13 NCCN Guidelines for Patients ® : Multiple Myeloma, 2019 1 Multiple myeloma Review Bruising or bleeding easily Platelets are blood cells that help heal wounds and stop bleeding. They do this by forming blood clots. Bruising or bleeding easily is a symptom of having a low number of platelets. Too many myeloma cells in the bone marrow can crowd out the cells that make platelets. Frequent infections and fevers Fever is a sign that your body is trying to fight off an infection. Frequent fevers and infections are symptoms of having too few white blood cells, but this can also be due to low levels of normal antibodies. A low number of white blood cells can result from too many myeloma cells in the bone marrow. Bone damage and pain Myeloma cells can cause bone damage when they crowd out normal cells in the bone marrow. They also release chemicals that begin to break down bone. Areas of bone damage are called bone lesions and can be very painful. Bone lesions also weaken bones so they may break (fracture) easily. Common sites of bone damage from myeloma are the spine, skull, hip bone, ribs, arms, and collarbone. See Figure 5. The most common fracture site is in the bones (vertebrae) of the spine. Fractures of the vertebrae can be very painful, but they can also occur without any pain. Kidney problems The kidneys are a pair of organs that filter blood to remove waste, which leaves the body in urine. Increased or decreased urine output is a symptom of kidney damage. The high levels of M-proteins made by the myeloma cells can cause kidney damage. Myeloma can damage bones, and this bone damage causes calcium to be released into the bloodstream. Calcium is a mineral needed for healthy bones. But, high levels of calcium in the bloodstream can damage the kidneys and cause other symptoms. Review Myeloma is a cancer of plasma cells. Plasma cells make antibodies that help to fight infections and play a key role in bone repair. Myeloma cells make too many copies of themselves. Myeloma cells make abnormal antibodies called M-proteins that don’t help to fight germs. One mass of myeloma cells is called a solitary plasmacytoma. When myeloma cells have spread throughout the bone marrow, it is called multiple myeloma. Smoldering (asymptomatic) myeloma doesn’t cause symptoms. Active (symptomatic) myeloma causes symptoms by taking over bone marrow and may cause high blood calcium, kidney damage, or anemia, or may destroy bone.