Plasma cell dyscrasia

Overview

Plasma cell dyscrasia often refers to a group of blood conditions called plasma cell disorders. It's not one specific health condition. It's a phrase that describes changes in white blood cells called plasma cells. The cells may not grow as expected, or there may be more of them than usual. Plasma cell dyscrasia and plasma cell disorder are sometimes used to mean the same thing.

Plasma cells are part of the body's immune system. Healthy plasma cells make proteins called antibodies that help the body fight infections. But in plasma cell dyscrasia, the plasma cells make identical copies of themselves. The group of identical copies are called a clone. A clone may make a lot of one type of antibody called a monoclonal protein (M protein), also called a paraprotein. As the body makes more M protein, the number of antibodies that fight infection can go down.

Plasma cell dyscrasia includes conditions that are cancer and not cancer. An example of a plasma cell dyscrasia that is cancer is multiple myeloma. Monoclonal gammopathy of undetermined significance (MGUS) is an example of a plasma cell dyscrasia that is not cancer.

Types

Types of plasma cell dyscrasia include:

• Monoclonal gammopathy of undetermined significance (MGUS). In this type, there is a monoclonal protein (M protein) in the blood. There is no organ damage, and it's not cancer. But having MGUS raises the risk of getting cancer of the plasma cells and related conditions. Most people with MGUS do not develop plasma cell cancer or related conditions.
• Plasmacytoma. This cancer of the plasma cells usually forms in the bone or in soft tissue.
• Multiple myeloma. This is a blood cancer that develops from changed plasma cells. If blood or bone marrow tests show this plasma cell condition, but there are no signs of active disease, such as organ damage or bone lesions, the condition is called smoldering multiple myeloma.
• AL amyloidosis. In this rare type of plasma cell dyscrasia, a substance called amyloid builds up in the body. The amyloid forms when proteins fold the wrong way and stick together. Amyloid buildup can damage organs and tissues.
• POEMS syndrome. This is a rare type of plasma cell dyscrasia. The condition can affect many parts of the body, including the nerves. The term POEMS stands for polyneuropathy, organomegaly, endocrinopathy, monoclonal plasma cell disorder and skin changes.
• Waldenstrom macroglobulinemia. This is a rare cancer of the white blood cells. The condition also is called lymphoplasmacytic lymphoma.

A rare condition called Castleman disease also can affect some immune cells, including plasma cells. Lymph nodes and other lymph tissues are affected too. But Castleman disease is generally considered a lymphoproliferative disorder, not a plasma cell dyscrasia.

Symptoms

Symptoms depend on the type of plasma cell dyscrasia and the part of the body affected. Each condition has its own unique symptoms. For example:

• Multiple myeloma symptoms may include bone pain, backaches, frequent infections and kidney trouble. If the condition causes a low number of red blood cells, called anemia, you may feel very tired.
• AL amyloidosis symptoms depend on the organ affected. If it affects the heart, you may feel short of breath or faint. If it affects your kidneys, you may have foamy or frothy urine. Nerve involvement may cause numbness, tingling, pain or weakness.
• POEMS syndrome symptoms may include numbness, tingling, pain or weakness. It also can cause skin color changes and make organs larger than usual.
• Waldenstrom macroglobulinemia may make you feel very tired or weak. Other symptoms may include bleeding, numbness and tingling.
• Plasmacytoma symptoms depend on where the tumor is. The condition may cause bone pain.

These are not all of the possible symptoms of plasma cell dyscrasia. Some types, such as monoclonal gammopathy of undetermined significance (MGUS) and smoldering myeloma, may not cause symptoms. Tell your healthcare team about any symptoms you have. Your care team can do tests to find the cause of your symptoms.

When to seek care

Make an appointment for a health checkup if you have symptoms of a plasma cell dyscrasia such as:

• Bone pain that continues or is not explained.
• Shortness of breath.
• Irregular heartbeats.
• Numbness or tingling.
• Tiredness that is not typical.

Also tell your healthcare professional if you have an infection that lasts longer than expected or keeps coming back.

These symptoms can have many causes. They do not always mean you have a plasma cell disorder. A healthcare professional can do tests to learn the cause.

When to seek emergency care

Get emergency medical help if you have:

• Sudden or severe shortness of breath.
• Chest pain.
• Fainting.
• Confusion.

Also get emergency care if you have severe back pain that happens with:

• Weakness or numbness in the legs that is new.
• Trouble walking.
• Loss of bladder or bowel control.

Causes

The exact cause of plasma cell dyscrasia is not known.

Plasma cell dyscrasia happens when white blood cells called plasma cells change and make copies of themselves. This forms a group of identical cells called a clone. The clone may make large amounts of the same protein or protein part, such as monoclonal protein (M protein) or light chains. Over time, the plasma cells or the proteins they make may build up in the body. How these changes affect the body depends on the type of plasma cell dyscrasia.

Risk factors

The risk factors for a plasma cell dyscrasia depend on the type. In general, risk factors may include:

• Age. Growing older raises the risk of some types of plasma cell dyscrasia. For example, multiple myeloma and Waldenstrom macroglobulinemia often are diagnosed around the mid-60s.
• Race. Monoclonal gammopathy of undetermined significance (MGUS) and multiple myeloma are more common in Black people. Waldenstrom macroglobulinemia is diagnosed more often in white people.
• Sex at birth. Some types of plasma cell dyscrasia are more common in men, including multiple myeloma, AL amyloidosis and Waldenstrom macroglobulinemia.
• Family history. Having a close family member with MGUS, multiple myeloma or Waldenstrom macroglobulinemia may raise your risk of one of these conditions.
• Other plasma cell disorders. For example, MGUS can sometimes lead to multiple myeloma, AL amyloidosis or a related blood cancer, including Waldenstrom macroglobulinemia. But most people with MGUS do not develop a related cancer. In some people, smoldering multiple myeloma may turn into active multiple myeloma.

Complications

Complications of plasma cell dyscrasia depend on the type. Some types do not cause complications. Others may affect different parts of the body. Complications may include:

• Blood clots or blood that becomes too thick.
• Damage to the bones, heart, kidneys or nerves.
• High levels of calcium in the blood, called hypercalcemia, which can cause weakness or confusion.
• Infections that happen often, especially pneumonia and kidney infections.
• Low red blood cell levels, called anemia.

This is not a complete list of possible complications. Talk with your healthcare team to learn what complications may be possible for your type of plasma cell dyscrasia.