Treatment Options for Four Types of Amyloidosis
Amyloidosis is a rare disease that occurs when amyloid, a type of protein, builds up in the organs. This protein is produced in the bone marrow and can deposit in any organ or tissue. Statistics show that at least 4,000 people develop the condition in our country. It is usually diagnosed between the ages of 50 and 65. Although the disease can affect any part of the body, it mostly affects the heart, kidneys, liver, spleen, and the digestive tract, and severe amyloidosis can even result in organ failure.
Here are some of the main types of the disease based on particular symptoms:
Primary amyloidosis (AL)
The most common type, it is an acquired plasma cell disorder in which a monoclonal immunoglobin chain of protein is overproduced in the bone marrow. Primary amyloidosis (AL) is usually found in blood and urine and occurs with Waldenstrom’s macroglobulinemia, lymphoma, or, multiple myeloma. The “AL” in primary amyloidosis refers to light chains. People suffering from this type of the disease usually experience heart failure, protein in the urine, an enlarged liver, kidney failure, and an enlarged tongue.
Treating primary amyloidosis : The type of treatment provided to the patient is based on the progression of the disease. The treatment plans are three-fold:
- Supportive treatment : It refers to treating the symptoms and organ damage. Supportive treatment is helpful for treating conditions like cardiac and renal (kidney) problems that might arise due to the disease, and the main aim is to improve the quality of life.
- Source treatment : The main aim of this treatment is to stop or slow down the overproduction of amyloid at its source. It is often the most preferred treatment option in our country because it provides long-term treatment for the underlying disease.
- Combination therapy : Many patients have benefited from this type of therapy. The recent development of a new strain of medicines works effectively on the abnormal plasma cells causing AL amyloidosis, and the dosage depends on individual patients. Medicines range from traditional chemotherapy medicines, proteasome inhibitors, and immunomodulators.
Secondary amyloidosis (AA)
This type of the condition is caused by inflammatory diseases like familial Mediterranean fever, rheumatoid arthritis, granulomatous ileitis, or other chronic infections. Secondary amyloidosis usually begins in the kidney, but other organs can also be affected. The AA in secondary amyloidosis refers to the AA proteins that are deposited in the organs in the form of fibrils.
Treating secondary amyloidosis (AA) : Currently, there are very few options that directly target the amyloid deposits in the case of secondary amyloidosis (AA). The main aim in treating this type of the disease is to reduce the circulating levels of the precursor protein causing inflammatory conditions like rheumatoid arthritis and renal diseases. Biological agents like anti-TNF (tumor necrosis factor) and (interleukin) IL-1 and IL-6 blockers are some of the main therapeutic options used for treating secondary amyloidosis (AA). In the case of renal failure due to this type, acute or chronic dialysis might be required.
Familial amyloidosis (ATTR)
Formerly referred to as senile systemic amyloidosis, it is an inherited form of the disease caused by a mutation in the transthyretin (TTR) gene. It produces an abnormal transthyretin gene, and the most common symptoms of this type are cardiomyopathy (enlarged heart muscles) and neuropathy (peripheral nervous system failure). The symptoms can manifest between 40 and 55 years of age. Also, there are more than 100 different mutations of familial amyloidosis, which makes it more difficult to treat the disease.
Treating familial amyloidosis (ATTR) : Like secondary amyloidosis, there are very few options available for treating this type. Some FDA-approved medicines are:
- ATTR stabilizers : These medicines are used to stabilize the abnormal ATTR protein that causes the disease by preventing it from breaking into amyloid fibrils.
- ATTR silencers : These medicines act on the liver, reducing the production of TTR. They have been specifically studied on patients with nerve problems.
- Fibril disruptors : This new form of medication helps break up and clear ATTR amyloid fibrils.
Since TTR is produced in the liver, a liver transplant is also a possible treatment in some forms of familial amyloidosis.
Localized amyloidosis (ALoc)
There are many forms of ALoc amyloidosis that leads to deposits in the airway (trachea or bronchus), urinary bladder, or the eyes. It is often caused by the formation of immunoglobin light chains, and these do not originate from the bone marrow. Other types of ALoc amyloidosis are associated with endocrine proteins that are produced in the skin, heart, and other parts of the body.
Treating ALoc amyloidosis : The best way to treat this type is to treat the underlying disease. This can be either through surgery, medications, or both. Apart from this, targeting the specific protein causing the disease can also slow down the progression of the disease.
It is necessary for the patient and their loved ones to be careful about the symptoms of the disease as the doctors will provide treatments based on the same. Supportive care like pain medications and counseling is also necessary to manage the disease.