Made by DATEXIS (Data Science and Text-based Information Systems) at Beuth University of Applied Sciences Berlin
Deep Learning Technology: Sebastian Arnold, Betty van Aken, Paul Grundmann, Felix A. Gers and Alexander Löser. Learning Contextualized Document Representations for Healthcare Answer Retrieval. The Web Conference 2020 (WWW'20)
Funded by The Federal Ministry for Economic Affairs and Energy; Grant: 01MD19013D, Smart-MD Project, Digital Technologies
Prognosis varies with the type of amyloidosis. Prognosis for untreated AL amyloidosis is poor with median survival of one to two years. More specifically, AL amyloidosis can be classified as stage I, II or III based on cardiac biomarkers like troponin and BNP. Survival diminishes with increasing stage, with estimated survival of 26, 11 and 3.5 months at stages I, II and III, respectively.
Outcomes in a person with AA amyloidosis depend on the underlying disease and correlate with the concentration of serum amyloid A protein.
People with ATTR have better prognosis and may survive for over a decade.
Senile systemic amyloidosis was determined to be the primary cause of death for 70% of people over 110 who have been autopsied.
The three most common forms of amyloidosis are AL, AA, and ATTR amyloidoses. The median age at diagnosis is 64.
In the western hemisphere, AL is the most prevalent, comprising 90% of cases. In the United States it's estimated that there are 1,275 to 3,200 new cases of AL amyloidoses a year.
AA amyloidoses is the most common form in developing countries and can complicate longstanding infections with tuberculosis, osteomyleitis, and bronchiectesis. In the west, AA is more likely to occur from autoimmune inflammatory states. The most common causes of AA amyloidosis in the West are rheumatoid arthritis, inflammatory bowel disease, psoriasis, and familial Mediterranean fever.
People undergoing long term hemodialysis (14–15 years) can develop amyloidosis from accumulation of light chains of the HLA 1 complex which is normally filtered out by the kidneys.
Senile amyloidosis resulting from deposition of normal transthyretin, mainly in the heart, is found in 10–36% of people over 80.
AL amyloidosis is a rare disease; only 1200 to 3200 new cases are reported each year in the United States. Two thirds of patients with AL amyloidosis are male and less than 5% of patients are under 40 years of age.
Median survival for patients diagnosed with AL amyloidosis was 13 months in the early 1990s, but had improved to c. 40 months a decade later.
AA amyloidosis is a complication of a number of inflammatory diseases and infections, although only a small portion of patients with these conditions will go on to develop AA amyloidosis. A natural history study of AA amyloidosis patients published in the New England Journal of Medicine reported a number of conditions associated with AA amyloidosis. The most common presentation of AA amyloidosis is renal in nature, including proteinuria, nephrotic syndrome and progressive development of renal insufficiency leading to End Stage Renal Disease (ESRD) and need for renal replacement therapy (e.g. dialysis or renal transplantation).
- Autoimmune diseases
- Rheumatoid arthritis
- Ankylosing spondylitis
- Crohn's disease and ulcerative colitis
- Chronic infections
- Tuberculosis
- Bronchiectasis
- Chronic osteomyelitis
- Autoinflammatory diseases
- Familial Mediterranean fever (FMF)
- Muckle–Wells syndrome (MWS)
- Cancer
- Hodgkin's lymphoma
- Renal cell carcinoma
- Chronic foreign body reaction
- HIV/AIDS
- Silicone-induced granulomatous reaction
AA amyloidosis is a form of amyloidosis, a disease characterized by the abnormal deposition of fibers of insoluble protein in the extracellular space of various tissues and organs. In AA amyloidosis, the deposited protein is serum amyloid A protein (SAA), an acute-phase protein which is normally soluble and whose plasma concentration is highest during inflammation.
Haemodialysis-associated amyloidosis is a form of systemic amyloidosis associated with chronic kidney failure.
The median time to progression to end stage renal disease is 2.7 years. After 5 years, about 37% of patients with LCDD are alive and do not have end stage renal disease.
Long-term haemodialysis results in a gradual accumulation of β microglobulin, a serum protein, in the blood. It accumulates because it is unable to cross the dialysis filter.
Affected individuals usually present after 5 years of dialysis rarely before that. The tendency of haemodialysis-associated amyloidosis is to be articular in general affecting the joints.
Most individuals diagnosed with LECT2 amyloidosis in the United States (88%) are of Mexican descent and reside in Southwest region of the United States (New Mexico, Arizona, far Western Texas). Other groups with higher incidence rates of the disorder include First Nation Peoples in Canada, Punjabis, South Asians, Sudanese, Native Americans, and Egyptians. In Egyptians, for example, LECT2 is second most common cause of renal amyloidosis, accounting for nearly 31% of all cases.
