this

Age-related senile systemic amyloidosis (SSA)

• Deposition of wild-type transthyretin
• Often involves heart, causing age-related cardiomegaly and heart failure
  • Common on autopsy, often clinically insignificant
• Renal involvement is rare, but can cause carpal tunnel syndrome

Organ-specific amyloidosis

• Alzheimer disease
• Macular, nodular, and lichen cutaneous amyloidosis
• Bladder amyloidosis causing dysuria and severe hemorrhage
• Many others