Effect of Nephrostomy on Relative Function of Obstructed Kidney

The Effect of Percutaneous Nephrostomy Application on Obstructed Kidneys With Relative Function of 10% or Less In Technetium-99m Dimercaptosuccinic Acid (DMSA) Scintigraphy

Urinary tract obstruction is a serious health problem due to kidney damage. Relative renal function has an important role in the treatment of obstructed kidneys. Nephrectomy can be recommended when the relative renal function is 10% or less in radionuclide examinations. Recently, however, nephron sparing approaches have come to the fore. This indicated the need to evaluate the possibility of recovering the function of the kidney before nephrectomy. The aim of this study is to compare relative functions of obstructed kidneys in technetium 99m dimercaptosuccinic acid scintigraphy (DMSA) before and 2 weeks after nephrostomy tube.

Obstructive uropathy is one of the most important causes of acute renal injury and end-stage renal failure. obstruction of urine flow increases the intratubular pressure. This pressure increase causes decrease in renal blood flow and starts the inflammatory process. In the first few hours after total ureter obstruction, due to the increase in intratubular pressure glomerular filtration ceases and tubular transport is markedly decreased. Long lasting obstruction results in renal fibrosis and end stage renal damage. Basically obstructive uropathy leading to irreversible renal damage and loss of renal function is the main indication for simple nephrectomy. Serious renal parenchymal damage is defined as non-functioning kidney having relative renal function (RRF) 10% or less in the literature. But recently in some studies it was suggested that by applying the nephrostomy catheter, ability of kidney to regain function can be evaluated before nephrectomy. So, possibility of gaining function should be kept in mind. In this study effect of percutaneous nephrostomy tube on serum creatinine, blood urea nitrogen (BUN) and RRF in obstructed kidney with RRF 10% or less. Before and 2 weeks after percutaneous nephrostomy, serum creatinine, ure and RRF in DMSA was recorded and compared.

Inclusion Criteria:

• Unilateral obstructed kidney with RRF 10% or less
• Unilateral obstructed kidney with grade 2 or more hydroureteronephrosis
• Defined etiology for unilateral obstructed kidney
• estimated glomerular filtration rate (GFR) ≥ 30ml/min
• Approving the nephrostomy procedure

Exclusion Criteria:

• Unilateral obstructed kidney with RRF above 10%
• Estimated GFR <30 ml/min
• diagnosis of bilateral obstructed kidneys
• not approving nephrostomy