Amyloidosis: Pathogenesis and Clinical Features
Start with the big picture
Amyloid fibrils arise when the production and clearance of normally soluble precursor proteins become imbalanced. Their β-pleated sheet structure is associated with characteristic staining, including Congo red positivity with apple-green birefringence. The major fibril proteins include AL, AA, Aβ, ATTR and β₂-microglobulin, each linked to different clinical settings. Amyloidosis may be systemic or localized, with causes ranging from plasma-cell dyscrasia and chronic inflammation to inherited transthyretin mutations and long-term dialysis. The kidneys are commonly affected; cardiac, gastrointestinal, nerve and skin findings also occur. Clinical features reflect the sites of deposition and may include nephrotic syndrome, restrictive cardiomyopathy, neuropathy and characteristic skin changes.
What you'll learn
- Explain how an imbalance in precursor-protein production and clearance leads to amyloid deposition.
- Identify the structural and staining features associated with amyloid fibrils.
- Distinguish major amyloid types by precursor protein and associated clinical setting.
- Relate organ deposition to characteristic renal, cardiac, gastrointestinal, nerve and skin manifestations.
Continue your study
Work through the complete notes and reinforce the topic with the study tools available in the full lesson.
