Amyloidosis

What is Amyloidosis?

• Amyloidosis is a rare disease that occurs when an abnormal protein, called amyloid, builds up in one’s organs, affecting their shape and functioning. 
• Amyloid deposits can build up in the heart, brain, kidneys, spleen and other parts of the body, leading to life-threatening conditions like organ failure.
• Amyloid isn’t normally found in the body, but can be formed from several different types of proteins. Some varieties of amyloidosis occur in association with other diseases. 
• These types may improve with treatment of the underlying disease. Some varieties of amyloidosis may lead to life-threatening organ failure.
• Amyloidosis may be secondary to a different health condition or can develop as a primary condition as well. 
• Sometimes, it is due to a mutation in a gene, but usually, the cause of amyloidosis remains unknown.
• Many different proteins can lead to amyloid deposits, but only a few lead to major health problems. 
• The type of protein and where it collects tell the type of amyloidosis one has. Amyloid deposits may collect throughout one’s body or in just one area.
• Moreover, while some varieties are hereditary, others are caused by outside factors, such as inflammatory diseases or long-term dialysis.
• Symptoms of amyloidosis are often subtle and can vary greatly depending on where the amyloid protein is collecting in the body. 
• As amyloidosis progresses, the deposits of amyloid can harm the heart, liver, spleen, kidneys, digestive tract, brain or nerves.

The general signs or symptoms would include:

• Severe fatigue.
• Loss of weight.
• Swelling in the belly, legs, ankles or feet.
• Numbness, pain or tingling in hands or feet.
• Changes in skin colour.
• Purple spots (purpura) or bruised-looking areas of skin around the eyes.
• Bleeding more than usual after an injury.
• Swelling of the tongue.
• Shortness of breath.

There are also different amyloidosis that are prevalent:

Light-chain (AL) amyloidosis- 

• It is the most common type in developed countries which can affect the kidneys, spleen, heart, and other organs. 
• People with conditions such as multiple myeloma or a bone marrow illness are more likely to have AL amyloidosis.
• This starts in plasma cells within the bone marrow. Plasma cells create antibodies with both heavy chain and light chain proteins. 
• If the plasma cells undergo abnormal changes, they produce excess light chain proteins that can end up in the bloodstream. 
• These damaged protein bits can accumulate in the body’s tissues and damage vital organs such as the heart.

AA amyloidosis-

• Previously known as secondary amyloidosis, this condition is the result of another chronic infectious or inflammatory disease, such as rheumatoid arthritis, Crohn’s disease, or ulcerative colitis. It mostly affects one’s kidneys, digestive tract, liver, and heart. 
• AA refers to the amyloid type A protein that causes it.

Dialysis-related amyloidosis-

• It is more common in older adults and people who have been on dialysis for more than 5 years. 
• This form of amyloidosis is caused by deposits of beta-2 microglobulin that build up in the blood. 
• Deposits can build up in many different tissues, but it most commonly affects bones, joints, and tendons.

Transthyretin amyloidosis–

• It can be inherited from a family member and is hence commonly referred to as familial amyloidosis. Transthyretin is a protein that is also known as prealbumin made in the liver. 
• As such, this often affects the liver, nerves, heart, and kidneys and many genetic defects are linked to a higher chance of amyloid disease.