Amyloidosis is a condition where an abnormal protein is deposited in different organs in the body. It can affect the heart, kidneys, spleen, nervous system, skin and digestive tract.
There are many different types of amyloidosis. Most commonly, it is caused by a blood cell cancer – like multiple myeloma or lymphoma. It may also be an inherited condition, and can sometimes be related to inflammatory conditions like rheumatoid arthritis.
What are the symptoms?
The symptoms of amyloidosis depend on which organ is affected.
When the heart is affected, the amyloid proteins make the heart stiff and unable to relax properly. This results in fluid retention and symptoms of heart failure – like shortness of breath, fatigue and swelling. Sometimes amyloidosis can affect the electrical conduction system of the heart, causing abnormally fast or slow heart rhythms.
How is it diagnosed?
Cardiac amyloidosis is often suspected based on abnormalities on the ECG and echocardiogram.
Other tests like a coronary angiogram or cardiac MRI may be helpful, however, in order to confirm the diagnosis a tissue biopsy is needed. Ideally, a biopsy is taken from one of the organs involved. More commonly, a sample of fat is analyzed, called a fat pad biopsy. Other tests, like a bone marrow biopsy, may be considered if there is a suspicion that the amyloidosis is related to a blood cell cancer.
How is it treated?
The treatment varies depending on the type of amyloidosis.
If the amyloidosis is due to a blood cancer, then chemotherapy is the usual treatment. If the abnormal protein is being produced by the liver, sometimes a liver transplant is considered.
Other treatments are aimed at controlling the symptoms of heart failure by regulating the amount of fluid in the body. This involves salt and fluid restriction and also diuretics (water pills).
There are a number of treatments that are currently being tested, and will hopefully improve the symptoms and life expectancy of people with cardiac amyloidosis.