Renal Salt-Wasting Syndrome in a Patient With Cisplatin-Induced Hyponatremia

Abstract

Hyponatremia after chemotherapy is not an uncommon clinical syndrome. Both renal salt-wasting syndrome (RSWS) and syndrome of inappropriate antidiuretic hormone secretion (SIADH) have been reported as the underlying mechanisms for chemotherapy-induced hyponatremia. However, these two clinical syndromes have distinct clinical characteristics and managements. The key differential diagnostic feature for RSWS is the excessive urinary excretion of sodium, whereas the urinary excretion of sodium in SIADH is normal or decreased. The treatment for RSWS is supplement of salt, which is opposite to the treatment of SIADH. We report a case of a patient with hyponatremia and excessive urinary excretion of sodium after cisplatin-based chemotherapy. RSWS was diagnosed and the patient was treated with a sodium supplement. We also summarize the key diagnostic features and the most common differential diagnoses for hyponatremia syndrome.

Diagnosis and management of hyponatremia in cancer patients

“…The chemotherapeutic agents vincristine, vinblastine, cyclophosphamide, cisplatin, and [33,39,47], and cisplatin diminishes renal function [9,14,18,32]. Nausea induced by chemotherapy, as well as radiotherapy to the abdominal area, promotes the release of AVP; vomiting is also a potent stimulus for AVP release and leads to gastrointestinal loss of sodium [16,27,41].…”

Renal Salt Wasting Syndrome due to Carboplatin in a Patient with Lung Cancer

“…From this perspective, the hyponatremia of the present case showed immediate correction via intravenous infusion of isotonic saline The elevated plasma renin, aldosterone, and ADH and low normal atrial natriuretic peptide levels are all physiologic consequences of RSWS. [2][3][4][5] However, the extent of Extracellular Volume (ECV) depletion in RSWS seems to depend on the severity of renal dysfunction of sodium reabsorption. Furthermore, physical assessment of ECV is limited, which leads to a therapeutic dilemma: to restrict water for SIADH or to administer isotonic saline in RSW, especially in mild RSWS with normal to slightly depleted ECV, as in the present case.…”

Small Cell Gallbladder Carcinoma Complicated by Paraneoplastic Hyponatremia: A Case Report and Literature Review

“…Furthermore, hyponatremia may also complicate treatment as it may be aggravated by certain types of chemotherapy, such as in our patient's case. Cisplatin therapy causes hyponatremia by renal salt wasting [7] and could mask the improvement in paraneoplastic hyponatremia caused by tumor shrinkage.…”