2019 Research Forum

Presenter: Simmer Kaur MD R2 Principal Investigator & Faculty Sponsor: Arash Heidari MD

Acute Tubular Dysfunction with Lower Doses of Cisplatin

Simmer Kaur MD R2, Sabitha Eppanapally MD, Arash Heidari MD

INTRODUCTION Cisplatin is a cancer chemotherapeutic agent widely used for the treatment of many solid-organ cancers. However, its clinical use is complicated by its dose-related renal injury. Nephrotoxicity due to cisplatin is manifested as progressive renal impairment, salt-wasting, a Fanconi-like syndrome, hypomagnesemia. One study suggested that decrease in GFR and magnesium concentration happen after doses higher than 50 mg/m2 body surface area per dose. Another study reported renal damage occurs when approximately 500 mg of cumulative drug had been administered. DISCUSSION 63-year old Caucasian female with stage IIIc endometrial carcinoma completed 9 cycles of 40mg/m2/week cisplatin chemotherapy with radiation presented to the emergency department with intractable nausea and vomiting which started after completing her 7th cycle of cisplatin. On presentation, her vitals were stable, physical examwas remarkable for orthostatic hypotension and a resting tremor in both upper extremities. Her labs where significant for potassium of 2.5, chloride of 89, bicarbonate 33, creatinine of 0.74, magnesium levels < 0.3 and calcium of 5.4. She received fluids and electrolyte replacement. However, this patient continued to have low level of serum magnesium, potassium, phosphorus and calcium despite adequate IV replacements which indicate losses in the urine. Her 24-hour urine electrolytes and amino acid analysis showed increase excretion of magnesium, potassium, sodium and elevated levels of multiple amino acids. Once her nausea was controlled she was switched to oral supplementation of magnesium, potassium, and calcium. Daily serum levels of potassium, phosphorous and calcium were stable. However, magnesium levels continued to be low. This patient was clinically stable and was subsequently discharged home with a plan for daily IV infusions of magnesium at an infusion center with close monitoring of serum electrolytes. CONCLUSION Long-term effects of cisplatin toxicity may lead to subclinical and/or permanent reduction in GFR. Clinician should monitor renal functions closely as tubular dysfunction can occur after only a dose of 360 mg and hypomagnesemia can occur after only 120 mg of cumulative drug is administered.

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