Amyloidosis: Structure, Appearance, and Diagnosis PDF

Amyloidosis Structure, appearance and diagnosis Dr. Erika Bracamonte Division Chief, Anatomic Pathology Department of Pathology [email protected]  Amyloidosis Definition – Amyloidosis is a condition associated with a number o...

Amyloidosis Structure, appearance and diagnosis Dr. Erika Bracamonte Division Chief, Anatomic Pathology Department of Pathology [email protected]  Amyloidosis Definition – Amyloidosis is a condition associated with a number of inherited and inflammatory disorders, in which extracellular deposits of fibrillary proteins are responsible for tissue damage and functional compromise Not a single entity; >20 different proteins can make amyloid – All result in formation of protein with specific characteristics and classic appearance in tissue  Physical and Chemical Properties Amyloid proteins are insoluble, aggregate together and deposit as fibrils – Non-branching fibrils, 7.5 -10nm in diameter Characteristic β-pleated sheet configuration – Present in ALL types of amyloid How diagnosis is made Congo Red histochemical stain – Used to detect amyloid in tissue sections – Amyloid stains red/salmon color – Apple green color (birefringence) seen under polarized light  Congo Red stain: Red/salmon = positive for amyloid amyloid β-pleated sheet seen btw tubulesof kidney Congo Red: Apple Green birefringence Under polarized light Robbins and Cotran Pathologic Basis of Disease  Composition of Amyloid 95%: Fibril proteins – Important types: if AL (amyloid light chains) – Plasma cell disorders AA (amyloid associated) – Systemic inflammatory diseases ex RA colitis Aβ (β-amyloid) – Alzheimer’s disease 5%: Amyloid P component, other glycoproteins  Diagnosis of Amyloidosis CANNOTdiagnose You Requires tissue: without tissue – Abdominal fat pad aspirate or biopsy Less invasive vs deep organ biopsy Poor sensitivity more but – Biopsy from affected organs: invasive H&E (routine stain): Accumulation of amorphous, pale eosinophilic material within tissue – Smudgy, “Toothpaste-like” appearance Positive Congo Red stain with apple green birefringence Some forms of amyloid can be detected by specialized immunohistochemical stains  Diagnosis of Amyloidosis tell us Requires tissue: will not f – Electron Microscopy: the athfford Identification of amyloid fibrils at ultrastructural level – Mass spectrometry: 8 Ie team Fid Amyloid protein micro-dissected from tissue Allows for more precise identification of type of amyloid Send out test (performed at Mayo Clinic)  run mass Spect Widney biopsy Congo red stain shows birefringence http://www.amyloidosissupport.org/AmyloidAware_Booklet.pdf Normal Kidney (Glomerulus) N  l l Amyloidosis in the Kidney (Glomerulus) H&E Congo Red Stain l l clogged  I 99 w amyloid Amyloidosis in the Liver Congo red I firefringence Robbins and Cotran Pathologic Basis of Disease Cardiac Amyloidosis catyloid cause fatal 9 11 amyloid https://app.expertpath.com Cardiac Amyloidosis I birefringence https://app.expertpath.com  Amyloid Fibrils Electron Microscopy are On EM fibrils haphazardly arranged do not branch 7.5 – 10 nm in thickness  What is the key histologic stain used to confirm a diagnosis of amyloid in tissue? A. Hematoxylin and Eosin (H&E) 0 B. C. Congo Red Trichrome D. Silver stain  What is the key histologic stain used to confirm a diagnosis of amyloid in tissue? A. Hematoxylin and Eosin (H&E) B. Congo Red C. Trichrome D. Silver stain  Electron Microscopy can distinguish different types of amyloid protein TRUE FALSE  Electron Microscopy can be performed to distinguish different types of amyloid protein TRUE FALSE – All amyloid fibrils look the same (size, shape) by electron microscopy – Typing of amyloid is performed by mass spectrometry Must use mass spectrometry  Amyloidosis Specific Types Dr. Erika Bracamonte Division Chief, Anatomic Pathology Department of Pathology [email protected]  Systemic Amyloid Primary Amyloidosis (AL) Type Plasma cell disorder neoplasti plasma cell which churns out one Most common form of amyloidosis type of immunoglobulin light chain either Kappa or lambda Etiology: Plasma Cell disorder forms the fibril Amyloid fibril protein: AL (immunoglobulin light chain) – Secreted by abnormal, monoclonal proliferation of plasma cells Monoclonal light chains can be found in patient’s urine – “Bence-Jones proteinuria” Urine can show chain level highBence type of of one light Jonesproteinuria y a Jte aÉt ead http://www.haematologica.org/content/haematol/99/2/209/F1.large.jpg?width=800&height=600&carousel=1 Primary Amyloidosis (AL) looking glomerulus see whether one type of light chain i K or ii A is more represented Lambda Kappa Reactive Systemic Amyloidosis (AA) Type Etiology: Systemic