CT appearance of long-term renal transplant rejection

Abstract

Computed tomography in a patient with long-term renal transplant rejection demonstrated diffuse renal calcification and perirenal abscess that were subsequently confirmed pathologically. Calcification in the rejected transplant kidney has not been documented by CT before. Computed tomography of the pelvis was done to visualize the status of the renal transplant and to elicit the nature of the swelling. On CT, there were areas of curvilinear and punctate calcifications (Figure 1A) in the kidney and an inflammatory mass around the transplanted kidney, mostly on the inferior and lateral aspects. A collection of fluid approximately 3 cm in diameter, with a CT density of + 1.3 units ( 500 air I + 500 bone), was seen arising from the lower pole of the calcified kidney (Figure 1B). A diagnosis of diffuse calcification in a rejected transplant kidney and an abscess arising from a rejected transplanted kidney was made. Causes of diffuse renal cortical calcification include renal cortical necrosis, chronic glomerulonephritis, and rejected renal transplants, as recently reported (1). Only 2 cases of diffuse cortical calcification of rejected renal transplants have been reported in the literature; the CT finding of calcification in a rejected renal transplant has not been previously reported. A plain film of the pelvis barely revealed the renal calcification, and linear tomography showed faint calcification in a shrunken transplanted kidney (Figure 2).