Amyloidosis Flashcards
What is an amyloid?
Misfolded protein that deposits in extracellular space
For a protein to be considered an amyloid what characteristics it must have?
B pleated sheet configuration
How are amyloids seen in histology?
Congo red stain and apple green birefringence under polarized lights
Most common place where amyloids deposits?
Around blood vessels
What are the types of systemic amyloidosis?
Primary and secondary amyloidosis
In Primary amyloidosis what type of amyloid is deposit
AL amyloid
*** from the light chain of Ig
Mechanism of plasma cell dyscrasia generates amyloidosis
1, Plasma cell overproduction of Ig light chain
- Leak into blood
- Gets misfold
- Deposits in tissue
In secondary amyloidosis what type of amyloid is deposit
AA amyloid
** derivates form SAA
What is SAA?
Acute phase reactant
In which circumustances there is an increase of SAA?
Chronic inflammation (LES, chrons disease, colitis, chronic osteomyelitis)
Malignancy
Familial Mediterranean Fever
What is Familial Mediterranean Fever
Autosomical recessive dysfunction of neutroplis that occurs in person of mediterranean origins
Clinical presentation of Familial Mediterranean Fever
Episodes of fever + Acute serosal inflammation
Type of amyloid found in Familial Mediterranean Fever
AA amyloid
Most common organ where amyloidosis takes place?
Kidney
Classic clinical finding of amyloidosis?
Nephrotic syndrome
restrictive cardiomyopathy or arrhythmia
Tongue enlargement, malabsorption, hepatosplenomegaly
Patient with posible diagnosis of amyloidosis. How do you confirm the diagnosis?
Tissue biopsie
** Accesible targets: Abdominal fat pad and rectum
T/F: Damaged organ of amyloidosis gets back to normal once the treatment is started
False
Amyloid cant be removes– organ must be transplanted in systemic amyloidosis
6 Examples of localized amyloidosis
- Senile cardiac amyloidosis
- Familial amyloid cardiomyopathy
- NIDDM
- Alzheimer disease
- Dyalisis associated amyloidosis
- Medullary carcinoma of thyroid
Type of amyloid found in Senile Cardiac amyloidosis
Non mutated serum transthyretin deposits in heart
*** Elderly, asx
Type of amyloid found in Familial Amyloid cardiomyophathy
Mutated serum transthyretin deposits in heart
** Afroamericans, restrictive cardiomyopathy
Type of amyloid found in NIDDM?
Amylin deposits in islets of pancreas
*** derived from insulin
Type of amyloid found in Alzheimer disease?
AB amyloid deposits in brain
*** Derives from B amyloid precursor protein
Why patients with down syndrome can have early on set of alzheimer?
- Down syndrome( 2 copies of chromosome 21)
- In chromosome 21 there is the gene that produces amyloid precursor protein
- Increase Ab amyloid that deposits in brain
Type of amyloid found in Dyalisis associated mayloidosis
B2 microgloblin deposits in joints
*** it isn’t well filtered in dyalisis, so it accumulates in joints
