Percutaneous Therapy for Renal Artery Fibromuscular Dysplasia

Fibromuscular dysplasia (FMD) accounts for 10% of cases of renal artery stenosis. This study evaluates the anatomic and functional outcomes of endovascular therapy for symptomatic renal artery FMD at an academic medical center. A retrospective analysis of records from patients who underwent percutaneous transluminal renal artery angioplasty (PTRA) found 14 patients (all female) who underwent 19 interventions on 18 renal artery segments. Significant cardiovascular comorbidities were few in this patient population. The PTRA technical success rate was 95%. There were no periprocedural mortalities. Primary patency rates were 81%, 69%, 69%, and 69% at 2, 4, 6, and 8 years. Assisted primary patency rates were 87%, 87%, 87%, and 87% at 2, 4, 6, and 8 years. The restenosis rate was 25% at 8 years. Clinical benefit (improved or cured hypertension) was seen in 79% of patients overall; 65% of patients maintained this benefit at 8 years by life-table analysis. Percutaneous endovascular intervention for clinically symptomatic FMD of the renal arteries is technically successful, safe, and durable. Most patients demonstrate immediate clinical benefit and retain durable functional outcomes. Presented at the Thirteenth Annual Winter Meeting of the Peripheral Vascular Surgery Society, Snowmass, CO, January 31-February 2, 2003.     

Long-term Results After Surgical Reconstruction for Renal Artery Fibromuscular Dysplasia

OBJECTIVES: To study the initial and long-term results of surgery for renal artery fibromuscular dysplasia (RFMD). PATIENTS AND METHODS: All patients undergoing renal artery reconstruction (RAR) performed for RFMD between January 1980 and December 1997, were studied. The preprocedural and postprocedural clinical records of 101 patients (80 women, 21 men; mean age at surgery 43 years) were retrospectively reviewed. All surviving patients were invited for clinical reexamination and colour-coded duplex-ultrasound of the renal arteries (RA). RESULTS: Initial technical success was achieved in 83 of 93 patients (89%), in whom postoperative angiography (90) or renal scintigraphy (three) were performed for assessment of RAR. Early occlusion (four) or stenosis (one) demanded reoperation in five patients (5%). The 30-day mortality and morbidity were 2% and 12% for the entire group. Primary patency rate was 74% at 5 years. Fifteen patients had to be reoperated for restenosis after a mean time of 33 months, resulting in a secondary patency rate of 85% after 5 years. In 61 patients with patent RAR at the time of re-examination, arterial hypertension was cured only in 22 (36%) and improvement in 19 (31%). CONCLUSION: Vascular surgery for RFMD yields good long-term results as to kidney perfusion and function. Surveillance of RAR-patency by means of ultrasound examination is mandatory in case of recurrence of arterial hypertension or deterioration. Rates of cure of hypertension are disappointing.     

Renal Artery Aneurysm Secondary to Fibromuscular Dysplasia in a Young Patient

An 8-year-old male was found on routine physical examination to have a blood pressure of 220/110. Renal angiography demonstrated bilateral renal artery stenosis and an aneurysm of the distal left renal artery with branch involvement. At operation, the left renal artery stenosis and aneurysm was repaired by ex vivo arterial reconstruction and autotransplantation of the kidney. Pathologic evaluation of the resected aneurysm confirmed the diagnosis of fibromuscular dysplasia. Fibromuscular dysplasia is the most common cause of renal artery stenosis in children over 1 year of age and can in rare cases be associated with the development of renal artery aneurysms. In complex cases of renal artery stenosis with involvement of renal artery branches, ex vivo repair and orthotopic autotransplantation is an excellent approach for surgical management.Presented at the Twenty-second Annual Meeting of the Southern California Vascular Surgery Society, La Jolla, CA, April 30-May 2, 2004.     

Renal Transplantation for Fibromuscular Dysplasia

This is the first report that presents renal transplantation after bilateral nephrectomy as the final treatment for severe renovascular hypertension due to fibromuscular dysplasia (FMD). We describe the history of a 1‐year‐old girl who suffered from renovascular hypertension due to FMD. Imaging revealed multiple bilateral stenoses of the renal artery extending into the distal branches. The hypertension proved unresponsive to pharmacologic treatment and the intrarenal peripherally located stenoses rendered a conventional approach such as transluminal or surgical angioplasty not feasible. At the age of 5 years, a unilateral nephrectomy of the most affected kidney was performed, but she remained hypertensive and developed progressive cardiomyopathy and retinopathy. At the age of 6 years the remaining kidney was removed, followed by a living related renal transplantation with a kidney donated by her mother. Posttransplantation, she developed mild hypertension due to a postanastomotic stenosis, which was easily controlled with antihypertensives. Now 8 years after transplantation, she has experienced no further blood pressure related problems. Although there is a risk of recurrence of FMD after performing a living related transplantation, our report suggests that this procedure is relatively safe, provided appropriate preoperative evaluation and follow up is performed.     

