The Whitaker test, a useful tool in renal grafts?

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.

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.

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%.

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.