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.

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.

This disease is endemic in Portuguese locations Póvoa de Varzim and Vila do Conde (Caxinas), with more than 1000 affected people, coming from about 500 families, where 70% of the people develop the illness. ll the analysed Portuguese families presented the same haplotype (haplotype I) associated with the Met 30 mutation. In northern Sweden, more specifically Piteå, Skellefteå and Umeå, 1.5% of the population has the mutated gene. There are many other populations in the world who exhibit the illness after having developed it independently.

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.

Familial amyloid polyneuropathy (FAP), also called transthyretin-related hereditary amyloidosis, transthyretin amyloidosis abbreviated also as ATTR (hereditary form), or Corino de Andrade's disease, is an autosomal dominant neurodegenerative disease. It is a form of amyloidosis, and was first identified and described by Portuguese neurologist Mário Corino da Costa Andrade, in 1952. FAP is distinct from senile systemic amyloidosis (SSA), which is not inherited, and which was determined to be the primary cause of death for 70% of supercentenarians who have been autopsied.

FAP can be ameliorated by liver transplantation.

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.

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.

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.

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.

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

Amyloidosis is a group of diseases in which abnormal protein, known as amyloid fibrils, builds up in tissue. Symptoms depend on the type and are often variable. They may include diarrhea, weight loss, feeling tired, enlargement of the tongue, bleeding, numbness, feeling faint with standing, swelling of the legs, or enlargement of the spleen.

There are about 30 different types of amyloidosis, each due to a specific protein misfolding. Some are genetic while others are acquired. They are grouped into localized and systemic forms. The four most common types of systemic disease are light chain (AL), inflammation (AA), dialysis (AβM), and hereditary and old age (ATTR).

Diagnosis may be suspected when protein is found in the urine, organ enlargement is present, or problems are found with multiple peripheral nerves and it is unclear why. Diagnosis is confirmed by tissue biopsy. Due to the variable presentation, a diagnosis can often take some time to reach.

Treatment is geared towards decreasing the amount of the involved protein. This may sometimes be achieved by determining and treating the underlying cause. AL amyloidosis occurs in about 3–13 per million people per year and AA amyloidosis in about 2 per million people per year. The usual age of onset of these two types is 55 to 60 years old. Without treatment, life expectancy is between six months and four years. In the developed world about 1 per 1,000 people die from amyloidosis. Amyloidosis has been described since at least 1639.

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.

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.

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 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 .

Wild-type transthyretin amyloid accumulates mainly in the heart, where it causes stiffness and often thickening of its walls, leading consequently to shortness of breath and intolerance to exercise, called diastolic dysfunction. Excessively slow heart rate can also occur, such as in sick sinus syndrome, with ensuing fatigue and dizziness. Wild-type transthyretin deposition is also a common cause of carpal tunnel syndrome in elderly men, which may cause pain, tingling and loss of sensation in the hands. Some patients may develop carpal tunnel syndrome as an initial symptom of wild-type transthyretin amyloid.

There appears to be an increase in the risk for developing hematuria or blood in the urine due to urological lesions.

Amyloid cardiomyopathy (stiff heart syndrome) is associated with the systemic production and release of many amyloidogenic proteins, especially immunoglobulin light chain or transthyretin (TTR). It can be characterized by the extracellular deposition of amyloid in the heart. Amyloids are foldable proteins that all stick together to build fibrils.

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).

Inclusion body myositis (IBM) is an inflammatory muscle disease characterized by slowly progressive weakness and wasting of both distal and proximal muscles, most apparent in the muscles of the arms and legs. There are two types: sporadic inclusion body myositis (sIBM), which is more common, and hereditary inclusion body myopathy (hIBM).

In sporadic inclusion body myositis [MY-oh-sigh-tis], two processes, one autoimmune and the other degenerative, appear to occur in the muscle cells in parallel. The inflammation aspect is characterized by the cloning of T cells that appear to be driven by specific antigens to invade muscle fibers. The degeneration aspect is characterized by the appearance of holes in the muscle cell vacuoles, deposits of abnormal proteins within the cells and in filamentous inclusions (hence the name inclusion body myositis).

Weakness comes on slowly (over months or years) and progresses steadily and usually leads to severe weakness and wasting of arm and leg muscles. It is more common in men than women. Patients may become unable to perform activities of daily living and most require assistive devices within 5 to 10 years of symptom onset. sIBM is not considered a disorder, but the risk of serious injury due to falls is increased. One common and potentially fatal complication is dysphagia. There is no effective treatment for the disease.

sIBM is a rare yet increasingly prevalent disease and is the most common cause of inflammatory myopathy in people over age 50. Recent research from Australia indicates that the incidence of IBM varies in different populations and ethnic groups. The authors found that the current prevalence was 14.9 per million in the overall population, with a prevalence of 51.3 per million population in people over 50 years of age. As seen in these numbers, sIBM is an age-related disease – its incidence increases with age and symptoms usually begin after 50 years of age. It is the most common acquired muscle disorder seen in people over 50, although about 20% of cases display symptoms before the age of 50.

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.

sIBM is not inherited and is not passed on to the children of IBM patients. There are genetic features that do not directly cause IBM but that appear to predispose a person to getting IBM — having this particular combination of genes increases one's susceptibility to getting IBM. Some 67% of IBM patients have a particular combination of human leukocyte antigen genes in a section of the 8.1 ancestral haplotype in the center of the MHC class II region. sIBM is not passed on from generation to generation, although the susceptibility region of genes may be.

There are also several rare forms of hereditary inclusion body myopathy that are linked to specific genetic defects and that are passed on from generation to generation. Since these forms do not show features of muscle inflammation, they are classified as myopathies rather than forms of myositis. Because they do not display inflammation as a primary symptom, they may in fact be similar, but different diseases to sporadic inclusion body myositis. There are several different types, each inherited in different ways. See hereditary inclusion body myopathy.

A 2007 review concluded there is no indication that the genes responsible for the familial or hereditary conditions are involved in sIBM.

There is no standard treatment for LCDD. High-dose melphalan in conjunction with autologous stem cell transplantation has been used in some patients. A regimen of bortezomib and dexamethasone has also been examined.

Heredofamilial amyloidosis is an inherited condition that may be characterized by systemic or localized deposition of amyloid in body tissues.

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.

It is associated with LAMP2. The status of this condition as a GSD has been disputed.