Symptoms vary widely from person to person and depending on which organs are affected. Some people do not even have symptoms, which makes the condition difficult to diagnose.
When amyloidosis is associated with another disease, symptoms may be masked. The underlying disease may be fatal before amyloidosis is found.
- An enlarged liver
- An enlarged tongue (macroglossia)
- An irregular heartbeat
- Diarrhea alternating with constipation
- Difficulty swallowing
- Dizziness or feeling faint
- Loss of weight
- Numbness or tingling in the hands or feet
- Severe fatigue
- Shortness of breath
- Skin changes
- Swelling of the ankles and legs
The severity of amyloidosis depends on which organs it affects. It can be life threatening if it causes kidney or heart failure.
If the amyloidosis affects the kidneys, their ability to filter the blood becomes impaired. Protein leaks from the blood into the urine. The loss of protein from the blood can cause fluid to leak out of the blood vessels, resulting in swelling in the feet, ankles and calves. Eventually, there is so much damage to the kidneys that they are not able to remove waste products from the body and they fail.
If amyloidosis affects the heart, the first symptom typically is shortness of breath even with only light activity. Climbing a flight of stairs or walking long distances may be difficult without having to stop. The buildup of amyloid in the heart lessens its ability to fill up with blood between heartbeats. As a result, less blood is pumped with each beat, and the heart is not able to keep up with the body's needs. The buildup of amyloid can also cause problems with the electrical system of the heart, resulting in irregular heartbeats (arrhythmia).
Other effects of amyloidosis include:
- A burning sensation as a result of nerves being irritated by the amyloid
- Alternating bouts of constipation and diarrhea, if the protein deposits affect the nerves that control the bowels
- Bowel obstruction
- Carpal tunnel syndrome, which causes pain, numbness or tingling in the fingers. Approximately four out of 10 people with amyloidosis develop this syndrome.
- Disruption of the nervous system
- Dizziness or nearly fainting when standing up too quickly. This can happen if the condition affects the nerves that control blood pressure and a sudden drop in blood pressure occurs when standing up.
- Numbness or lack of feeling in the toes or feet
- Weakness in the legs, which can be a result of nerves irritated by the amyloid
Diseases that are associated with amyloidosis include multiple myeloma, Hodgkin's disease, some types of tumors and Mediterranean fever that runs in families. It may also be associated with aging. Amyloid is often found in the pancreas of people who develop diabetes as adults.
Causes and Risk Factors
The cause for amyloid to be produced and to collect in the tissues is not known. The risk of getting amyloidosis is not connected to what a person eats (including how much protein) or does for a living or to the amount of stress in one's life
The disease starts in the bone marrow. Bone marrow creates red and white blood cells, platelets and antibodies that protect the body against infection. After the antibodies have done their work, the body breaks them down. When the bone marrow cells produce antibodies that cannot be broken down, amyloidosis develops. The antibodies build up in the blood and eventually get deposited in the tissues as amyloid.
The risk of developing amyloidosis is greater in people who:
- Are older than 50
- Have a chronic infection or inflammatory disease
- Have a family history of amyloidosis
- Have multiple myeloma. Between 10 and 15% of people who have multiple myeloma develop amyloidosis.
- Have a kidney disease that has required dialysis for more than five years