Enlarged photon-deficient area in expected site of renal allograft on Tc-99m DTPA study. A sign of renal vein thrombosis.

Tc-99m DTPA renal imaging has been routinely used in postrenal transplant evaluation. A patient's Tc-99m DTPA studies after transplantation are presented, showing a large photon-deficient area in the region of the allograft on the third postoperative day. The photon-deficient area is two to three times larger than that seen in the original, functioning allograft on the first postoperative day. Enlarged to a weight of 530 g, the allograft on gross and microscopic examination confirmed renal vein thrombosis. Enlargement of the photon-deficient area at the anatomic site of the allograft indicates a scintigraphic pattern of renal vein occlusion incompatible with a viable allograft.