What is Multicentric Castleman’s Disease?
Multicentric Castleman’s Disease (MCD) is a rare illness that affects the lymph nodes and related tissues.
The lymph system is a major part of the body’s immune system that helps fight off infection.
The lymph system is made up of:
- Lymph—a clear-to-white fluid that contains white blood cells, especially lymphocytes, which attack bacteria in the blood
- Lymph vessels—tubes through which the lymph is able to flow throughout the body
- Lymph nodes—glands found along the lymph vessels throughout the body
Our bodies have a network of lymph nodes and lymph vessels that collect and carry watery, clear lymph fluid, much like veins collect and carry blood from distant parts of the body (like the arms and legs) and carry it back to the heart. Lymph fluid has proteins, salts, and water, as well as white blood cells, which help fight infections. In the lymph vessels, one-way valves work with body muscles to help move the fluid through the body.
With Multicentric Castleman’s Disease, too many cells grow in the lymph nodes. This causes the lymph nodes to become enlarged. That makes it a lymphoproliferative disorder.A number of lymphoproliferative disorders exist, including lymphoma, which is cancer of the lymph system. Though MCD is not a cancer, having MCD may make some people more likely than others to develop lymphoma.
Though the cause of MCD is not fully understood, it is believed that a protein in the body called interleukin-6 (IL-6) has a role in the disease.
When produced in the normal amounts, IL-6 helps regulate the activity of the immune system. Often, high levels of IL-6 are seen in patients with MCD. As a result, white blood cells called lymphocytes multiply too rapidly. This causes the lymph nodes to become enlarged, and other symptoms may occur.
Multicentric Castleman’s Disease (MCD) symptoms may include:
- Weakness and tiredness (fatigue)
- Night sweats (that soak the sheets)
- Unintentional weight loss
- Loss of appetite
- Nausea and vomiting
- Numbness and tingling (neuropathy)
- Leg swelling (edema)
- Skin rashes
The symptoms of MCD usually come on gradually. For some patients, however, the symptoms seem to begin after they have had some sort of viral infection.
Many Multicentric Castleman’s Disease (MCD) symptoms are similar to those of other diseases such as infections and lymphoma. And because Multicentric Castleman’s Disease is rare, healthcare professionals often suspect other diseases first. This can make diagnosing MCD slow and frustrating for both patients and healthcare professionals.
Diagnosing Multicentric Castleman’s Disease often includes some or all of the following processes:
- A physical examination and detailed patient history.
- Blood and urine tests, which may help the healthcare professional rule out other infections or diseases. They may also show anemia or elevated levels of interleukin-6 (IL-6) a protein that is produced by cells in the lymph nodes.
- Imaging tests, such as computed tomography (CT) scan, magnetic resonance imaging (MRI), or ultrasound, which may show enlarged lymph nodes or organs.
ROLE OF IL-6
Multicentric Castleman’s Disease (MCD) has been linked to a protein called interleukin-6 (IL-6).
Normally, IL-6, which is produced by cells within the lymph nodes (plasma cells), helps our bodies regulate our immune system. But when we produce too much of it, lymphocytes, which are the main cells of the immune system, grow and divide too quickly. This can cause lymph nodes to become enlarged. It can also cause inflammation throughout the body, and autoimmune reactions.
IL-6 has been associated with a number of diseases, including cancer and autoimmune conditions, but the relationship between IL-6 and MCD appears to be strong. The central role that IL-6 plays in MCD is shown by the fact that symptoms tend to increase or decrease depending on the amount of IL-6 in a person’s system.