inflammatory disease – Autoimmune diseases: Rheumatoid arthritis, ankylosing spondylitis, inflammatory bowel disease – Infection: Heroin abusers who inject into skin with resulting chronic skin infections (“skin popping”) Osteomyelitis – Malignancy associated inflammation Renal cell carcinoma, Hodgkin lymphoma Amyloid fibril protein: AA (amyloid associated protein) – Derived from serum amyloid A protein synthesized in the liver in response to systemic inflammation http://www.amyloidplanet.com/ AA Amyloidosis - Glomerulus Amyloid A Immunohistochemistry  Systemic Amyloid Hemodialysis-Associated Amyloidosis Etiology: Long term dialysis for renal failure Amyloid fibril protein: β-2 microglobulin Less common now than in the past bonecysts related to amyloid – New dialysis filters remove β-2 microglobulin from circulation before it can build up Tendency to go to bone, tendons and skin http://intranet.tdmu.edu.ua/data/kafedra/internal/vnutrmed2/classes_stud/en/med/lik/ptn/Interna l%20medicine/5%20course/21.%20Acute%20and%20chronic%20renal%20failure.files/image016.jpg  Systemic Amyloid Leukocyte Cell Derived Chemotaxin -2 (LECT2 Amyloid) Etiology: Unknown – Recently described entity Amyloid fibril protein: LECT2 protein – Secreted by the liver – Signaling agent to regulate functions of other cells Deposits primarily in the kidney (renal failure), may also deposit in liver, lung, spleen, adrenal gland 80-90% of pts with LECT-2 amyloid are Hispanic (Mexican decent) – High incidence in Southwest US Lect2 Amyloidosis Congo Red  what type Lect2 Amyloidosis Congo Red LECT2 Immunohistochemistry  Hereditary Amyloid: Familial Mediterranean Fever Autosomal recessive disease Inflammatory syndrome: – Due to excess production of IL-1 Etiology: – Mutation in gene for protein that encodes pyrin (involved in regulation of inflammation) Icansigna 1 downstream 12 Amyloid fibril protein: AA (amyloid associated) IA – Similar to systemic reactive amyloidosis, but due to Imetype genetic mutation ofprotein– Associated with recurrent bouts of inflammation as the systeinfiammation  Hereditary Amyloid: Familial Amylodiotic Neuropathies Group of autosomal dominant diseases Accumulation of amyloid within peripheral and autonomic nerves Etiology: Mutation in gene encoding for Transthyretin (TTR) protein – Transport protein secreted by liver – Amyloid fibril protein: mutated TTR F y https://jamanetwork.com/data/Journals/NEUR/935143/nlo150017f1.png  Hereditary Amyloid Systemic Senile Amyloidosis “Amyloidosis of aging” – Elderly patients, with genetic susceptibility – Etiology: Precise cause unknown – Amyloid fibril protein: Normal (unmutated) TTR – Dominant involvement of heart, can also involve other organs Amyloid Cardiac muscle  Localized Amyloid “Amyloidoma” Discrete nodular masses of amyloid form in one specific organ – Lung, larynx, skin, urinary bladder, tongue, eye Etiology: Multifactorial Amyloid fibril protein: Varies, depending on etiology – Rarely, localized amyloid may be composed of AL amyloid and associated with plasma cell disorder  Localized Amyloid in Larynx https://file.scirp.org/pdf/_2017010915011506.pdf https://app.expertpath.com Amyloidoma of Mediastinum https://radiopaedia.org/images/26817  Localized Amyloid: Alzheimer’s Disease Cerebral amyloidosis Etiology: – Amyloid forms plaques in brain parenchyma and injures neurons Amyloid fibril protein: Aβ (β- amyloid) – Derived from amyloid precursor protein (APP) Transmembrane protein concentrated in neuronal synapses  Alzheimer’s Disease β-amyloid Brain Atrophy Robbins and Cotran Pathologic Basis of Disease  Localized Amyloid: Medullary Carcinoma of Thyroid Etiology: Malignant neoplasm of thyroid composed of calcitonin-secreting C-cells Amyloid fibril protein: A Cal (from calcitonin) Identification of amyloid in a thyroid tumor helpful to make the diagnosis of medullary carcinoma Robbins and Cotran Pathologic Basis of Disease  Localized Amyloid: Diabetes Mellitus Amyloid infiltrates into pancreatic Islets of Langerhans Etiology: Type 2 Diabetes Mellitus Amyloid fibril protein: AIAPP (Islet amyloid polypeptide) Islet of Langerhans with Amyloid Congo Red stain https://library.med.utah.edu/WebPath/jpeg4/ENDO033.jpg  Localized Amyloid: Isolated Atrial Amyloidosis Amyloid deposits in atria of Positive Congo Red with apple heart green birefringence – Restricts atrial motion – Causes atrial dilation, arrhythmias Etiology: Localized overproduction of atrial natriuretic factor (ANF) Amyloid fibril protein: alpha-ANF https://jamanetwork.com/data/Journals/INTEMED/5554/ira60009f2.png  The most common form of amyloidosis is: O A. Primary AL amyloid (due to a plasma cell disorder) B. Aβ amyloid (Alzheimer’s disease) C. Reactive systemic AA amyloid (due to a systemic inflammatory disease) D. Β2-macroglobulin amyloid (associated with hemodialysis)  The most common form of amyloidosis is: A. Primary AL amyloid (due to a plasma cell disorder) B. Aβ amyloid (Alzheimer’s disease) C. Reactive systemic AA amyloid (due to a systemic inflammatory disease) D. Β2-macroglobulin amyloid (associated with hemodialysis) Which of these types of amyloid is due to hereditary (inherited) disease? A. A-Cal amyloid in medullary thyroid cancer 0 B. ATTR amyloid in peripheral and autonomic nerves C. Alpha-ANF in atria of the heart D. AA amyloid in rheumatoid arthritis Which of these types of amyloid is due to hereditary (inherited) disease? A. A-Cal amyloid in medullary thyroid cancer B. ATTR amyloid in peripheral and autonomic nerves C. Alpha-ANF in atria of the heart D. AA amyloid in rheumatoid arthritis  Amyloidosis Clinical Manifestations & Treatment Dr. Erika Bracamonte Division Chief, Anatomic Pathology Department of Pathology [email protected]  Clinical Manifestations of Amyloid General/constitutional – Weakness, weight loss, light headedness, syncope (fainting) Skin – Tan/pink papules and plaques, hemorrhage – Characteristic periorbital involvement https://ars.els-cdn.com/content/image/1-s2.0-S1578219013000619-gr10.jpg https://www.regionalderm.com/Regional_Derm/RD_Large/Systemic_amyloidosis_Goltz9_rd.jpg Clinical Manifestations of Amyloid Kidney – Proteinuria (protein in urine): Due to amyloid infiltration into glomerulus – Renal failure: Progressive amyloid deposition leads to fibrosis and nephron loss (poor prognosis) End stage: Requires dialysis and/or transplantation Normal glomerulus Glomerulus with amyloid Congo Red Stain Clinical Manifestations of Amyloid Heart – Congestive heart failure/restrictive cardiomyopathy Dysfunction and compression atrophy of cardiac muscle Lack of contraction – “stiffening” of cardiac muscle, poor ejection of blood – Arrhythmias/conduction abnormalities Amyloid deposition interferes with normal conduction pathways Can lead to sudden cardiac death  Clinical Manifestations of Amyloid Gastrointestinal tract Massive macroglossia due to AL amyloid – Macroglossia Cardinal sign of amyloid due to infiltration of tongue – Malabsorption, diarrhea Involvement of stomach, intestines – Liver involvement Often does not interfere with hepatic function, even when present  Clinical Manifestations of Amyloid Blood vessel involvement – Leads to hemorrhage – Increased fragility of affected vessels – Can be sudden and cause massive blood loss – May be spontaneous or due to injury/trauma Section of brain with amyloid in vessels  Amyloidosis Treatment Variable, depends on type of amyloid, involved organs and underlying etiology AL Type – Chemotherapy to target malignant plasma cell clone – Bone marrow transplant AA Type – Treat underlying etiology/inflammatory condition Alzheimer’s Disease – New agents in clinical trials: Immunotherapy – monoclonal antibodies to target β-amyloid Β-secretase and γ-secretase inhibitors – block cleavage of amyloid precursor protein Familial Mediterranean fever – Colchicine – reduces mobility of PMN’s to decrease their response to pro-inflammatory cytokines – Anti-IL-1 therapy (investigational)  Eprodisate – structure similar to heparin sulfate – Competitively binds to serum amyloid A protein and inhibits fibril formation/amyloid deposition – Most recent phase 3 trial - disappointing results, did not show efficacy for FDA approval   Amyloidosis Summary Heterogeneous disorder, variable etiologies Can be localized or systemic; some have a genetic/hereditary component Tissue is REQUIRED for diagnosis – Congo red positive with apple green birefringence – Classification of type of amyloid based on clinical presentation + tissue biopsy (w/mass spec) + other laboratory findings Treatment – depends on amyloid type, etiology Prognosis generally poor – Some new therapies in development A 73-year-old male presents with fatigue, weight loss, and shortness of breath. Urinalysis shows increased lambda light chains, although renal function is normal. EKG shows arrhythmia and echocardiogram demonstrates restrictive cardiomyopathy. What is the best test to clinch the diagnosis? A. Pulmonary function tests B. Kidney biopsy C. Abdominal fat pad aspirate D. Endomyocardial heart biopsy E. Chest X-ray A 73-year-old male presents with fatigue, weight loss, and shortness of breath. Urinalysis shows increased lambda light chains, although renal function is normal. EKG shows arrhythmia and echocardiogram demonstrates restrictive cardiomyopathy. What is the best test to clinch the diagnosis? A. Pulmonary function tests B. Kidney biopsy C. Abdominal fat pad aspirate D. Endomyocardial heart biopsy E. Chest X-ray