Renal Transplant Rejection

Imaging

• No specific imaging characteristics

• Ultrasound-guided renal biopsy is gold standard

• Acute rejection (AR): Nonspecific allograft edema, urothelial thickening

• Resistive index (RI) may be elevated, or there may be loss or reversal of arterial diastolic flow

• Elevated RI > 0.80 in early postoperative period associated with increased risk of graft failure

• Chronic rejection (CR): Cortical atrophy, increased echogenicity, calcification

• Color perfusion may be decreased in both AR or CR