Amyloidosis (am-uh-loi-DO-sis) is a rare disease that occurs when a substance called amyloid builds up in your organs. Amyloid is an abnormal protein that is produced in your bone marrow and can be deposited in any tissue or organ.
Amyloidosis can affect different organs in different people, and there are different types of amyloid. Amyloidosis frequently affects the heart, kidneys, liver, spleen, nervous system and digestive tract. Severe amyloidosis can lead to life-threatening organ failure.
There's no cure for amyloidosis. But treatments can help you manage your symptoms and limit the production of amyloid protein.
You may not experience signs and symptoms of amyloidosis until the condition is advanced. When signs and symptoms are evident, they depend on which of your organs are affected.
Signs and symptoms of amyloidosis may include:
- Swelling of your ankles and legs
- Severe fatigue and weakness
- Shortness of breath
- Numbness, tingling or pain in your hands or feet, especially pain in your wrist (carpal tunnel syndrome)
- Diarrhea, possibly with blood, or constipation
- Unintentional, significant weight loss
- An enlarged tongue
- Skin changes, such as thickening or easy bruising, and purplish patches around the eyes
- An irregular heartbeat
- Difficulty swallowing
When to see a doctor
See your doctor if you persistently experience any of the signs or symptoms associated with amyloidosis.
In general, amyloidosis is caused by the buildup of an abnormal protein called amyloid. Amyloid is produced in your bone marrow and can be deposited in any tissue or organ. The specific cause of your condition depends on the type of amyloidosis you have.
There are several types of amyloidosis, including:
- AL amyloidosis (immunoglobulin light chain amyloidosis) is the most common type and can affect your heart, kidneys, skin, nerves and liver. Previously known as primary amyloidosis, AL amyloidosis occurs when your bone marrow produces abnormal antibodies that can't be broken down. The antibodies are deposited in your tissues as amyloid, interfering with normal function.
- AA amyloidosis mostly affects your kidneys but occasionally your digestive tract, liver or heart. It was previously known as secondary amyloidosis. It occurs along with chronic infectious or inflammatory diseases, such as rheumatoid arthritis or inflammatory bowel disease.
- Hereditary amyloidosis (familial amyloidosis) is an inherited disorder that often affects the liver, nerves, heart and kidneys. Many different types of gene abnormalities present at birth are associated with an increased risk of amyloid disease. The type and location of an amyloid gene abnormality can affect the risk of certain complications, the age at which symptoms first appear, and the way the disease progresses over time.
- Dialysis-related amyloidosis develops when proteins in blood are deposited in joints and tendons — causing pain, stiffness and fluid in the joints, as well as carpal tunnel syndrome. This type generally affects people on long-term dialysis.
Anyone can develop amyloidosis. Factors that increase your risk include:
- Age. Most people diagnosed with AL amyloidosis, the most common type, are between ages 60 and 70, although earlier onset occurs.
- Sex. Nearly 70 percent of people with AL amyloidosis are men.
- Other diseases. Having a chronic infectious or inflammatory disease increases your risk of AA amyloidosis.
- Family history. Some types of amyloidosis are hereditary.
- Kidney dialysis. Dialysis can't always remove large proteins from the blood. If you're on dialysis, abnormal proteins can build up in your blood and eventually be deposited in tissue. This condition is less common with modern dialysis techniques.
- Race. People of African descent appear to be at higher risk of carrying a genetic mutation associated with the type of amyloidosis that can harm the heart.
The potential complications of amyloidosis depend on which organs the amyloid deposits affect. Amyloidosis can seriously damage your:
- Kidneys. Amyloid can harm the kidneys' filtering system, causing protein to leak from your blood into your urine. The kidneys' ability to remove waste products from your body is lowered, which may eventually lead to kidney failure.
- Heart. Amyloid reduces your heart's ability to fill with blood between heartbeats. Less blood is pumped with each beat, and you may experience shortness of breath. If amyloidosis affects your heart's electrical system, your heart rhythm may be disturbed.
Nervous system. You may experience pain, numbness or tingling of the fingers or numbness, lack of feeling or a burning sensation in your toes or the soles of your feet. If amyloid affects the nerves that control your bowel function, you may experience periods of alternating constipation and diarrhea.
If the condition affects nerves that control blood pressure, you may experience dizziness or near fainting when standing too quickly.
