Kidney obstruction might be caused by a stone in the urinary tract. In case of accompanying fever or renal failure, an urgent drainage might be needed. This can be done either by placing an ureteral stent or a nephrotomy tube. Only limited number of studies examined the question which of the two is preferred. A debate exist regarding the effectiveness of each procedure to improve symptoms, renal function and treating an infection. Our goal is to resolve this debate and to state whether one way is preferred on the other.

Inclusion Criteria: Patient suffering from obstructed kidney by a stone and at least one of these situations:

1. fever (above 38c)
2. A rise in creatine to above 1.5
3. Pain resistent to multiple analgetic treatments

Exclusion Criteria:

• Patients with medical condition that prevent the use of one of the procedures