Figure 2b. Renal urine leak in a 57-year-old man with oliguria and renal insufficiency. The patient had undergone renal transplantation 1 week earlier. (a) CT scan of the right lower quadrant of the transplanted kidney demonstrates a fluid collection medial to the right ureteropelvic junction (arrow). (b) Sequential dynamic images obtained at renal scintigraphy with technetium-99m dimercaptosuccinic acid help confirm an anastomotic leak at the level of the transplant ureteropelvic junction, with progressive accumulation of radiotracer outside the collecting system over time (arrows).