Cisplatin-Induced Renal Salt Wasting in a Patient With Mediastinal Nonseminomatous Germ Cell Tumor

Cisplatin is a platinum-based, effective chemotherapy agent that is limited by nephrotoxicity. Hyponatremia is a common concern and both renal salt wasting (RSW) and SIADH can occur. The challenge lies in the diagnostic differentiation of RSW and SIADH, since the treatment of the two conditions differs. We present a 25-year-old man with a mediastinal nonseminomatous germ cell tumor undergoing VIP chemotherapy (etoposide, cisplatin, and ifosfamide), who developed polyuria and electrolyte imbalances indicative of RSW and Fanconi-like syndrome. This case underscores the importance of early diagnosis and tailored management of cisplatin-induced RSW to prevent severe renal impairment.