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Renal artery stenosis and aneurysms associated with neurofibromatosis

2005; Elsevier BV; Volume: 41; Issue: 3 Linguagem: Inglês

10.1016/j.jvs.2004.12.021

1097-6809

Myo Han, Enrique Criado,

Renal cell carcinoma treatment

Renal artery lesions associated with neurofibromatosis may involve stenosis and aneurysm formation at all levels of the renal artery to the intraparenchymal branches, and usually are associated with hypertension. A 13-year-old boy with type I neurofibromatosis and severe hypertension presented with multiple aneurysms and multiple stenotic lesions in the renal artery and segmental arteries. The patient underwent ex-vivo renal artery repair with autologous hypogastric artery and autotransplantation to the iliac fossa and was clinically improved. The characteristic histologic findings are presented. A review of the recent literature comparing different treatment modalities for renovascular hypertension in children with neurofibromatosis suggests that surgery remains the best treatment alternative. Renal artery lesions associated with neurofibromatosis may involve stenosis and aneurysm formation at all levels of the renal artery to the intraparenchymal branches, and usually are associated with hypertension. A 13-year-old boy with type I neurofibromatosis and severe hypertension presented with multiple aneurysms and multiple stenotic lesions in the renal artery and segmental arteries. The patient underwent ex-vivo renal artery repair with autologous hypogastric artery and autotransplantation to the iliac fossa and was clinically improved. The characteristic histologic findings are presented. A review of the recent literature comparing different treatment modalities for renovascular hypertension in children with neurofibromatosis suggests that surgery remains the best treatment alternative. Neurofibromatosis is an autosomal dominant disorder with various manifestations that may include vascular lesions, such as renal arterial stenosis and aneurysm formation, and aortic coarctation. Although pheochromocytoma is a common cause of severe hypertension in adult patients with neurofibromatosis, renal artery stenosis is more likely the cause of hypertension in children with this disease.1Elias D.I. Ricketts R.R. Smith R.B. Renovascular hypertension complicating neurofibromatosis.Am Surg. 1985; 2: 97-106Google Scholar In the present report, we describe the case of a 13-year-old boy with neurofibromatosis and renovascular hypertension who was found to have severe right renal artery stenoses and aneurysms. In addition, we discuss our review of the literature with emphasis on renal artery lesions, histologic findings, and treatment outcomes. A 13-year-old boy with type I neurofibromatosis presented with chronic, poorly controlled hypertension with systolic and diastolic pressures >95th percentile for age and height. A magnetic resonance angiogram showed right renal artery stenosis, with focal distal dilatations and stenoses, and retroperitoneal neurofibromas. No adrenal lesions were noted. High doses of medication improved, but did not normalize, his blood pressure and were associated with frequent headaches and nausea. Aortography showed a severe stenosis with poststenotic dilatation of the right renal artery and stenoses and small aneurysms in the segmental arteries (Fig 1). The contralateral renal artery was normal, and no other vascular anomalies were visualized. On physical examination, the patient presented multiple café-au-lait skin macules and a subcutaneous neurofibroma in his thigh. His abdominal and vascular examination was unremarkable. The laboratory values for his preoperative serum creatinine, blood cell count, urinalysis, serum electrolytes, urine catecholamines, vanilmandelic acid, and metanephrines were normal. Renal vein renin sampling was nondiagnostic. The patient underwent ex-vivo surgical repair with autotransplantation to the right iliac vessels. Through a transverse abdominal incision, the right colon was mobilized and the right hypogastric artery with three distal branches was harvested. The kidney and ureter were mobilized, and the renal artery and vein were ligated and transected. The kidney was brought to the surface of the wound and placed in ice slush. The renal artery was flushed with 1 liter of University of Wisconsin solution at 4°C. The ureter was clamped with a soft, rubber jaw clamp to prevent renal rewarming via the ureteral vessels. All branches of the renal artery were dissected to the parenchyma, and all stenotic and aneurismal segments were resected. Three segmental branches were transected at the junction with the renal parenchyma and still were found to have an abnormal wall. The branches of the harvested hypogastric artery were anastomosed to the hilar branches with interrupted 8–0 polypropylene sutures. An upper pole renal artery branch was anastomosed to the hypogastric artery. Because most of the native renal artery was