Tuesday, April 23, 2013
Kidney failure in Multiple Myeloma
Multiple myeloma (MM) is a clonal B-cell disease of slowly proliferating plasma cells, accompanied by monoclonal protein production and lytic bone lesions. Up to 50 per cent of newly diagnosed patients have a decrease in creatine clearance and 20 per cent of Multiple Myeloma patients Kidney failure occurs as a consequence of elevated calcium levels in the blood or when the kidneys are overloaded with protein.
Normally, the kidneys remove wastes, extra fluids, and minerals from the blood. But when they stop functioning, harmful wastes build up and this can cause other complications such as high blood pressure. In addition, the disease can cause too much calcium to leave your bones and head into your bloodstream, where it can put a strain on your kidneys.
When kidney failure is irreversible, patients undergo a procedure known as dialysis to help their bodies filter blood. Dialysis removes the extra fluid and waste from the blood, and it can prolong the overall survival for multiple myeloma patients.
The incidence of renal failure certainly rises as the tumor load increases, but it is the underlying tumor burden that ultimately determines survival. Therefore, treatment of myeloma to achieve reduction might also reduce the occurrence of kidney failure.
The most common test used as a follow-up to abnormal routine tests and to help diagnose the disease include Protein and Immunofixation Electrophoresis. This test is used to diagnose and monitor multiple myeloma. Protein electrophoresis separates the proteins in a blood or urine sample into several groups based on their electrical charge and size. In most patients with multiple myeloma, large amounts of an abnormal immunoglobulin protein (M-protein) will show up as a large peak on the electrophoresis graph.
Usually, both a blood and a urine sample will be tested during the diagnosis of multiple myeloma because some proteins, such as the Bence Jones proteins (free light chains), may not show up in significant quantities in blood samples, while those with only intact immunoglobulins may not have the abnormal protein in urine.
Bence Jones protein (free light chains) can be detected in the urine of some patients with multiple myeloma. Cancer screening exams are important medical tests done when you’re at risk but don’t have symptoms. They help find cancer at its earliest stage, when the chances for successful treatment are best.
—Dr Bharat Vaswani, Yashoda Hospital