Ifosfamide-induced Fanconi syndrome with diabetes insipidus
A 61-year-old Russian man was admitted to the clinic for evaluation of a 5-cm axillary mass that had invaded the adjacent bony structures. He was diagnosed with inflammatory malignant fibrous histiocytoma. Neoadjuvant chemotherapy with adriamycin (25 mg/m2) and ifosfamide (2.5 g/m2) was administered on days 1 to 3 following mesna prophylaxis. On day 3 of chemotherapy, the patient showed general weakness, polyuria, and dehydration. Laboratory findings included hypernatremia (serum sodium, 150 mmol/L), hypokalemia (serum potassium, 1.7 mmol/L), hypercalcemia (serum calcium, 10.6 mg/dL), and hypophosphatemia (serum phosphate, 2.1 mg/dL). The combination of hypernatremia, hyperosmolarity, polydipsia, and polyuria were consistent with nephrogenic diabetes insipidus (). The patient was thus treated with electrolyte replacement and dichlozid. However, his electrolyte imbalances were aggravated by this treatment, and his mental status deteriorated to a stupor. Six days after chemotherapy, his serum blood urea nitrogen and creatinine levels increased to 49.5 mg/dL (normal, 5.0 to 25.0) and 1.81 mg/dL (normal, 0.5 to 1.4), respectively. A 24-hour urinalysis revealed urinary loss of glucose, amino acids, uric acid, and potassium. The presence of these multiple defects in renal proximal tubular reabsorption, including glycosuria, hypophosphatemia, and proteinuria, were suggestive of Fanconi syndrome (). Treatment of isotonic saline with electrolyte replacement was maintained. However, the electrolyte imbalance was not corrected, and the metabolic acidosis was aggravated by this treatment. Nine days after chemotherapy, the patient died of uncorrected metabolic acidosis.