It is difficult to diagnose multiple myeloma early. Often, multiple myeloma causes no symptoms until it has reached an advanced stage. In some cases, it may cause vague symptoms that at first seem to be due to other diseases. Rarely, multiple myeloma is found early when a routine blood test shows an abnormally high amount of protein in the blood.

Signs and symptoms of multiple myeloma

Although some patients with multiple myeloma have no symptoms at all, the following are the most common symptoms of this disease:

Bone pain

Normally, the 2 major kinds of bone cells work together to keep bones healthy and strong. The cells that lay down new bone are called osteoblasts. The cells that break down old bone are called osteoclasts. Myeloma cells make a substance that tells the osteoclasts to speed up the dissolving of bone. The osteoblasts do not get a signal to put down new bone, so old bone is being broken down without new bone to replace it. This can cause areas of bone weakness that are painful. These changes increase the chance that the bones will break, even with minor stress or injury. Any bone may be affected, but pain in the bones in the back, the hips, and skull is particularly common.

Low blood counts

When myeloma cells replace the normal blood-forming marrow cells, shortages of red blood cells, white blood cells, and blood platelets result. A reduced number of red blood cells, a condition called anemia, causes weakness, reduced ability to exercise, shortness of breath, and dizziness. Too few white blood cells (a condition called leukopenia) lowers resistance to infections such as pneumonia. When blood platelet counts are low (a condition called thrombocytopenia), even minor scrapes, cuts, or bruises may cause serious bleeding.

High blood calcium

When the myeloma cells dissolve bone, calcium is released. This can lead to high blood levels of calcium (called hypercalcemia). Symptoms include feeling very thirsty, drinking a lot of fluids, and urinating (peeing) a lot. This can cause dehydration and even kidney failure. High calcium can also cause severe constipation and loss of appetite. It can make people feel weak, drowsy, and confused. If the level of calcium gets high enough, it can even cause you to lapse into a coma.

Nervous system symptoms

If myeloma causes the bones in the spine to become weak, they can collapses and press on spinal nerves. This can cause sudden severe pain, numbness, and/or muscle weakness. This is a medical emergency and your doctor must be notified as soon as possible.

Sometimes, the abnormal proteins produced by myeloma cells can be toxic to the nerves. This damage can lead to weakness and numbness.

In some patients, large amounts of myeloma protein can cause the blood to "thicken." This can slow blood flow to the brain and cause confusion, dizziness, and stroke-like symptoms. Patients with these symptoms should call their doctor. Removing the protein from the blood by a procedure called plasmapheresis can rapidly reverse this problem.

Kidney problems

Myeloma protein can damage the kidneys. Early on, this doesn't cause any symptoms, but can be found with a blood test. As the kidneys start to fail, they lose the ability to dispose of excess salt, fluid, and body waste products. This can lead to symptoms like weakness and leg swelling.

Infections

Myeloma patients are about 15 times more likely to get infections. This happens because the body is unable to make the antibodies that help fight infection. Often, once someone with myeloma gets an infection, it is slow to respond to treatment. That person may stay sick for a long time. Pneumonia is a common and serious infection seen in myeloma patients.

Last Medical Review: 02/13/2009
Last Revised: 05/12/2009