Multiple myeloma is a cancer in the bone marrow of the plasma cells--white blood cells that normally fight infection. The disease causes excessive production of these cells, leading to several complications. The complications vary among patients, depending on the sites of the cancer and the buildup of its abnormal proteins in the blood and urine.
Repeated Infections
Because the dysfunctional myeloma cells interfere with normal immune function, people with multiple myeloma have a high risk for frequent infections and fever. Respiratory tract infections include sinusitis and pneumonia. Patients may develop skin infections or shingles. Bladder and kidney infections occur frequently as well.
Bone Fractures
As myeloma cells increase, they erode bone mass. This causes bone pain and fractures, making it difficult for people with this disease to perform normal activities. If the vertebra are affected, the spinal cord may become compressed. This is a medical emergency, requiring immediate intervention to prevent paralysis. According to the Mayo Clinic, signs of spinal cord compression include weakness, or even paralysis, of the legs. Another indicator is severe back pain.
Kidney Problems
Kidney function is impaired in people with multiple myeloma, leading, in some cases, to kidney failure requiring dialysis. Up to one half of people with this cancer develop at least moderate kidney insufficiency, reports the "Cecil Textbook of Medicine." Eroding bones release excess calcium into the blood, thus interfering with kidney's ability to filter the blood's waste. Bence-Jones proteins, tiny pieces of myeloma-related antibodies, migrate into the kidneys' collecting system, sometimes causing permanent damage. Overgrowth of myeloma cancer cells produces uric acid in the urine, causing kidney stones.
Anemia
Excessive plasma cells prevent normal red blood cells from developing, causing anemia and other blood problems. Because the blood's oxygen-carrying capacity is impaired, patients feel weak and very tired. They may look pale. According to the Merck Manual, in multiple myeloma, heart problems are an extreme effect of reduced red blood cell production.
Hypercalcemia
Hypercalcemia, excess calcium in the blood, causes many nonspecific problems in people with multiple myeloma, including nausea, thirst, appetite loss, restlessness and confusion. Constipation and frequent urination also occur. Up to 20 percent of patients experience these complications, according to the "Cecil Textbook of Medicine." If left untreated, hypercalcemia leads to kidney damage.
Hyperviscosity Syndrome
In a few people with multiple myeloma, the excess of abnormal proteins thickens the blood, interfering with normal blood flow to the skin, extremities, kidneys and brain, reports the Merck Manual. In rare cases, because the heart must work harder to pump this thick, viscous blood, heart failure occurs. According to the "Cecil Textbook of Medicine," bleeding from the nose or mouth and blurred vision also signify hyperviscosity.
References
- MayoClinic.com: Multiple Myeloma
- The Patient Education Institute: X-Plain Multiple Myeloma. Reference Summary
- The Merck Manual: Multiple Myeloma
- Kyle RA: Plasma Cell Disorders in Cecil Textbook of Medicine.
