TRAS

Case: 54 years old male with history of kidney transplant 10 months ago presented to Emergency department with accelerated hypertension and flash pulmonary edema. On examination, an abdominal bruit over the transplanted site is heard. What is the most probable diagnosis?

Answer: TRAS (Transplant renal artery stenosis)

TRAS can occur in up to one in four renal transplanted recipient patients. It occurs at the site of the renal artery anastomosis. Interestingly, it can also occur in the donor's renal artery or the feeding native artery. The usual causes are difficulty during transplants, causing flow limitation through vascular clamping, kinking, or angulation of the artery. Major clinical signs are:  

• Worsening hypertension
• Unexplained and persistent Hypokalemia (secondary hyperaldosteronism)
• Kidney function decline
• Episodes of flash pulmonary edema
• Abdominal bruit over the allograft (may or may not be present)

The risk factors are

• Difficulties in organ procurement 
• Poor/complex operative techniques 
• Atherosclerotic disease
• Cytomegalovirus infection
• Delayed allograft function 

 Fortunately, it is reversible. 

#nephrology

#transplantation

References:

1. Audard V, Matignon M, Hemery F, et al. Risk factors and long-term outcome of transplant renal artery stenosis in adult recipients after treatment by percutaneous transluminal angioplasty. Am J Transplant 2006; 6:95.

2. Bruno S, Remuzzi G, Ruggenenti P. Transplant renal artery stenosis. J Am Soc Nephrol 2004; 15:134.

3. Voiculescu A, Schmitz M, Hollenbeck M, et al. Management of arterial stenosis affecting kidney graft perfusion: a single-centre study in 53 patients. Am J Transplant 2005; 5:1731.

4. Pouria S, State OI, Wong W, Hendry BM. CMV infection is associated with transplant renal artery stenosis. QJM 1998; 91:185.