resected and the harvested hypogastric artery was not long, it was determined that the reconstructed renal artery would fit better reanastomosed to its origin off the iliac artery, and the renal vein to the external iliac vein. No blood was transfused. Urine output resumed immediately after the kidney was reperfused. An esmolol drip was required during the first postoperative day, and the patient remained normotensive without medication for 6 days. On postoperative day 7, an arteriogram revealed patency of the arterial reconstruction with some residual stenoses of the intraparenchymal arteries and an occluded segmental branch anastomosis to a severely diseased artery, but revision was not considered worthwhile (Fig 2). The patient's blood pressure slightly increased on postoperative day 7, and he was discharged on oral β-blockers. His serum creatinine level remained normal. At 16 months of follow-up, the patient's blood pressure was well controlled with lower doses of medication compared with preoperative doses. He remained asymptomatic and doing well in school. Histologic examination is presented in Fig 3, Fig 4.Fig 4Renal artery aneurysm with elastin trichrome stain demonstrating outpouching of the vessel wall with intimal proliferation, and attenuation of the media and elastic lamina. Magnification ×40.View Large Image Figure ViewerDownload (PPT) The classic form of type I neurofibromatosis with café-au-lait spots, neurofibromas, and iris hamartomas first described by Von Recklinghausen in 18822Riccardi V.M. Von Recklinghausen neurofibromatosis.N Engl J Med. 1981; 305: 1617-1627Crossref PubMed Scopus (948) Google Scholar is the type most often associated with vascular lesions.1Elias D.I. Ricketts R.R. Smith R.B. Renovascular hypertension complicating neurofibromatosis.Am Surg. 1985; 2: 97-106Google Scholar Neurofibromatosis has an estimated incidence of 1 in 3,000 births and is seen worldwide with no ethnic, regional, or gender preference. The pathogenesis of this disease has been linked to a developmental disorder of the neural crest cells.1Elias D.I. Ricketts R.R. Smith R.B. Renovascular hypertension complicating neurofibromatosis.Am Surg. 1985; 2: 97-106Google Scholar Our literature review from the last 10 years found 13 reports comprising 49 patients (24 females/25 males) with neurofibromatosis and renovascular hypertension who were treated with medication, surgery, or percutaneous transluminal angioplasty (PTA) or coil embolization. The ages of these patients ranged from 4 months to 34 years (mean, 11 years). Follow-up ranged from 5 months to 20 years (Table). There were 20 unilateral and 23 bilateral lesions. Associated vascular lesions included 6 renal artery aneurysms, 5 abdominal aortic coarctations, 6 superior mesenteric artery stenoses, 2 celiac artery stenoses, and 1 subclavian stenosis.Table 1Summary of reports on patient outcomes after treatment for renal artery stenoses associated with neurofibromatosisTreatmentLesionCured⁎No longer required antihypertensive medication and remained normotensive for age.Improved†Patient required lower dose or number of antihypertensive medications.Failure‡Patient remained hypertensive after the treatment with the same or higher dose or number of antihypertensive medications.N/RSurgeryUnilateral stenosis62Refs 3Westenend P.J. Smedts F. de Jong M.C. Lommers E.J. Assmann K.J. A 4-year-old boy with neurofibromatosis and severe renovascular hypertension due to renal arterial dysplasia.Am J Surg Pathol. 1994; 18: 512-516Crossref PubMed Scopus (29) Google Scholar, 4Booth C. Preston R. Clark G. Reidy J. Management of renal vascular disease in neurofibromatosis type 1 and the role of percutaneous transluminal angioplasty.Nephrol Dial Transplant. 2002; 17: 1235-1240Crossref PubMed Scopus (58) Google Scholar, 5Chien G.W. Gritsch H.A. Quinones-Baldrich W.J. Simple surgical repair of bilateral renal artery stenosis in a patient with neurofibromatosis.J Urol. 2002; 167: 1811-1812Abstract Full Text Full Text PDF PubMed Google Scholar, 6Nakhoul F. Green J. Angel A. Ofer A. Ben-Izhak O. Lewin M. Renovascular hypertension associated with neurofibromatosis Two cases and review of the literature.Clin Nephrol. 2001; 55: 322-326PubMed Google Scholar, 7Hirayama K. Kobayashi M. Yamaguchi N. Iwabuchi S. Gotoh M. Inoue C. et al.A case of renovascular hypertension associated with neurofibromatosis.Nephron. 1996; 72: 699-704Crossref PubMed Scopus (6) Google Scholar, 8McTaggart S. Gelati S. Walker R.G. Powell H.R. Jones C.L. Evaluation and long-term outcome of pediatric renovascular hypertension.Pediatr Nephrol. 2000; 14: 1022-1029Crossref PubMed Scopus (69) Google Scholar, 9Estepa R. Gallego N. Orte L. Puras E. Aracil E. Ortuno J. Renovascular hypertension in children.Scand J Urol Nephrol. 2001; 35: 388-392Crossref PubMed Scopus (50) Google ScholarUnilateral aneurysm2Mean f/u in 19 pts: 5.6 yrs (range, 0.4–20.4)Bilateral stenosis443Bilateral aneurysm11TOTAL13 (56%)5 (22%)5 (22%)PTAUnilateral stenosis23Refs 4Booth C. Preston R. Clark G. Reidy J. Management of renal vascular disease in neurofibromatosis type 1 and the role of percutaneous transluminal angioplasty.Nephrol Dial Transplant. 