Amyloidosis is a potentially serious and very rare disease that involves abnormal protein (amyloid) building up in your tissues and organs.
Seattle Cancer Care Alliance (SCCA) offers collaborative amyloidosis treatment from a team of experts who can address the wide range of health care needs you may have.
- What is amyloidosis?
- Types of amyloidosis
- What causes amyloidosis?
- How common is amyloidosis?
- Support and research
- Next steps
What is amyloidosis?
In amyloidosis, protein deposits can build up throughout your body, causing a broad spectrum of symptoms. It can lead to organ failure, which may be fatal.
- Most often, amyloidosis affects tissues and organs (such as the kidneys, heart and nerves) throughout the body (systemic disease).
- In some people, the condition is limited to a single tissue or organ, such as the lungs, skin, bladder or bowel (localized disease).
- Amyloidosis isn’t cancer, but it can be associated with certain blood cancers, like multiple myeloma and Waldenström macroglobulinemia.
Types of amyloidosis
There are many types of amyloidosis. These are some of the major types.
Primary amyloidosis is also called light chain amyloidosis (AL). It occurs on its own, not as the result of another illness.
- The plasma cells in your bone marrow become abnormal and produce too much of a protein called the light chain, which is part of an antibody.
- Deposits of this protein typically affect the heart, kidneys, nerves and gastrointestinal (GI) system.
- AL is the most common type of amyloidosis in the U.S.
Secondary amyloidosis is also called inflammatory amyloidosis or reactive amyloidosis (AA). It results from another condition, such as rheumatoid arthritis, chronic infection (like tuberculosis), inflammatory bowel disease or diabetes.
- AA is rare in the U.S. and more common in developing countries, where the underlying condition is more likely to go untreated.
- It happens when a protein called serum amyloid A (SAA) builds up, typically in the spleen, liver, kidneys, adrenal glands and lymph nodes.
Familial amyloidosis is also called hereditary amyloidosis or ATTRm, for the transthyretin (TTR) gene that causes it. This type is passed down in families.
- The symptoms and severity can vary.
- Complications of ATTRm happen from abnormal TTR protein being deposited in organs — often the heart, nervous system and GI system.
- Within ATTRm, there are many possible variations, linked with more than 100 different TTR mutations. Val30Met is one of the most prevalent ATTRm mutations in the world. Another example is a genetic variation called Val122Ile, which primarily affects African-Americans and usually causes cardiac deposits.
Other, less common, types of hereditary amyloidosis are caused by mutations in different genes, not TTR. One example is apolipoprotein amyloidosis (ApoAI).
This type of amyloidosis affects older men. It used to be called senile amyloidosis, but doctors no longer use this term. Wild-type TTR (ATTRwt) causes amyloid deposits throughout the body, but it particularly affects the heart, where it can cause an irregular heart rhythm (atrial fibrillation) and congestive heart failure.
Symptoms of amyloidosis
The signs and symptoms of amyloidosis can vary widely depending on how many organs and which organs are affected by protein deposits. Some people don't have symptoms at all or don't have them until the disease is advanced.
Here are a few examples of the range of possible symptoms.
- Shortness of breath
- Abnormal heart rhythm
- Chest pain
- Worsening difficulty with physical activity
- Foamy urine or decreased urine output
- Swelling in the lower legs, belly, arms and lungs
- Pain, numbness or tingling in the hands or feet (examples of peripheral neuropathy)
- Dizziness when standing quickly, erectile dysfunction or bowel problems (examples of autonomic neuropathy)
- Carpal tunnel syndrome
- Diarrhea or constipation
- Unexplained weight loss or loss of appetite
- Thickened tongue (macroglossia)
- Gastroesophageal reflux disease
Amyloidosis can be difficult to diagnose because it’s such a rare disease and the signs and symptoms may be similar to many other more common conditions.
The average hematologist-oncologist in the community may see only one or two people with amyloidosis in their entire career. Unfortunately, it’s fairly common for patients to visit several doctors over many months before being accurately diagnosed.
To diagnose your condition:
- Your doctor will examine you and ask about your signs, symptoms and medical history. They’ll also take into account your age, your family’s medical history and results of any tests you’ve already had.
- You will have blood and urine tests to look for abnormal proteins.
- You will need a bone marrow aspiration and biopsy (using a needle to remove samples of liquid and solid marrow) or a biopsy of other affected tissue (such as fat), which a pathologist will examine under a microscope.
If you have already had these tests or procedures at another facility, we may ask for your specimens to be sent here for a thorough review.
Researchers at SCCA are working to develop our own mass spectrometric analysis for amyloidosis — the lab studies needed to diagnosis the condition and identify the type.
Additional tests, like an ultrasound, electrocardiogram or echocardiogram, can help your team understand how amyloidosis is affecting your body.
What causes amyloidosis?
There are many different causes of amyloidosis. In the most common type, light chain amyloidosis, plasma cells in your bone marrow become abnormal and secrete an abnormal protein into your blood that can build up in your heart, kidneys, nerves and other organ systems.
Amyloidosis is more common after age 40 and more common in men than women. In some people it is linked with another disease, such as multiple myeloma.
The familial form runs in families.
Most people with amyloidosis have no known risk factors.
How common is amyloidosis?
Doctors estimate about 4,000 people develop primary amyloidosis in the U.S. each year, but it’s difficult to say because the disease often goes undiagnosed or the diagnosis is delayed. Secondary amyloidosis and familial amyloidosis are much less common.
Support can be especially helpful when you have an uncommon condition, like this one. The Amyloidosis Support Groups and Amyloidosis Foundation websites can help connect you with support in the Pacific Northwest or around the country.
Support and research
Support can be especially helpful when you have an uncommon condition, like this one. The Amyloidosis Support Group and Amyloidosis Foundation can help connect you with support in the Pacific Northwest or around the country. The Amyloidosis Research Consortium is a leading organization fostering research into this disease.