[Acquired Fanconi-de Toni-Debre syndrome due to therapy for Ewing's sarcoma in 5-years old boy].

We present a 5-years old boy with acquired Fanconi-de Toni-Debre syndrome being a effect of therapy for Ewing's sarcoma. At the age of 3 years, this boy was diagnosed as suffering from Ewing sarcoma of his right femur. The boy received a course of 8-month pre-surgery (6 VIDE--Vincristine, Ifosfamide, Doxorubicin, Etoposide cycles and 2 VAI--Vincristine, Actinomycin, Ifosfamide cycles) and 6-month post-surgery (6 VAI--Vincristine, Actinomycin, Ifosfamide cycles) cytostatic therapies according to EWING, EURO 99 protocol. In forth month of post-surgery cytostatic therapy, progressive malaise, polyuria, polydypsia, and recurrent vomiting occurred. The association between those symptoms and malignancy was excluded. Laboratory studies revealed hypokaliemia, hypophosphatemia, proximal tubular acidosis, proteinuria, glucosuria, aminoaciduria, hyperkaliuria and hyperphosphaturia. Acquired Fanconi-de Toni-Debre syndrome due to toxic effect of cytostatic therapy on renal proximal tubules was diagnosed. At present, two years after the time the diagnosis was made, despite constant substitution of potassium, phosphates and bicarbonates, deficit of body mass and height, and bone mineral density abnormalities are observed.