Amyloidosis

1. Amyloidosis
Dr. Amitabha Basu

2. What is amyloid (amylin : starch-like)?
►Def : Homogeneous, Pink, extra cellular ,
pathologic material.

3. Nature of Amyloid
A. Physical Nature : non branching protein
fibrils 7.5 -10 nm in diameter. Beta pleated
sheet.
B. Chemical nature :
95% Protein Fibril

4. Beta-Pleated Sheet

5. Chemical nature
►Amyloid = 95% Protein Fibril + 5%
Glycoprotein P component - pentagonal
molecule
►Many different chemical types of amyloid
►Common types
Amyloid associate ( AA)
Amyloid light chain (AL)

6. Pathogenesis
►Precursor of AA = SAA ( Serum Amyloid
Associate protein from liver): chronic
inflammation.
►Precursor of AL = Immunoglobulin from
plasma cells = ? Multiple Myeloma .

7. Amyloidosis
►Def : Disease characterized by deposition of
amyloid in the tissue.

8. Classifications of Amyloidosis
A. Systemic amyloidosis
1. Primary amyloidosis
2. Secondary amyloidosis
B. Localized amyloidosis
1. Senile cerebral
2. Senile cardiac
3. Type 2 diabetes.

9. Primary systemic amyloidosis
Disease name Type of
amyloid in the
tissue
Precursor
Multiple
Myeloma
AL Ig lambda
(or kappa
chains)

10. Secondary systemic amyloidosis
Disease name Type of amyloid
in the tissue
Chronic inflammatory
disease.
AA
Hemodialysis associate
amyloidosis in chronic
renal failure.
A-beta 2 micro
globulin.
(Aβ2- micro
globulin)
Rheumatoid arthritis AA

11. Localized amyloidosis : mainly
due to aging
Disease name Type of amyloid
in the tissue
Senile cerebral
amyloidosis:
Alzheimer's
disease
Amyloid beta
protein
(Aß)
Type 2
diabetes
Islet amyloid
polypeptide
( AIAPP) in islet
of Langerhans

12. Disease and amyloid
Multiple Myeloma ( Primary) AL
Rheumatoid arthritis/ TB
( secondary, reactive)
AA
Senile systemic amyloidosis,
familial polyneuropathies
TTR
Acute Familial
Mediterranean Fever
AA
Hemodialysis associated Aβ2 micro globulin
Alzheimer's disease Amyloid beta
Medullary CA thyroid calcitonin

13. Special stain and amyloid
►Lugals iodine: Used only on gross specimen
►PAS: Stain P component ( in Biopsy
specimen)
►Congored : Most important (in Biopsy
specimen)

14. Special stain and amyloid
►Lugals iodine : Brown in gross specimen of
heart.

15. Special stain and amyloid
Congo red ( normal
light)
Brick red
Congo red ( polarized
light)
Apple green
birefringence

16. Morphology
►Gross of any organ with amyloidosis :
Waxy in nature.

17. Amyloidosis of kidney ; amyloid deposit
in the mesengeum of the glomerular
tuft

18. Amyloid in heart : name the stain
and viewing light

19. Clinical manifestation
Kidney Nephrotic syndrome,
protenuria, renal failure
Tongue , GIT Macroglossia,
malabsorpton
Heart Cardiomegaly, heart
failure
Bone marrow
involvement in
Multiple Myeloma.
Fracture/ Multiple
myeloma

20. Laboratory findings
1. Biopsy from gingiva and rectum and
special stain.
2. Diagnosis of Multiple Myeloma associated
amyloid (AL).
1. Presence of M-band in electrophoresis.
2. Bens-Jones protein in the urine.
3. Increased light chain and monoclonal Ig.

21. Presence of
M-band in
electrophoresis

22. Disease and Amyloid
►Primary amyloidosis: AL,
►Secondary amyloidosis : AA,
►Hereditary (familial) amyloidosis: ATTR

23. Disease and amyloid
Multiple Myeloma ( Primary) AL
Rheumatoid arthritis/ TB
( secondary, reactive)
AA
Senile systemic amyloidosis,
familial polyneuropathies
TTR
Acute Familial
Mediterranean Fever
AA
Hemodialysis associated Aβ2 micro globulin
Alzheimer's disease Amyloid beta
Medullary CA thyroid calcitonin

24. Thank you