Amyloidosis is often overlooked because the signs and symptoms can mimic those of more-common diseases. Diagnosis as early as possible can help prevent further organ damage. Precise diagnosis is important because treatment varies greatly, depending on your specific condition.
Your doctor is likely to start with a thorough medical history and physical exam. After that, you may have:
- Laboratory tests. Your blood and urine may be analyzed for abnormal protein that can indicate amyloidosis. Depending on your signs and symptoms, you may also have thyroid and liver function tests.
- Biopsy. A tissue sample may be taken and checked for signs of amyloidosis. The biopsy may be taken from your abdominal fat, bone marrow, or an organ such as your liver or kidney. Tissue analysis can help determine the type of amyloid deposit.
- Imaging tests. Images of the organs affected by amyloidosis can help establish the extent of your disease. Echocardiogram may be used to assess the size and functioning of your heart. Other imaging tests can evaluate the extent of amyloidosis in your liver or spleen.
There's no cure for amyloidosis. But treatment can help manage signs and symptoms and limit further production of amyloid protein. Specific treatments depend on the type of amyloidosis and target the source of the amyloid production.
AL amyloidosis. Many of the same chemotherapy medications that treat multiple myeloma are used in AL amyloidosis to stop the growth of abnormal cells that produce amyloid.
Autologous blood stem cell transplant (ASCT) offers an additional treatment option in some cases. This procedure involves collecting your own stem cells from your blood and storing them for a short time while you have high-dose chemotherapy. The stem cells are then returned to your body via a vein.
ASCT is most appropriate for people whose disease isn't advanced and whose heart isn't greatly affected.
- AA amyloidosis. Treatments target the underlying condition — for example, an anti-inflammatory medication to treat rheumatoid arthritis.
- Hereditary amyloidosis. Liver transplantation may be an option because the protein that causes this form of amyloidosis is made in the liver.
- Dialysis-related amyloidosis. Treatments include changing your mode of dialysis or having a kidney transplant.
To manage ongoing signs and symptoms of amyloidosis, your doctor also may recommend:
- Pain medication
- Fluid retention medication (diuretic) and a low-salt diet
- Blood-thinning medication
- Medication to control your heart rate
These tips can help you live with amyloidosis:
- Pace yourself. If you feel short of breath, take a break. You'll need to avoid strenuous activities, but you may be able to continue normal daily activities, such as going to work. Talk to your doctor about an appropriate level of activity for you.
- Eat a balanced diet. Good nutrition is important to provide your body with adequate energy. Follow a low-salt diet if your doctor recommends it.
A diagnosis of amyloidosis can be extremely challenging. Here are some suggestions that may make dealing with amyloidosis easier:
- Find someone to talk with. You may feel comfortable discussing your feelings with a friend or family member, or you might prefer meeting with a formal support group.
- Set reasonable goals. Having goals helps you feel in control and can give you a sense of purpose. Choose goals you can reach.
You may be referred to a doctor who specializes in blood disorders (hematologist).
What you can do
- Write down your symptoms, including any that may seem unrelated to the reason why you scheduled the appointment.
- Make a list of all your medications, vitamins and supplements.
- Write down your key medical information, including other conditions.
- Write down key personal information, including any recent changes or stressors in your life.
- Write down questions to ask your doctor.
- Ask a relative or friend to accompany you, to help you remember what the doctor says.
Questions to ask your doctor
- What's the most likely cause of my symptoms?
- What type of amyloidosis do I have?
- What organs are affected?
- What stage am I?
- What kinds of tests do I need?
- What kind of treatments do I need?
- Am I at risk of long-term complications?
- What types of side effects can I expect from treatment?
- Do I need to follow any dietary or activity restrictions?
- I have another health condition. How can I best manage them together?
In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask other questions during your appointment.
What to expect from your doctor
Your doctor is likely to ask you a number of questions. Being ready to answer them may provide time to go over points you want to spend more time on. You may be asked:
- When did you first begin experiencing symptoms? How severe are they, and are they continuous or occasional?
- Does anything seem to make your symptoms better or worse?
- How is your appetite? Have you recently lost weight without trying?
- Have you experienced any leg swelling?
- Have you experienced shortness of breath?
- Are you able to work and perform normal daily tasks? Are you often tired?
- Have you noticed that you bruise easily?
- Has anyone in your family ever been diagnosed with amyloidosis?