Amyloidosis – Find a Specialist and Get Information

Light-chain (AL) amyloidosis results from a disease of the bone marrow.

This leads to an overproduction of plasma cells, which are responsible for producing antibodies. In addition to intact antibodies, structurally altered free light chains also enter the bloodstream.

The body then deposits these in organ tissues. The proliferation of plasma cells is often due to a tumor of the lymphoid tissue.

AL amyloidosis therefore occurs particularly frequently in multiple myeloma or Waldenström’s macroglobulinemia. Both of these are malignant blood disorders.

AA amyloidosis, on the other hand, is caused by chronic inflammatory diseases. The trigger here is the acute-phase protein, which the body produces during chronic infections such as tuberculosis or leprosy.

Chronic inflammatory bowel diseases such as Crohn’s disease or ulcerative colitis, as well as rheumatic diseases, can also trigger AA amyloidosis.

Genetic changes and mutations can cause hereditary or familial amyloidosis. This condition frequently occurs in combination with other inherited diseases, such as familial Mediterranean fever.

The symptoms of the disease vary depending on which organ the protein strands are deposited in. If this occurs in the heart muscle, it leads to stiffening of the organ and, consequently, to a reduced blood supply to the body.

This type of cardiomyopathy manifests with symptoms such as:

• Heart rhythm disturbances
• Fainting spells
• Painful chest tightness (angina pectoris)
• Heart fluttering

The protein strands can also accumulate in the kidneys, leading to functional impairment there. The result is nephrotic syndrome, in which the kidneys lose protein.

This leads to fluid retention in the body. When immunoglobulins—which are responsible for the body’s immune defense—are lost, the patient becomes more susceptible to infections.

Amyloidosis of the gastrointestinal tract manifests primarily as diarrhea, bleeding, or intestinal obstructions accompanied by severe pain. The liver is enlarged and feels rock-hard on palpation.

The brain and nerves can also be affected by the disease. This leads to various functional disorders whose effects resemble those of dementia.

The protein strands can also cause damage to the peripheral nerves (nerves located outside the spinal cord and brain). Typical symptoms here include sensory and motor disturbances.

Carpal tunnel syndrome, along with nodular changes in the skin, hair loss, reddened circles around the eyes, or hoarseness, tends to indicate involvement of the soft tissues.

In rare cases, amyloidosis causes disturbances in the endocrine system, which manifest as thyroid disorders or adrenal insufficiency.

The symptoms of amyloidosis are often nonspecific and can also occur in other diseases. For this reason, the diagnosis is often not made until the disease has reached an advanced stage.

However, amyloidosis should always be suspected when a patient experiences the following symptoms:

• Cardiomyopathy
• Neurological dysfunction or
• Enlarged liver of unknown cause

Similarly, amyloidosis should always be considered as a possible comorbid condition in patients with multiple myeloma.

To make a definitive diagnosis, the doctor must take a tissue sample from an affected organ and have it examined in the laboratory. This reveals the exact composition of the protein fibers, which must be known for successful treatment.

In cases of generalized amyloidosis, the sample can also be gently extracted from the subcutaneous fat tissue. Once amyloidosis has been confirmed through these diagnostic procedures, doctors perform a bone marrow aspiration to identify underlying causes.

Doctors assess the extent of the fibril deposits using scintigraphy. In this procedure, patients are administered radioactively labeled substances that bind to the protein fibrils. These are visible using imaging techniques.

However, diagnosis is often difficult. In most cases, it is not confirmed until after death during an autopsy.

The majority of amyloidosis cases are treatable today. Treatment depends on the form of the disease. For example, the uncontrolled proliferation of plasma cells can usually be curbed through high-dose chemotherapy followed by a stem cell transplant.

In people with AL amyloidosis, chemotherapy can halt the disease in the bone marrow and prevent further amyloid deposits @ Rido /AdobeStock

Patients with Mediterranean fever can counteract the development of amyloidosis by taking the drug colchicine.

Doctors treat organ damage using various general measures and medications.

People with heart disease are prescribed ACE inhibitors and diuretics to lower blood pressure. If the kidneys are affected, a low-sodium diet may be beneficial.

Whether and how effectively amyloidosis can be treated depends on the form of the disease and the patient’s age.

The presence of multiple myeloma or heart disease significantly worsens the prognosis.

Mild forms, on the other hand, are often associated only with a slightly reduced life expectancy.