Case report of transplant renal artery stenosis secondary to mechanical renal artery kinking: Balloon angioplasty as a supportive diagnostic tool?

INTRODUCTION AND IMPORTANCE: Renal vascular complications are a significant cause of morbidity in living donor renal transplantation. Among renal vascular complications, transplant renal artery stenosis (TRAS) secondary to mechanical kinking is a rare but important cause of early graft dysfunction. Identifying this phenomenon and correcting the underlying cause is critical to graft viability in the post-operative period. This case illustrates the importance of balloon angioplasty in identifying this complication and prompting surgical correction. CASE PRESENTATION: We describe the case of a 67-year-old male who received a right-sided living donor kidney graft for Stage IV Chronic Kidney Disease secondary to biopsy proven Ig-A nephropathy. In the post-operative course, serum creatinine remained elevated and Doppler showed low-normal vascular flow velocities. Renal angiogram indicated transplant renal artery stenosis secondary to the rare phenomenon of mechanical kinking. Findings noted during unsuccessful angioplasty supported the diagnosis and surgical repositioning of the graft provided definitive repair. Post-operative serum creatine trended down and urine output improved within 24 h. Patient was stable at two month follow up. CLINICAL DISCUSSION: Transplant renal artery stenosis secondary to mechanical kinking can cause significant graft dysfunction in the post operative period. Previous case reports and literature review has found balloon angioplasty to be ineffective in correcting this underlying cause of TRAS. In line with previous reports, balloon angioplasty failed to correct the stenosis; however, this provided additional diagnostic information by identifying the kink and prompting surgical repair. CONCLUSION: Transplant renal artery stenosis secondary to mechanical kinking can be difficult to identify by renal angiogram alone. Attempted balloon angioplasty can confirm the diagnosis and prompt definitive surgical repair.