Amyloidosis
Dr. Amitabha Basu
What is amyloid (amylin : starch-like)?
► Def
: Homogeneous, Pink, extra cellular ,
pathologic material.
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
Beta-Pleated Sheet
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)
Pathogenesis
► Precursor
of AA = SAA ( Serum Amyloid
Associate protein from liver): chronic
inflammation.
► Precursor
of AL = Immunoglobulin from
plasma cells = ? Multiple Myeloma .
Amyloidosis
► Def
: Disease characterized by deposition of
amyloid in the tissue.
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.
Primary systemic amyloidosis
Disease name
Multiple
Myeloma
Type of
Precursor
amyloid in the
tissue
AL
Ig lambda
(or kappa
chains)
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
Localized amyloidosis : mainly
due to aging
Disease name
Type of amyloid
in the tissue
Senile cerebral Amyloid beta
amyloidosis:
protein
Alzheimer's
(Aß)
disease
Type 2
diabetes
Islet amyloid
polypeptide
( AIAPP) in islet
of Langerhans
Disease and amyloid
Multiple Myeloma ( Primary) AL
Rheumatoid arthritis/ TB
AA
( secondary, reactive)
Senile systemic amyloidosis, TTR
familial polyneuropathies
Acute Familial
Mediterranean Fever
Hemodialysis associated
AA
Alzheimer's disease
Amyloid beta
Medullary CA thyroid
calcitonin
Aβ2 micro globulin
Special stain and amyloid
► Lugals
iodine: Used only on gross specimen
► PAS: Stain P component ( in Biopsy
specimen)
► Congored : Most important (in Biopsy
specimen)
Special stain and amyloid
► Lugals
heart.
iodine : Brown in gross specimen of
Special stain and amyloid
Congo red ( normal
light)
Congo red ( polarized
light)
Brick red
Apple green
birefringence
Morphology
► Gross
of any organ with amyloidosis :
Waxy in nature.
Amyloidosis of kidney ; amyloid deposit
in the mesengeum of the glomerular
tuft
Amyloid in heart : name the stain
and viewing light
Clinical manifestation
Kidney
Nephrotic syndrome,
protenuria, renal failure
Tongue , GIT
Macroglossia,
malabsorpton
Heart
Cardiomegaly, heart
failure
Bone marrow
Fracture/ Multiple
involvement in
myeloma
Multiple Myeloma.
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.
Presence of
M-band in
electrophoresis
Disease and Amyloid
► Primary
amyloidosis: AL,
► Secondary amyloidosis : AA,
► Hereditary (familial) amyloidosis: ATTR
Disease and amyloid
Multiple Myeloma ( Primary) AL
Rheumatoid arthritis/ TB
AA
( secondary, reactive)
Senile systemic amyloidosis, TTR
familial polyneuropathies
Acute Familial
Mediterranean Fever
Hemodialysis associated
AA
Alzheimer's disease
Amyloid beta
Medullary CA thyroid
calcitonin
Aβ2 micro globulin
Thank you