Plasma cells refer to cells that produce antibodies (immunoglobulins), proteins that are necessary to defend the body against infection. According to the Merck Manual, a compilation of medical information for medical professionals, plasma cells are derived from B lymphocytes, another type of immune cell that protects the body. Sometimes, the plasma cells can multiply uncontrollably and lead to plasma cell diseases.
Multiple Myeloma
Multiple myeloma refers to a cancer of the plasma cells, the Mayo Clinic says. Symptoms of multiple myeloma include bone pain in the pelvis, back, skull and ribs. It can also lead to high levels of calcium in the blood and abnormal proteins in the urine or blood. Other symptoms of multiple myeloma include constipation, nausea, confusion, a poor appetite, excessive thirst, weight loss and numbness or weakness in the legs. Multiple myeloma also includes bone fractures, repeated fractures and anemia.
The exact cause of multiple myeloma is unknown, but it begins when a plasma cell becomes abnormal.
No cure exists for multiple myeloma, but treatment for multiple myeloma includes taking such medications as bortezomib, thalidomide, corticosteroids and lenalidomide. Chemotherapy, radiation and stem cell transplantation are other treatments available for multiple myeloma.
Monoclonal Gammopathy of Undetermined Significance
Monoclonal gammopathy of undetermined significance (MGUS) is a condition in which abnormal protein levels develop. These particular proteins develop from plasma cells. The Mayo Clinic says that abnormal proteins develop in 1 percent of healthy people greater than 50 years old and greater than 3 percent of people over age 70.
Typically, MGUS is discovered through blood tests.
Typically, no treatment is necessary for MGUS. Physicians will monitor the blood regularly to check the levels of the abnormal protein.
Heavy Chain Diseases
Heavy chain disease refers to a malignant disease in which excessive amounts of heavy chain antibodies ( a type of protein that fights infection) are produced from plasma cells. There are a few types of heavy chain diseases.
IgA heavy chain disease is the most common of all the heavy chain diseases, the Merck Manual says. IgA disease typically appears in people living in the Middle East who are between the ages of 10 and 30. People with this disease complain of stomach bloating, indigestion, heartburn and diarrhea. Merck says that the cause may be due to an abnormal response to a foreign invader such as a parasite. Treatment involves taking corticosteroids, cytotoxic drugs and broad-spectrum antibiotics. The disease presents differently in each person. Some IgA heavy chain disease sufferers die within one to two years.
IgG heavy chain disease usually occurs in elderly men or children, the Merck Manual says. Typically, this disease is associated with other diseases like Sjogren's syndrome (a condition of dry eyes and dry mouth) and tuberculosis. Symptoms include a large spleen, fever and infections. Medications such as vincristine and corticosteroids and radiation may lead to symptom-free periods, but people typically die within one year.
IgM heavy chain disease is found in adults more than 50 years old. Fractures and lymph node swelling are just some of the symptoms of this disease. Medications called alkylating agents and corticosteroids can be used to induce symptom-free periods.
