Amyloidosis Flashcards
Amyloid
1) Mis-folded protein
2) Deposits in the extracellular space
3) Causing damage of tissues
Amyloidosis
Abnormal aggregation of proteins (or their fragments)
Amyloidosis aggregates into
β-pleated linear sheets —> insoluble fibrils
Amyloidosis cause? and Deposition can be?
Cellular damage and apoptosis
Deposition can be systemic or localized
Amyloid deposits visualized by
Congo red stain
non-polarized light
Red/orange
polarized light
apple-green birefringence
Systemic Amyloidosis
Amyloid deposition in multiple organs
Primary amyloidosis
1) Systemic deposition of AL amyloid
2) Derived from immunoglobulin light chain
3) Associated with plasma cell dyscrasias (multiple myeloma
Secondary amyloidosis
Systemic deposition of AA amyloid Derived from serum amyloid-associated protein (SAA) SAA is an acute phase reactant that is increased in: Chronic inflammatory states: - Rheumatoid arthritis - inflammatory bowel disease Malignancy Familial Mediterranean fever (FMF)
most common organ involved in amyloidosis
Kidney
Classic findings include
Nephrotic Syndrome (kidney: most common organ involved) Restrictive cardiomyopathy or arrythmia Tongue enlargement Malabsorption Hepatosplenomegaly Easy bruising Neuropathy Carpal tunnel syndrome
Diagnosis requires tissue biopsy from?
abdominal fat and rectum
Amyloid can be removed (true or false)
False
Damaged organs must be transplanted (true or false)
True
Localized amyloidosis
Amyloid deposition usually localized to a single organ
Types of localized amyloidosis:
Senile cardiac amyloidosis Familial amyloid cardiomyopathy Non-insulin-dependent diabetes mellitus (type II) Alzheimer disease Dialysis associated amyloidoses Medullary carcinoma of the thyroid Familial amyloid neuropathy
Senile cardiac amyloidosis
Non mutated serum transthyretin
Deposits in the heart
Familial amyloid cardiomyopathy
Mutated serum transthyretin Deposits in the heart Leading to restrictive cardiomyopathy Hereditary 5% of African Americans are carriers of mutant allele
Non-insulin-dependent diabetes mellitus (type II):
Amylin (derived from insulin)
Deposits in the islets of the pancreas
Alzheimer disease
Aβ amyloid (derived from β-amyloid precursor protein)
Deposits in the brain forming amyloid plaques
Dialysis associated amyloidosis
β2-microglobulin
Deposits in joints
Medullary carcinoma of the thyroid
Calcitonin (produced by tumor cells)
Deposits within the tumor
Familial amyloid neuropathy
Mutated transthyretin
