Kidney failure, the inability of the kidneys to properly expel waste from the body, is a common side effect of multiple myeloma. Approximately 20 percent of all myeloma patients develop progressive kidney failure sometime during the course of their disease.

The signs and symptoms of kidney failure that often occur in myeloma patients include hypercalcemia and excess free light chains in the blood.

Hypercalcemia is a disorder that occurs when a myeloma patient’s affected or damaged bone dissolves and creates an overabundance of calcium in the bloodstream. The kidneys overwork while processing the extra calcium, which may cause permanent damage.

Alternatively, kidney failure may happen if kidney tubules are damaged by the excretion of free light chains – overproduced molecules that are often present in the blood of myeloma patients.

Other factors may contribute to kidney failure as well, such as dehydration and the intake of non-steroidal, anti-inflammatory drugs – such as aspirin or ibuprofen – that reduce blood flow to the kidneys.

Kidney failure in myeloma patients may be either chronic (reoccurring), or acute, meaning that symptoms are short-lived yet severe.

Signs of kidney failure may be seen at myeloma diagnosis. Up to 50 percent of newly diagnosed patients experience a decrease in creatine clearance, which indicates improper kidney function. Creatine is a compound found in the body’s muscles. It is routinely removed from the blood by the kidneys, but when the kidneys are not functioning properly, creatine cannot be easily removed.

In addition, approximately nine percent of newly diagnosed myeloma patients require dialysis treatment due to severe kidney failure. Dialysis removes excess water and waste products from the blood when kidneys fail.

Myeloma patients experiencing kidney failure are often excluded from aggressive or high-dose chemotherapy treatments. This is because failing kidneys cannot quickly expel the treatment’s chemicals from the body, creating a toxic build-up in the blood that can become dangerous.

The majority of affected myeloma patients recover, to some degree, from kidney failure. Half of those who improve will do so within six weeks of the condition’s onset. The recovery occurs due to rehydration, the correction of hypercalcemia, or the discontinuance of drugs that reduce kidney blood flow.

Currently, researchers are examining the possibility of blood plasma exchange to remove light chains from the blood, which would further reduce the occurrence of kidney failure.

Other novel treatments, such as a combined Velcade (bortezomib), doxorubicin (Adrianmycin), and dexamethasone (Decadron) regimen, are also being tested for usefulness in reversing light chain-induced kidney failure.

Though not all patients recover from kidney failure, most patients will only be left with mild to moderate kidney impairment, and only less than one percent will require long-term kidney replacement treatment.

For more information on the novel combined Velcade-Doxorubicin-dexamethasone treatment, visit the International Myeloma Foundation’s website for study results. Also, for more information on kidney failure in multiple myeloma patients, please see the other Beacon articles in this series and related Beacon news articles.