Rapid Resolution of Proteinuria of Native Kidney Origin Following Live Donor Renal Transplantation

To assess the contribution of the protein content of urine from the native kidneys to post-transplant proteinuria, we prospectively studied 14 live donor transplant recipients with a pre-transplant random urine protein to creatinine ratio (UPr:Cr) >0.5. Seven patients received preemptive transplants, and seven patients were on dialysis pre-transplant (with residual urine output). Resolution of proteinuria was defined as UPr:Cr < 0.2. Immunosuppression consisted of tacrolimus, mycophenolate mofetil and corticosteroids. Anti-hypertensive drugs that might reduce proteinuria were avoided during the study. The serum creatinine was 8.7 +/- 0.7 mg/dL pre-transplant, and the nadir post-transplant serum creatinine was 1.4 +/- 0.1 mg/dL. The pre-transplant UPr:Cr ranged between 0.5 and 9.2 (mean = 2.9 +/- 0.6). The UPr:Cr decreased to <0.2 in all 14 patients at a mean of 4.5 weeks post-transplant (range 1-10 weeks). In conclusion, in live donor renal transplant recipients with immediate graft function, proteinuria of native kidney origin resolves in the early post-transplant period. After the immediate post-transplant period, proteinuria cannot be attributed to the native kidneys, and work up for proteinuria should focus on the allograft.     

Renal Cell Carcinoma on the Native Kidney Following Kidney Transplantation

A 48-year-old man with histories of IgA nephropathy for 33 years, hemodialysis for 29 years, and a kidney transplant from a deceased donor 5 years ago was admitted to our institute complaining of high fever and back pain. Although repeated follow-up of computed tomography failed to detect any de novo issues, he was eventually diagnosed as a renal cell carcinoma with multiple metastases, developing from his native-acquired cystic disease kidney with multiple cysts using a positron emission tomography. We should be cautious of de novo renal cell carcinoma in kidney transplantation recipients, and careful follow-up might be helpful to detect it.     

Successful Kidney Transplantation Using a Deceased Donor Graft With Fibromuscular Dysplasia

All over the world there is serious concern about the shortage of organs available for transplantation. In an effort to address this, transplantation with grafts, which was previously considered a contraindication, are now performed. In some cases, this practice has contributed to increasing the organ pool. Fibromuscular dysplasia (FMD) is the second-most-common cause of renovascular hypertension and is observed in 2%–6.6% of potential live kidney donors. Kidney with FMD is generally considered to be a contraindication for renal transplantation because renal artery stenosis may progress after transplantation and cause graft loss. Here, we report on a successful case of kidney transplantation using a graft with FMD of a deceased donor who had multiple aneurysms in the renal artery.     

Outcomes and Native Renal Recovery Following Simultaneous Liver–Kidney Transplantation

With the increase in patients having impaired renal function at liver transplant due to MELD, accurate predictors of posttransplant native renal recovery are needed to select candidates for simultaneous liver–kidney transplantation (SLK). Current UNOS guidelines rely on specific clinical criteria for SLK allocation. To examine these guidelines and other variables predicting nonrecovery, we analyzed 155 SLK recipients, focusing on a subset (n = 78) that had post‐SLK native GFR (nGFR) determined by radionuclide renal scans. The 77 patients not having renal scans received a higher number of extended criteria donor organs and had worse posttransplant survival. Of the 78 renal scan patients, 31 met and 47 did not meet pre‐SLK UNOS criteria. The UNOS criteria were more predictive than our institutional criteria for all nGFR recovery thresholds (20–40 mL/min), although at the most conservative cut‐off (nGFR ≤ 20) it had low sensitivity (55.3%), specificity (75%), PPV (67.6%) and NPV (63.8%) for predicting post‐SLK nonrecovery. On multivariate analysis, the only predictor of native renal nonrecovery (nGFR ≤ 20) was abnormal pre‐SLK renal imaging (OR 3.85, CI 1.22–12.5). Our data support the need to refine SLK selection utilizing more definitive biomarkers and predictors of native renal recovery than current clinical criteria.     

