Amyloidosis

What is amyloidosis?

Amyloidosis is a disease in which abnormal proteins collect and build up in an organ or tissue. This collection of proteins is known as an amyloid, and can form in different ways.

Amyloid Light Chain (AL)

AL is the most common form in the United States. It results from the formation of abnormal plasma cells produced in the bone marrow. Instead of producing helpful antibodies, these cells create abnormal antibodies which enter the bloodstream and are deposited in organs and other tissues. These are amyloid protein deposits.

AL amyloidosis is more common among men than women, and typically affects older populations, over the age of 50.

Amyloid Serum A Protein (AA or SAA)

AA begins with an infection or inflammatory disease. This infection or inflammation can lead to the production of proteins which are deposited in organs or tissues, forming an amyloid formation.

Amyloid Transthyretin (ATTR)

Unlike other forms of amyloidosis, ATTR is a hereditary condition. Certain gene mutations can lead to the production of abnormal transthyretin proteins. These proteins are carried through the blood and deposited in organs and tissues, leading to amyloidosis.

Symptoms of amyloidosis

Amyloids can develop in different areas of the body, so amyloidosis symptoms can vary. In addition to organ-specific symptoms, amyloidosis can cause general fatigue, weight loss, joint swelling, and soft tissue bruising.

Kidney-related amyloidosis symptoms

Initially, protein deposits in the kidneys can hamper their ability to filter the blood. As the condition worsens, it may lead to nephrotic syndrome. This condition can cause notable symptoms such as swelling of the legs and ankles, as well as general symptoms like fatigue, nausea, and loss of appetite.

Amyloidosis can progress to significant damage to the kidneys, including kidney failure.

Heart-related amyloidosis symptoms

Protein buildup in the heart muscle tissues can cause them to thicken and stiffen, making the heart function less efficiently. This can lead to feelings of weakness and fatigue, tightness in the chest, and shortness of breath from minimal exercise or exertion.

Amyloidosis may also affect the electrical processes of the heart, which help regulate the heartbeat. This interference can cause the heartrate to speed up or slow down regardless of physical activity.

Amyloidosis symptoms of the digestive system

Amyloid formations in the digestive system can mimic the symptoms of other digestive diseases, such as:

• Nausea
• Loss of appetite
• Diarrhea
• Constipation
• Swollen tongue

It is important to consult with your physician if you are experiencing these and/or other such symptoms. The sooner amyloidosis treatment can begin, the better the prognosis.

Amyloidosis symptoms of the nervous system

Amyloidosis can directly affect the nerves of the body, causing a variety of symptoms. This may affect the hands and feet, legs, or nerves that help regulate regular bodily functions like the heartrate. These conditions are known as peripheral neuropathy and autonomic neuropathy, respectively.

A wide range of nervous system symptoms may be present:

• Pain
• Numbness or tingling sensations
• Loss of temperature sensitivity
• Blood pressure or heartrate fluctuations
• Dizziness when standing quickly

Other nonspecific amyloidosis symptoms may appear

• Fatigue and bodily weakness
• Excessive weight loss
• Bruising around the eyes
• Bruising of soft tissues and skin folds
• Joint swelling

Diagnosing amyloidosis

Lab tests are used to diagnose amyloidosis, measure its severity, and monitor its progression and response to treatment.

Blood and urine tests can detect the presence of amyloid proteins, but cannot give a conclusive diagnosis. A bone marrow test or tissue biopsy can be completed to confirm the diagnosis.

Following a confirmed diagnosis, blood and urine tests may be repeated to monitor the amount of abnormal protein being produced by the plasma cells. In particular, a free light chain assay may be done to monitor the levels of free light chains in the blood to track the progress of treatment, or to test for stability of the condition between treatments.

A tissue biopsy may be used to positively identify amyloidosis, as well as test whether an area is affected or not. Biopsy samples may be taken from organs or soft tissue such as fat cells in the abdomen. These samples are examined with a microscope to look for amyloid protein deposits.

Bone marrow aspirates and biopsies look at the percentage of abnormal plasma cells in the marrow which produce amyloid proteins. This can help determine the extent of the condition, as well as inform the treatment protocols.

When an amyloid in the heart is suspected, an echocardiogram may be ordered. This will help determine the amyloid's impact on the heart's function.

Amyloidosis treatment options

Standard treatment for amyloidosis comes in two parts: preventing the disease's progression and helping to lessen its symptoms.

Autologous stem cell transplantation is the standard treatment to prevent the disease’s progression. This aims to reduce the amount of abnormal proteins in the blood to near zero to stop the growth of amyloidosis deposits. The transplantation helps prevent the formation of new proteins, while the use of steroids or other medication may help eliminate the abnormal plasma cells which produce the proteins.

Chemotherapy, inhibitors, and immunomodulatory drugs may also be used.

Supportive treatment is used to improve quality of life with amyloidosis. These treatments target specific symptoms of amyloidosis. Supportive medications and treatments may include:

• Special diets and nutritional counseling
• Anti-nausea medication
• Blood pressure medication
• Dialysis

What are the chances of complete recovery from amyloidosis?

While complete remission—the absence of abnormal proteins in the bloodstream—is relatively high, occurring in over half of patients seeking amyloidosis treatment, recovery is different for each individual.

As amyloidosis can affect many different parts of the body, including different organs, every prognosis is unique. The length of time between the development of amyloidosis and the beginning of treatment can also have a large impact.

If you have been diagnosed with amyloidosis, it is important to speak with a specialist right away to discuss your personalized treatment options.

At UI Health Care, our multidisciplinary team includes oncologists, nephrologists, cardiologists, and other specialists to treat all aspects of amyloidosis.