The opinions contained within this commentary are solely those of Kena C. Miller, MSN, FNP, and are not supported or endorsed by MediCom Worldwide, Inc. or Millennium Pharmaceuticals, Inc. and its affiliates or Cephalon Oncology.
Now we are going to talk about renal impairment, especially with multiple myeloma. Over 30% of patients will develop renal insufficiency throughout their course of their disease; interestingly, a lot of patients actually present with renal insufficiency or even renal failure. This is part of the biology of the disease. The myeloma proteins are very large. Think about your kidneys, the kidneys are the filter of the body and all of these large proteins go through the filter. The way I explain this to patients, it is like pulp orange juice going through a strainer. If you keep a lot of fluids on board flushing the pulp through the strainer, your kidneys will work well. Another way I describe this to patients is I have never met a myeloma that I trust yet. So you need to always be diligent in monitoring your patients’ kidney function. What you are looking for on your lab values is your serum creatinine, your BUN, and you look for your calcium levels as well, as hypercalcemia can also be very damaging to the kidneys. Due to bone destruction that is also associated with multiple myeloma, the serum calcium may also be elevated and you need to be very diligent in monitoring this and controlling it as this will also contribute to renal damage for our myeloma patients.
What we need to do is always, always, counsel the patients. They need a very liberal fluid intake. I will typically tell a patient a liter and half to two liters of fluid a day. It does not matter what the fluid is, it can be any kind of fluid, coffee, tea, juice, any kind of fluid at all. Water is the best always because it does not need to be processed in any way, easy in and easy out. You need to avoid nephrotoxic drugs, examples of this would be NSAIDs, aminoglycosides, and antibiotics, and another issue that you have to be very diligent is counseling the patients that if they are not feeling well, if their chemotherapy is causing persistent nausea and vomiting and diarrhea and it is happening on a Thursday, do not wait until your clinic appointment on Monday because your kidneys may be compromised. I have seen this, unfortunately, with several patients that they do not want to bother you and they do not call you and then when they present they are often in renal failure because they were not able to take in fluids. You need to be very cautious if you need to do CAT scans with your patients as the dye is also nephrotoxic and can be very detrimental to patients’ kidneys. We always need to think about infection. Interestingly, because this is a clinical clientele that has a compromised immune system, they are very high risk for infection and sudden onset of infection will also damage the kidneys very severely and then if you end up with infection and then you add in antibiotics it becomes another issue.
You may also need to dose-adjust medications for your patients in renal insufficiency; an example would be such antiviral medicines such as acyclovir. If their kidneys are compromised, their creatinine and their creatinine clearance especially is diminished, you may need to dose-adjust your medications. Also, some of our chemotherapeutic agents you may need to dose/redose those. An example would be the IMiD lenalidomide, you need to dose adjust for renal impairment. Other medications such as bortezomib, you can use this in renal insufficiency and you can also use it in patients with renal failure. You just need to time it for when the patients have their hemodialysis.
We also need to consider for our multiple myeloma patients comorbidities, patients with diabetes will often have high casts levels and this will damage their kidneys as well. Uncontrolled hypertension is another issue that will cause renal damage. Patients, when they end up with a diagnosis of cancer, particularly multiple myeloma, they forget that you need to control all of your other comorbidities, become so focused on their cancer diagnosis that they forget about all the other comorbidities that will also influence how we can treat and how we can manage their multiple myeloma.
Dimopoulos MA, Terpos E, Chanan-Khan A, et al. Renal impairment in patients with multiple myeloma: a consensus statement on behalf of the International Myeloma Working Group. J Clin Oncol. 2010;28(33):4976-4984.
Dimopoulos MA, Kastritis E, Rosinol L, et al. Pathogenesis and treatment of renal failure in multiple myeloma. Leukemia. 2008;22(8):1485-1493.
ZOVIRAX® (acyclovir) Prescribing information. GlaxoSmithKline, Research Triangle Park, NC 27709. November 2007.
Reviewed on January 17, 2017 for clinical relevance.