Objectives: To evaluate the Whitaker test, a pressure flow examination, for its prognostic value in dilated renal transplants because urologic complications, such as ureteral stenosis, are significant problems after kidney transplantation.
Methods: Twenty-five patients with obstruction of the renal transplant and subsequent percutaneous nephrostomy were evaluated with a urodynamic pressure flow test (Whitaker test) in combination with antegrade pyeloureterography. The results of the Whitaker test were related to the serum creatinine values.
Results: The Whitaker test demonstrated normal pressure flow (less than 15 cm H(2)O) in 7 patients, pressure flow between 15 and 25 cm H(2)O in 10, and pathologic results (greater than 25 cm H(2)O) in 8 patients. After percutaneous nephrostomy, the serum creatinine level decreased in 22 of 25 patients, although the urodynamic pressure flow revealed a significant obstruction (Whitaker test greater than 25 cm H(2)O) in only 8 patients. The sensitivity of the Whitaker test to indicate the relevance of post-renal transplant stenosis in comparison to the declining serum creatinine level after successful percutaneous nephrostomy was 79%; the specificity was 50%.
Conclusions: The results of our study indicate that a decreasing creatinine level in correlation with radiologic results is the leading finding in dilation of transplanted kidneys without rejection. The Whitaker test, as a pressure flow examination, provided no additional information.