A 54-year-old man is 18 months post kidney transplant. He presents with headaches and oliguria. Serum creatinine is 2.5 mg/dL from a baseline of 1.32 post transplant. His blood pressure is 190/101 mm Hg. He has no focal neurological signs. On reviewing his operative note from the kidney transplant, you note that the renal allograft was deemed a “difficult procurement,” and his postoperative course was complicated by delayed graft function (DGF). Biopsy is not consistent with rejection.
Which of the following is the next best step in workup of this patient?A. CT abdomen
Correct Answer: D
Transplant renal artery stenosis (TRAS) usually occurs between 3 months and 2 years after renal transplantation, but it can present at any time. It is a potentially curable cause of posttransplant hypertension, allograft dysfunction, and graft loss. Renal artery stenosis usually occurs close to the allograft renal artery surgical anastomosis. Risk factors include difficulties in procurement and surgical technique, atherosclerotic disease, cytomegalovirus infection, and DGF. It presents in most cases as refractory hypertension and allograft dysfunction. Although noninvasive imaging modalities such as Doppler ultrasonography, spiral computed tomography, and magnetic resonance angiography are useful in screening for TRAS, arteriography is the definitive diagnostic and treatment modality when TRAS is suspected based on noninvasive tests or clinical presentation. Once identified by arteriography, the stenosis can be corrected directly with angioplasty and stenting. It is important to rule out rejection before arteriography to optimize chances of graft function recovery.