Renal Consequences of Diabetes After Kidney Donation

Whether diabetes after kidney donation is associated with an accelerated GFR decay in the remaining kidney has not been studied. We determined the incidence of diabetes in kidney donors, and compared GFR change over time in diabetic to nondiabetic donors, in addition to the effect of diabetes mellitus (DM) on the development of proteinuria, hypertension, and end‐stage renal disease (ESRD). Of the 4014 donors, 309 (7.7%) developed diabetes at a median age of 56.0 years and after a median of 18 years after donation. The difference in annual estimated GFR (eGFR) change between diabetic and nondiabetic donors in the 7 years before the development of DM was ?0.08 mL/min/year; p = 0.51. After DM development, the difference was ?1.10 mL/min/year for diabetic donors with hypertension and proteinuria, p < 0.001; ?0.19 for diabetic donors with hypertension but no proteinuria, p = 0.29; ?0.75 mL/min/year for diabetic donors with proteinuria but no hypertension, p = 0.19; and ?0.09 mL/min/year for diabetic donors without proteinuria or hypertension, p = 0.63. When DM was considered as a time‐dependent covariate, it was associated with the development of proteinuria (hazard ratio [HR] 2.65, 95% confidence interval [CI] 1.89–3.70; p < 0.001) and hypertension (HR 2.19, 95% CI 1.74–2.75; p < 0.001). It was not, however, associated with ESRD. eGFR decline after DM development exceeds that of nondiabetic donors only in diabetic donors with concomitant proteinuria and hypertension.     

Surgical Management of Renal Fibromuscular Dysplasia: Challenges in the Endovascular Era

Percutaneous transluminal renal angioplasty (PTRA) is the primary treatment for renal fibromuscular dysplasia (RFMD). Surgical revascularization is limited to patients who fail or are unsuitable for PTRA. All patients who were operated on with RFMD since the indications for renal PTRA were expanded in our institution were retrospectively reviewed. Outcome included patency, hypertension, and renal function. Twenty-six patients had reconstruction of 32 renal arteries between 1998 and 2004. The mean age was 47.1±14 years; the majority (81%) were female. Six patients had bilateral disease and three had a solitary kidney. Operations were done for hypertension in 25 patients, renal artery aneurysm in 8, and chronic dissection in 1, alone or in combination. Six patients had a failed PTRA and 20 were unsuitable for it. Aortorenal bypass was done most often (n=28) and saphenous vein was the preferred conduit (n=25). The distal anastomosis was to the main renal artery in 13 patients and to the branch arteries in 19. Ex vivo repair was needed in five patients. Five intraoperative revisions were done because of abnormalities on duplex scan. One patient died unexpectedly 42 days after operation from myocardial infarction. Extrarenal complications occurred in five patients. Median follow-up was 2.4 (range, 42 days to 6.3) years and was available in all but one patient (96%). Two bypasses occluded at 3 and 376 days, which resulted in loss of the kidneys. One graft stenosis was treated successfully with PTRA at 239 days. All failures occurred in men. One-year cumulative primary patency was 89±8% and was not adversely affected by prior PTRA or complex repair. Hypertension at 1 year was cured in 27% of the patients and improved in 60%. No patient developed acute or chronic renal failure. Surgical reconstruction for RFMD has excellent short-term patency. Failed PTRA or complex reconstructions did not adversely affect outcome.Presented at the Twenty-ninth Annual Meeting of the Peripheral Vascular Surgery Society, Anaheim, CA, June 4-5, 2004.     

Isolated Iliac Artery Aneurysm Caused by Fibromuscular Dysplasia: Report of a Case

Fibromuscular dysplasia (FMD) can develop in many different arteries, but iliac artery aneurysms are rare. A 69-year-old Japanese woman was admitted to our hospital for treatment of a right common iliac artery aneurysm. Aortography revealed aneurysms in both the right common iliac artery and the left internal iliac artery. Notably, the right common iliac artery aneurysm had a string-of-beads appearance. At surgery, the aneurysms were resected, and replaced with Y-shaped vascular prostheses. The histopathological diagnosis was fibromuscular dysplasia (FMD). We report this case of common iliac artery aneurysm caused by FMD due to its rarity.