ALECT2 amyloidosis is generally diagnosed in individuals between the ages 40 and 90, with a mean age of 67 years old. The disorder commonly presents with renal disease that in general is advanced or at an end stage. Associated signs and symptoms of their renal disease may include fatigue, dehydration, blood in urine, and/or other evidence for the presence of the nephrotic syndrome or renal failure. Further studies may find that these individuals have histological or other evidence of LECT2 amyloid deposition in the liver, lung, spleen, kidney, and/or adrenal glands but nonetheless they rarely show any symptoms or signs attributable to dysfunction in these organs. Unlike many other forms of systemic amyloidosis, LECT2 deposition has not been reported to be deposited in the myocardium or brain of affected individuals. Thus, LECT2 amyloidosis, while classified as a form of systemic amyloidosis, almost exclusively manifests clinically as renal amyloidosis. No familial link has been found in the disorder although there have been several cases described among siblings.
The disorder typically affects the heart and its prevalence increases in older age groups. Men are affected much more frequently than women. In fact, up to 25% of men over the age of 80 may have evidence of WTTA.
Patients often present with increased thickness of the wall of the main heart chamber, the left ventricle. People affected by WTT amyloidosis are likely to have required a pacemaker before diagnosis and have a high incidence of a partial electrical blockage of the heart, known as left bundle branch block. Low ECG signals such as QRS complexes are widely considered a marker of cardiac amyloidosis.
A much better survival has been reported for patients with WTTA as opposed to cardiac AL amyloidosis .
Based on studies conducted in the United States, the prognosis for individuals with ALECT2 amyloidosis is guarded, particularly because they are elderly and their kidney disease is usually well-advanced at the time of presentation. End-stage renal disease develops in 1 out of 3 patients and has a median renal survival of 62 months. A suggested prognostic tool is to track creatinine levels in ALect2 patients. The attached Figure gives survival plotss for individuals with LECT2 renal amyloidosis and serum creatinine levels less than 2 mg/100 ml versus 2 mg/100 ml or greater than 2 mg/100 ml. The results show that afflicted individuals with lower creatinine levels have a ~four-fold higher survival rate.
Familial renal amyloidosis (or familial visceral amyloidosis, or hereditary amyloid nephropathy) is a form of amyloidosis primarily presenting in the kidney.
It is associated most commonly with congenital mutations in the fibrinogen alpha chain and classified as a dysfibrinogenemia (see Hereditary Fibrinogen Aα-Chain Amyloidosis). and, less commonly, with congenital mutations in apolipoprotein A1 and lysozyme.
It is also known as "Ostertag" type, after B. Ostertag, who characterized it in 1932 and 1950.
The condition is suspected in an elderly person, especially male, presenting with symptoms of heart failure such as shortness of breath or swollen legs, and or disease of the electrical system of the heart with ensuing slow heart rate, dizziness or fainting spells. The diagnosis is confirmed on the basis of a biopsy, which can be treated with a special stain called Congo Red that will be positive in this condition, and immunohistochemistry.
Although not based on a human clinical trial, the only currently accepted disease-modifying therapeutic strategy available for familial amyloid cardiomyopathy is a combined liver and heart transplant. Treatments aimed at symptom relief are available, and include diuretics, pacemakers, and arrhythmia management. Thus, Senile systemic amyloidosis and familial amyloid polyneuropathy are often treatable diseases that are misdiagnosed.
In 2013, the European Medicines Agency approved the drug tafamidis (Vyndaqel) to slow the progression of familial amyloid polyneuropathy, a related disease caused by TTR aggregation that first presents as an autonomic and/or peripheral neuropathy (later progressing to a cardiomyopathy).
Organ-limited amyloidosis is a category of amyloidosis where the distribution can be associated primarily with a single organ. It is contrasted to systemic amyloidosis, and it can be caused by several different types of amyloid.
In almost all of the organ-specific pathologies, there is significant debate as to whether the amyloid plaques are the causal agent of the disease or instead a downstream consequence of a common idiopathic agent. The associated proteins are indicated in parentheses.
