AMYLOIDOSIS Flashcards
What are the antiparallel β-pleated sheet configuration on X-ray diffraction called?
AMYLOID FIBRILS
What 2 stains will amyloid fibrils bind?
- CONGO RED
- THIOFAVIN T
What are the 2 types of amyloidosis?
- AA AMYLOIDOSIS
- AL AMYLOIDOSIS
What is the most common type of Amyloidosis?
AL AMYLOIDOSIS
What type of amyloidosis where the deposited fibrils are derived from the variable portion of immunoglobulin light chains produced by a clonal population of plasma cells or plasmacytic B cells?
AL AMYLOIDOSIS
What type of amyloidosis results from the deposition of serum amyloid A (SAA) protein in chronic inflammatory states?
AA AMYLOIDOSIS
In AL amyloid patients with renal disease what type of chains strongly predominate?
λ-LIGHT CHAINS
What is the ratio of λ-light chains to κ-light chains in pxs with renal disease?
12:1
What is the ratio of λ-light chains to κ-light chains in pxs without renal disease?
4:1
What are the most common major organ involved by AL amyloid?
KIDNEYS
What is the age and gender predilection in AL amyloidosis?
• > 50 years
• MALES
What type of amyloidosis occurs in chronic inflammatory diseases?
AA AMYLOIDOSIS
Where is SAA (Serum Amyloid A) produced?
LIVER
What type of lipoprotein does SAA (Serum Amyloid A) associates in the circulation?
HDL
AA Amyloid is most commonly associated with?
RHEUMATOID ARTHRITIS
AA amyloidosis is also seen in these 7 conditions
- INFLAMMATORY ARTHRITIDES
- IBD
- FMF (Familial Mediterranean Fever)
- QUADRIPLEGICS with chronic UTI & decubitus ulcers
- BRONCHIECTASIS
- OSTEOMYELITIS (poorly treated)
- CHRONIC HEROIN ADDICTS (Injects drugs SQ)
AA Amyloid occurs in what population?
older addicts with a long history of substance abuse who have exhausted sites of intravenous access and resorted to “skin popping” or “muscling”
The diagnosis of amyloid is usually established by?
Tissue biopsy of an affected organ
What diagnostic imaging allows the noninvasive diagnosis of amyloidosis as well as a quantification of the extent of organ system involvement and assessment of the response to treatment?
SAP WHOLE BODY SCINTIGRAPHY
What are the LM findings in Amyloidosis?
GLOMERULI:
• deposition of amorphous hyaline material that begins in the mesangium and extends into the peripheral capillary walls
• Affected glomeruli appear hypocellular and have a nodular aspect.
DEPOSITS:
• lightly eosinophilic
• weakly PAS positive
• nonargyrophilic (contrast to the findings in diabetic nodular glomerulosclerosis)
GBM
• amyloid deposits form spicular hairlike projections
Congo Red staining gives what appearance?
- ORANGE STAINING REACTION
- APPLE-GREEN BIREFRINGENCE UNDER POKARIZED LIGHT
What is the IF findings in AL amyloidosis?
strong staining with antisera to the pathogenic light chain, usually λ
What is the IF finding in AA Amyloidosis?
STRONG REACTIVITY TO SAA PROTEIN
What are the characteristics of Amyloid fibrils by EM?
• nonbranching
• 8-12 nm
• randomly distributed
