Amyloidosis occurs when amyloid – a protein produced in the bone marrow – builds up in organs and tissues, affecting their function.
Amyloidosis is a rare condition that occurs when the protein amyloid builds up in the heart, kidneys, liver, or other organs or tissues. Normally, amyloid is produced in the bone marrow and deposited into other tissues and organs. When too much amyloid builds up, it causes problems with the way the organs function. Severe amyloidosis can cause organ failure.
There are several types of amyloidosis, and depending on the type your child has, different organs and tissues may be affected. Types of amyloidosis include:
AL amyloidosis is the most common form of the condition and was previously called primary amyloidosis. AL amyloidosis happens when the bone marrow produces abnormal antibodies that cannot be broken down by your child’s body and therefore, interfere with normal function. This most often affects the heart, kidneys, skin, nerves and liver.
AA amyloidosis, previously known as secondary amyloidosis, AA amyloidosis usually affects the kidneys and can also affect the digestive tract, liver or heart. Children who have chronic infections or inflammatory diseases are at risk for AA amyloidosis.
Hereditary amyloidosis, also called familial amyloidosis, this type of amyloidosis happens when a child has an inherited gene defect. Hereditary amyloidosis most often affects the heart, kidneys, liver or nervous system.
Dialysis-related amyloidosis is associated with receiving long-term dialysis (process of removing waste and extra fluid from the body). As a result of dialysis, some proteins in the blood may be deposited in joints and tendons, causing amyloidosis.
In general, amyloidosis is caused by the buildup of an abnormal protein called amyloid. The specific cause of the condition can vary based on the type of amyloidosis your child has.
American Board of Pediatrics/Nephrology