Proteinuria may be a feature of the following conditions:
- Nephrotic syndromes (i.e. intrinsic renal failure)
- Pre-eclampsia
- Eclampsia
- Toxic lesions of kidneys
- Amyloidosis
- Collagen vascular diseases (e.g. systemic lupus erythematosus)
- Dehydration
- Glomerular diseases, such as membranous glomerulonephritis, focal segmental glomerulonephritis, minimal change disease (lipoid nephrosis)
- Strenuous exercise
- Stress
- Benign orthostatic (postural) proteinuria
- Focal segmental glomerulosclerosis (FSGS)
- IgA nephropathy (i.e. Berger's disease)
- IgM nephropathy
- Membranoproliferative glomerulonephritis
- Membranous nephropathy
- Minimal change disease
- Sarcoidosis
- Alport's syndrome
- Diabetes mellitus (diabetic nephropathy)
- Drugs (e.g. NSAIDs, nicotine, penicillamine, lithium carbonate, gold and other heavy metals, ACE inhibitors, antibiotics, or opiates (especially heroin)
- Fabry's disease
- Infections (e.g. HIV, syphilis, hepatitis, poststreptococcal infection, urinary schistosomiasis)
- Aminoaciduria
- Fanconi syndrome in association with Wilson disease
- Hypertensive nephrosclerosis
- Interstitial nephritis
- Sickle cell disease
- Hemoglobinuria
- Multiple myeloma
- Myoglobinuria
- Organ rejection:
- Ebola virus disease
- Nail patella syndrome
- Familial Mediterranean fever
- HELLP Syndrome
- Systemic lupus erythematosus
- Granulomatosis with polyangiitis
- Rheumatoid arthritis
- Glycogen storage disease type 1
- Goodpasture's syndrome
- Henoch–Schönlein purpura
- A urinary tract infection which has spread to the kidney(s)
- Sjögren's syndrome
- Post-infectious glomerulonephritis
The pathogenesis of this disease is unclear. Arteriosclerosis obliterans has been postulated as the cause, along with errors of the clotting and fibrinolytic pathways such as antiphospholipid syndrome.
Liver transplantation has proven to be effective for ATTR familial amyloidosis due to Val30Met mutation.
Alternatively, a European Medicines Agency approved drug Tafamidis or Vyndaqel now exists which stabilizes transthyretin tetramers comprising wild type and different mutant subunits against amyloidogenesis halting the progression of peripheral neuropathy and autonomic nervous system dysfunction.
Currently there are two ongoing clinical trials undergoing recruitment in the United States and worldwide to evaluate investigational medicines that could possibly treat TTR.
There are three main mechanisms to cause proteinuria:
- Due to disease in the glomerulus
- Because of increased quantity of proteins in serum (overflow proteinuria)
- Due to low reabsorption at proximal tubule (Fanconi syndrome)
Proteinuria can also be caused by certain biological agents, such as bevacizumab (Avastin) used in cancer treatment. Excessive fluid intake (drinking in excess of 4 litres of water per day) is another cause.
Also leptin administration to normotensive Sprague Dawley rats during pregnancy significantly increases urinary protein excretion.
Proteinuria may be a sign of renal (kidney) damage. Since serum proteins are readily reabsorbed from urine, the presence of excess protein indicates either an insufficiency of absorption or impaired filtration. People with diabetes may have damaged nephrons and develop proteinuria. The most common cause of proteinuria is diabetes, and in any person with proteinuria and diabetes, the cause of the underlying proteinuria should be separated into two categories: diabetic proteinuria versus the field.
With severe proteinuria, general hypoproteinemia can develop which results in
diminished oncotic pressure. Symptoms of diminished oncotic pressure may include ascites, edema and hydrothorax.
The familial amyloid neuropathies (or familial amyloidotic neuropathies, neuropathic heredofamilial amyloidosis, familial amyloid polyneuropathy) are a rare group of autosomal dominant diseases wherein the autonomic nervous system and/or other nerves are compromised by protein aggregation and/or amyloid fibril formation.
Primary systemic amyloidosis (AL amyloidosis or just primary amyloidosis) is a disease that involves the mesenchymal tissue, the tongue, heart, gastrointestinal tract, and skin.
Secondary systemic amyloidosis is a condition that involves the adrenal gland, liver, spleen, and kidney as a result of amyloid deposition due to a chronic disease such as Behçet's disease, ulcerative colitis, etc.
The kidney is the organ most frequently affected. Proteinuria, loss of protein in the urine, is characteristic. More than 90% of people with LCDD develop kidney failure, often with rapid progression of disease.
Light chains may be deposited in many other organs and may or may not result in any symptoms. Other than the kidneys, liver and heart are the most commonly involved organs. Deposition of light chains in the liver may lead to hepatomegaly, an enlarged liver, or rarely portal hypertension or liver failure. The heart is affected in up to 80% of patients with LCDD, and may cause arrythmias and congestive heart failure.
Familial Amyloid Cardiomyopathy (FAC), or Transthyretin Amyloid Cardiomyopathy (ATTR-CM) results from the aggregation and deposition of mutant and wild-type transthyretin (TTR) protein in the heart. TTR amyloid fibrils infiltrate the myocardium, leading to diastolic dysfunction from restrictive cardiomyopathy, and eventual heart failure. Both mutant and wild-type transthyretin comprise the aggregates because the TTR blood protein is a tetramer composed of mutant and wild-type TTR subunits in heterozygotes. Several mutations in TTR are associated with FAC, including V122I, V20I, P24S, A45T, Gly47Val, Glu51Gly, I68L, Gln92Lys, and L111M. One common mutation (V122I), which is a substitution of isoleucine for valine at position 122, occurs with high frequency in African-Americans, with a prevalence of approximately 3.5%. FAC is clinically similar to senile systemic amyloidosis, in which cardiomyopathy results from the aggregation of wild-type transthyretin exclusively.