A study of ureteral blockage by Candida in a patient suffering from urinary derivation is presented. It has been favourably resolved by medical treatment and nephrostomy. The increasing medical importance of urinary infections by fungi, especially in weak patients and catheter carriers, makes it important to employ more aggressive treatment. Regarding urinary derivation and Candida infection, in the case of urinary blockage the possibility must be considered that blockage may be due to fungi, since it can be successfully treated medically without the need of surgery.