Related Experiment Videos
Low grade pelviureteric junction obstruction with normal diuretic renography
British Journal of Urology
|August 1, 1986
Summary
A normal diuretic renogram may miss low-grade ureteropelvic junction obstruction. Whitaker testing at both low and high flow rates is recommended for accurate diagnosis of renal obstruction.
Area of Science:
- Urology
- Nephrology
- Diagnostic Imaging
Background:
- Diuretic renography is a standard tool for evaluating potential ureteropelvic junction (UPJ) obstruction.
- However, its sensitivity in detecting subtle or low-grade obstruction can be limited.
Observation:
- Five patients with initially normal diuretic renograms underwent Whitaker pressure perfusion testing.
- These patients exhibited normal pressure gradients at low flow rates (2-4 ml/min).
- Abnormally elevated pressures were observed at higher flow rates (8-10 ml/min).
Findings:
- A negative diuretic renogram in well-hydrated patients with good renal function may not exclude low-grade UPJ obstruction.
- Whitaker testing revealed elevated pressures specifically at high flow rates, indicating a functional obstruction.
Implications:
- Enhanced diagnostic protocols are needed for suspected UPJ obstruction.
- Renal pelvic perfusion assessment at both low and high flow rates during Whitaker testing improves the detection of pelviureteric junction dysfunction.
- This approach can prevent delayed diagnosis and treatment of significant renal obstruction.