What is amyloidosis?

Amyloidosis is a condition that causes an abnormal protein called amyloid to build up in your body. Amyloid deposits can eventually damage organs and cause them to fail. This condition is rare, but it can be serious.

Organs that amyloidosis can affect include the:

  • heart
  • kidneys
  • intestines
  • joints
  • liver
  • nerves
  • skin
  • soft tissues

Sometimes, amyloid collects throughout your body. This is called systemic, or body-wide, amyloidosis.

Most forms of amyloidosis aren’t preventable. However, you can manage symptoms with treatment. Keep reading to learn more.

What are the symptoms?

In its early stages, amyloidosis might not cause symptoms. When it becomes more severe, which symptoms you have depend on the organ or organs that are affected.

If your heart is affected, you may experience:

  • shortness of breath
  • fast, slow, or irregular heart rate
  • chest pain
  • low blood pressure, which could cause lightheadedness

If your kidneys are affected, you may experience swelling in your legs due to fluid buildup (edema) or foamy urine from excess protein.

If your liver is affected, you may experience pain and swelling in the upper part of your abdomen.

If your gastrointestinal tract is affected, you may experience:

  • nausea
  • diarrhea
  • constipation
  • appetite loss
  • weight loss
  • feeling of fullness right after eating

If your nerves are affected, you may experience:

  • pain, numbness, and tingling in your hands, feet, and lower legs
  • dizziness when standing up
  • nausea
  • diarrhea
  • inability to feel cold or heat

General symptoms that can occur include:

  • fatigue
  • weakness
  • bruising around your eyes or on your skin
  • swollen tongue
  • joint pain
  • carpal tunnel syndrome, or numbness and tingling in your hands and thumb

If you experience any of these symptoms for more than a day or two, see your doctor.

What are the types and causes?

Your bone marrow normally produces the blood cells your body uses to transport oxygen to your tissues, fight infections, and help your blood clot.

In one type of amyloidosis, infection-fighting white blood cells (plasma cells) in the bone marrow produce an abnormal protein called amyloid. This protein folds and clumps, and is harder for the body to break down.

In general, amyloidosis is caused by a buildup of amyloid in your organs. How the amyloid gets there depends on which type of the condition you have:

Light chain (AL) amyloidosis: This is the most common type. It happens when abnormal amyloid proteins called light chains build up in organs like your heart, kidneys, liver, and skin. This type used to be called primary amyloidosis.

Autoimmune (AA) amyloidosis: You can get this type after an infection like tuberculosis, or a disease that causes inflammation such as rheumatoid arthritis or inflammatory bowel disease. About half of people with AA amyloidosis have rheumatoid arthritis. AA amyloidosis mainly affects your kidneys. Sometimes it also can damage your intestines, liver, or heart. This type used to be called secondary amyloidosis.

Dialysis-related amyloidosis: This type affects people who are on dialysis for a long period of time as a result of kidney problems. The amyloid deposits in the joints and tendons, causing pain and stiffness.

Hereditary (familial) amyloidosis: This rare type is caused by a mutation in a gene that runs in families. Hereditary amyloidosis can affect the nerves, heart, liver, and kidneys.

Senile amyloidosis: This type affects the heart in older men.

Who is at risk?

Although anyone can get amyloidosis, certain factors increase your risk.

These include:

  • Age: Most people are diagnosed with the most common type, AL amyloidosis, at age 50 or older.
  • Gender: Men account for almost 70 percent of amyloidosis cases.
  • Race: African-Americans are at greater risk for hereditary amyloidosis than other races.
  • Family history: Hereditary amyloidosis runs in families.
  • Medical history: Having an infection or inflammatory disease makes you more likely to get AA amyloidosis.
  • Kidney health: If your kidneys are damaged and you need dialysis, you may be at increased risk. Dialysis may not remove big proteins from your blood as effectively as your own kidneys can.

How is it diagnosed?

Your doctor will ask about your symptoms and medical history. It’s important to tell your doctor as much as you can, because amyloidosis symptoms can be similar to those of other conditions. Misdiagnosis is common.

Your doctor may use the following tests to help make a diagnosis:

Blood and urine tests: These tests can be done to assess amyloid protein levels. Blood tests can also check your thyroid and liver function.

Echocardiogram: This imaging test uses sound waves to create pictures of your heart.

Biopsy: For this test, a doctor removes a sample of tissue from your liver, nerves, kidneys, heart, abdominal fat, or other organs. Analyzing the piece of tissue can help your doctor figure out what type of amyloid deposit you have.

Bone marrow aspiration and biopsy: Bone marrow aspiration uses a needle to remove a small amount of fluid from inside your bones. A bone marrow biopsy removes some of the tissue from inside your bone. These tests may be done together or separately. The samples are sent to a lab, where they’re checked for abnormal cells.

If a diagnosis is made, your doctor will figure out which type you have. This can be done with tests like immunochemical staining and protein electrophoresis.

How is it treated?

Amyloidosis isn’t curable. Treatment aims to slow amyloid protein production and reduce symptoms.

General treatments

These medicines are used to control amyloidosis symptoms:

  • pain relievers
  • drugs to manage diarrhea, nausea, and vomiting
  • diuretics to reduce fluid buildup in your body
  • blood thinners to prevent blood clots
  • medicines to control your heart rate

Other treatments are based on the type of amyloidosis you have.

AL amyloidosis

This type is treated with chemotherapy. These drugs are usually used to treat cancer, but in amyloidosis they destroy the abnormal blood cells that produce amyloid protein. After you have chemotherapy, you might have a stem cell/bone marrow transplant to replace the damaged bone marrow cells.

Other drugs you might get to treat Al amyloidosis include:

Proteasome inhibitors: These drugs block substances called proteasomes, which break down proteins.

Immunomodulators: These medicines dampen an overactive immune system response.

AA amyloidosis

This type is treated based on the cause. Bacterial infections are treated with antibiotics. Inflammatory conditions are treated with medicines to bring down inflammation.

Dialysis-related amyloidosis

You can treat this type by changing the type of dialysis you get. Another option is to have a kidney transplant.

Hereditary amyloidosis

Because the abnormal protein that causes this type is made in your liver, you may need a liver transplant.

What complications can it cause?

Amyloidosis can potentially damage any organ in which it builds up:

Heart damage: Amyloidosis interrupts your heart’s electrical system, and makes it harder for your heart to beat effectively. Amyloid in the heart causes stiffness and weakening of the pumping action of the heart leads to shortness of breath and low blood pressure. Eventually you could develop heart failure.

Kidney damage: Damage to the filters inside your kidneys can make it harder for these bean-shaped organs to remove wastes from your blood. Eventually, your kidneys will become overworked, and you could develop kidney failure.

Nerve damage: When amyloid builds up in nerves and damages them, you might feel sensations like numbness or tingling in your fingers and toes. This condition can also affect other nerves — like the ones that control your bowel function or blood pressure.

What can you expect?

Amyloidosis isn’t curable, but you can manage it and control amyloid levels with treatment. Talk to your doctor about your treatment options, and work with them if you find that your current treatment plan isn’t doing what it should. They can make adjustments as needed to help reduce your symptoms and improve your quality of life.