From the Guidelines
Hydronephrosis typically decreases glomerular filtration rate (GFR) due to the obstruction of urine flow, which increases pressure within the kidney and impairs blood flow to the nephrons. This condition can lead to acute kidney injury and, if not corrected, permanent nephron loss 1. The severity of GFR reduction depends on the degree and duration of obstruction. Key points to consider include:
- The obstruction caused by hydronephrosis increases pressure within the kidney, compressing the renal parenchyma and impairing blood flow to the nephrons.
- The increased pressure directly affects the filtration process in the glomeruli, leading to a decrease in GFR.
- Initially, there may be a compensatory increase in GFR in the unaffected kidney, but as hydronephrosis progresses, especially if bilateral, overall GFR declines.
- Acute hydronephrosis may cause reversible GFR reduction, while chronic hydronephrosis can lead to permanent kidney damage and function loss, as noted in the context of asymptomatic hydronephrosis in pregnancy, which can become symptomatic and lead to severe outcomes if left untreated 1.
- Prompt treatment of the underlying cause of hydronephrosis is essential to prevent permanent GFR reduction and preserve kidney function, highlighting the importance of early diagnosis and intervention.
From the Research
Effect of Hydronephrosis on GFR
- Hydronephrosis can lead to a decline in renal function, including a decrease in Glomerular Filtration Rate (GFR) 2, 3.
- The decrease in GFR is due to the obstruction of the urinary tract, which can cause damage to the renal parenchyma and lead to a decline in renal function 4.
- Treatment of hydronephrosis, such as percutaneous nephrostomy or ureteral stenting, can help to improve renal function and prevent further decline in GFR 2, 5, 3.
- Studies have shown that percutaneous nephrostomy can be an effective treatment for hydronephrosis, with a high success rate and low complication rate 2, 5.
- Ureteral stenting can also be an effective treatment, but may be associated with more complications, such as stent migration and urinary tract infection 5, 6.
Treatment Options for Hydronephrosis
- Percutaneous nephrostomy: a minimally invasive procedure that involves the insertion of a catheter into the kidney to drain the urine 2, 5, 3.
- Ureteral stenting: a procedure that involves the insertion of a stent into the ureter to drain the urine 5, 3, 6.
- Pyeloplasty: a surgical procedure that involves the repair of the ureteropelvic junction to relieve the obstruction 6.