Pathoma- Amyloid Flashcards
What do thyroid tumor cells in an amyloid background indicate?
medullary carcinoma of the thyroid
What is amylin?
an amyloid that is a byproduct of insulin that can deposit in the islets of the pancreas
What is senile cardiac amyloidosis?
non-mutated serum transthyretin deposits in the heart present in 25% of individuals >80yo usually asymptomatic
Name the localized amyloidoses.
- familial amyloid cardiomyopathy 2. senile cardiac amyloidosis 3. DM associated 4. Alzheimers 5. dialysis-associated amyloidosis 6. medullary carcinoma of the thyroid
What is medullary carcinoma of the thyroid?
a thyroid tumor derived from C cells, leading to overproduction of calcitonin and then amyloid deposition in the thyroid
Dx? beta-2-microglobulin deposits in joints
dialysis-associated amyloidosis
How does amyloid look under the microscope?
congo red staining with apple green birefringence
What is dialysis-associated amyloidosis?
beta-2-microglobulin deposits in joints dialysis pts
What is the usual configuration of amyloid-damaged tissue?
Beta-pleated sheets
How can amyloidosis occur in Alzheimers disease?
beta-amyloid precursor protein on chromosome 21 deposits into the brain as ABeta forms amyloid plaques
How can amyloidosis occur in DM?
type 2 DM: too much insulin = insulin byproduct produced (amylin) amylin deposits into islets of the pancreas
How is amyloidosis definitively diagnosed?
a tissue biopsy (usu a fat pad- abdominal or rectal)
What are the features of Familial Mediterranean Fever?
dysfunction of the neutrophils causing activation w/o infection auto recessive inheritance in persons of Mediterranean origin fever; serosal surfaces inflamed; tongue enlargement, hepatosplenomegaly, malabsorption
Name the localized amyloidoses.
- familial amyloid cardiomyopathy 2. senile cardiac amyloidosis 3. DM associated 4. Alzheimers 5. dialysis-associated amyloidosis
What is restrictive cardiomyopathy?
stiffened heart can’t dilate as well or pump properly, leading to HF
How can amyloidosis occur in Alzheimers disease?
beta-amyloid precursor protein on chromosome 21 forms ABeta amyloid forms amyloid plaques in the brain
What is the usual configuration of amyloid-damaged tissue?
Beta-pleated sheets
What is 2a amyloidosis?
systemic deposition of AA amyloid derived from SAA
Where does amyloid most commonly deposit? What does this cause?
the kidney; nephrotic syndrome
What kind of amyloidosis category does senile cardiac amyloidosis fall into?
localized amyloidosis
What is familial amyloid cardiomyopathy?
mutated serum transthyretin deposits in the heart leads to restrictive cardiomyopathy 5% of African Americans are carriers
What is nephrotic syndrome?
a large loss of protein (>3g in 24 hours) in the urine
How are the affected organs treated in amyloidosis?
no tx- they have to be transplanted
Where does amyloid tend to deposit?
around BVs
What is the 2nd most common protein in the blood?
serum transthyretin
What is SAA?
an acute phase reactant increased in inflammation, malignancy, and Familial Mediterranean fever
What is AA amyloid?
an amyloid derived from SAA
Why does dialysis-assoc amyloidosis occur?
Dialysis pts have increased amounts if Beta-2-microglobulin in the blood bc it isn’t filtered out properly- it then accumulates in joints
What are the features of Familial Mediterranean Fever?
dysfunction of the neutrophils causing activation w/o infection auto recessive inheritance in persons of Mediterranean origin fever; serosal surfaces affected