Published: 18 Jun 2025

ICD9: 277.39      ICD10: E85.8      ICD11: 5D00

Amyloidosis is not a single disease, but rather a group of diseases where abnormal proteins, called amyloid, build up in your tissues and organs.
These amyloid deposits can interfere with the normal function of those organs. Think of it like sticky goo clogging up the gears of a machine.

Here's a breakdown of key aspects:

Amyloid: This is a general term for a misfolded protein that aggregates (clumps together) into insoluble fibrils. These fibrils deposit in tissues and organs. The *type* of amyloid protein deposited determines the type of amyloidosis.

Mechanism: Normally, proteins fold into specific shapes to carry out their functions. In amyloidosis, proteins misfold and become resistant to breakdown. These misfolded proteins then stick together, forming amyloid fibrils.

Organ Involvement: Amyloid deposits can affect virtually any organ in the body. Commonly affected organs include the heart, kidneys, liver, spleen, nervous system, and digestive tract.

Symptoms: Symptoms vary widely depending on which organs are affected. Some common symptoms can include:
Fatigue and weakness
Shortness of breath
Swelling of the ankles and legs
Numbness, tingling, or pain in the hands and feet
Unexplained weight loss
Skin changes (e.g., bruising easily, waxy skin)
Diarrhea or constipation

Types of Amyloidosis: There are several types of amyloidosis, classified by the type of protein that forms the amyloid deposits. The most common types include:

AL Amyloidosis (Light Chain Amyloidosis): This is the most common type. It's associated with a plasma cell disorder where the bone marrow produces abnormal light chains (parts of antibodies) that misfold and form amyloid. It often affects the heart, kidneys, liver, and nerves.

AA Amyloidosis (Reactive Systemic Amyloidosis): This is caused by chronic inflammation from conditions like rheumatoid arthritis, inflammatory bowel disease, or chronic infections. The amyloid protein is derived from serum amyloid A (SAA), a protein produced by the liver during inflammation.

ATTR Amyloidosis (Transthyretin Amyloidosis): This type is caused by mutations in the *TTR* gene, which produces the transthyretin protein. Transthyretin carries thyroid hormone and vitamin A in the blood. There are two main forms:
Hereditary ATTR Amyloidosis (hATTR): Caused by inherited *TTR* gene mutations. Affects the nerves (causing neuropathy), heart, and other organs. Also called familial amyloid polyneuropathy (FAP) or familial amyloid cardiomyopathy (FAC).
Wild-Type ATTR Amyloidosis (wtATTR): Also called senile systemic amyloidosis (SSA). Occurs when the normal transthyretin protein becomes unstable and forms amyloid deposits, primarily affecting the heart. More common in older men.

Localized Amyloidosis: Amyloid deposits occur in a single organ or tissue, such as the skin, bladder, or larynx. Often less serious than systemic forms.

Diagnosis: Diagnosis typically involves a tissue biopsy to confirm the presence of amyloid deposits and to identify the type of amyloid protein. Other tests, such as blood tests, urine tests, and imaging studies (e.g., echocardiogram, MRI), are used to assess organ involvement.

Treatment: Treatment depends on the type of amyloidosis, the organs affected, and the severity of the condition. The goals of treatment are to slow the progression of the disease, manage symptoms, and improve the patient's quality of life. Treatment options can include:
Chemotherapy (for AL amyloidosis)
Anti-inflammatory medications (for AA amyloidosis)
TTR stabilizers or gene silencers (for ATTR amyloidosis)
Organ transplantation (e.g., heart or liver transplant)
Supportive care to manage symptoms

In summary, amyloidosis is a complex group of diseases characterized by the buildup of abnormal protein deposits in the body's tissues and organs. The specific type of amyloid protein determines the type of amyloidosis, which in turn influences the organs affected, the symptoms, and the treatment approach.

It's important to see a doctor if you experience symptoms that could be related to amyloidosis. Early diagnosis and treatment can help improve outcomes.