2002; 17: 1235-1240Crossref PubMed Scopus (58) Google Scholar, 8McTaggart S. Gelati S. Walker R.G. Powell H.R. Jones C.L. Evaluation and long-term outcome of pediatric renovascular hypertension.Pediatr Nephrol. 2000; 14: 1022-1029Crossref PubMed Scopus (69) Google Scholar, 10Casalini E. Sfondrini M.S. Fossali E. Two-year clinical follow-up of children and adolescents after percutaneous transluminal angioplasty for renovascular hypertension.Invest Radiol. 1995; 30: 40-43Crossref PubMed Scopus (43) Google Scholar, 11Fossali E. Signorini E. Intermite R.C. Casalini E. Lovaria A. Maninetti M.M. et al.Renovascular disease and hypertension in children with neurofibromatosis.Pediatr Nephrol. 2000; 14: 806-810Crossref PubMed Scopus (90) Google Scholar, 12Ing F. Goldberg B. Siegel D. Trachtman H. Bierman F.Z. Arterial stents in the management of neurofibromatosis and renovascular hypertension in a pediatric patient Case report of a new treatment modality.Cardiovasc Intervent Radiol. 1995; 18: 414-418Crossref PubMed Scopus (27) Google Scholar, 13Fossali E. Minoja M. Intermite R. Spreafico C. Casalini E. Sereni F. Percutaneous transluminal renal angioplasty in neurofibromatosis.Pediatr Nephrol. 1995; 9: 623-625Crossref PubMed Scopus (14) Google Scholar, 14Kurien A. John P.R. Milford D.V. Hypertension secondary to progressive vascular neurofibromatosis.Arch Dis Child. 1997; 76: 454-455Crossref PubMed Scopus (46) Google ScholarUnilateral aneurysm1§Embolization.Mean f/u in 15 pts: 2.4 yrs (range, 0.6–9)Bilateral stenosis41No description42TOTAL10 (59%)1 (6%)6 (35%)MedicalUnilateral stenosis121Refs 4Booth C. Preston R. Clark G. Reidy J. Management of renal vascular disease in neurofibromatosis type 1 and the role of percutaneous transluminal angioplasty.Nephrol Dial Transplant. 2002; 17: 1235-1240Crossref PubMed Scopus (58) Google Scholar, 6Nakhoul F. Green J. Angel A. Ofer A. Ben-Izhak O. Lewin M. Renovascular hypertension associated with neurofibromatosis Two cases and review of the literature.Clin Nephrol. 2001; 55: 322-326PubMed Google Scholar, 7Hirayama K. Kobayashi M. Yamaguchi N. Iwabuchi S. Gotoh M. Inoue C. et al.A case of renovascular hypertension associated with neurofibromatosis.Nephron. 1996; 72: 699-704Crossref PubMed Scopus (6) Google Scholar, 8McTaggart S. Gelati S. Walker R.G. Powell H.R. Jones C.L. Evaluation and long-term outcome of pediatric renovascular hypertension.Pediatr Nephrol. 2000; 14: 1022-1029Crossref PubMed Scopus (69) Google ScholarBilateral stenosis31Mean f/u in 4 pts: 7 yrs (range 5–12.8)Bilateral aneurysm1TOTAL05 (56%)2 (22%)2 (22%)N/R, Not reported; PTA, percutaneous transluminal angioplasty. No longer required antihypertensive medication and remained normotensive for age.† Patient required lower dose or number of antihypertensive medications.‡ Patient remained hypertensive after the treatment with the same or higher dose or number of antihypertensive medications.§ Embolization. Open table in a new tab N/R, Not reported; PTA, percutaneous transluminal angioplasty. All patients received medical therapy. Eight patients were treated with medication alone, 10 had a nephrectomy, 13 had surgical revascularization procedures, 16 had a PTA, and 1 patient had transluminal embolization of an aneurysm. The outcome reported in 47 patients is detailed in the Table; however, 4 out of 10 patients reported as successfully treated with PTA did not have significant follow-up.10Casalini E. Sfondrini M.S. Fossali E. Two-year clinical follow-up of children and adolescents after percutaneous transluminal angioplasty for renovascular hypertension.Invest Radiol. 1995; 30: 40-43Crossref PubMed Scopus (43) Google Scholar In our review, we found only one renal artery histology report that showed intimal proliferation of spindle cells in a mucoid matrix, with destruction of the internal elastic membrane and loss or attenuation of the media and fibrosis of the adventitia.3Westenend P.J. Smedts F. de Jong M.C. Lommers E.J. Assmann K.J. A 4-year-old boy with neurofibromatosis and severe renovascular hypertension due to renal arterial dysplasia.Am J Surg Pathol. 1994; 18: 512-516Crossref PubMed Scopus (29) Google Scholar Another report describes an open kidney biopsy with ischemic changes, the absence of proliferative or sclerotic changes, and mild tubular atrophy.7Hirayama K. Kobayashi M. Yamaguchi N. Iwabuchi S. Gotoh M. Inoue C. et al.A case of renovascular hypertension associated with neurofibromatosis.Nephron. 1996; 72: 699-704Crossref PubMed Scopus (6) Google Scholar Hypertension, although uncommon in patients with neurofibromatosis, may be secondary to renal artery stenosis and pheochromocytoma,1Elias D.I. Ricketts R.R. Smith R.B. Renovascular hypertension complicating neurofibromatosis.Am Surg. 1985; 2: 97-106Google Scholar and more rarely, a cerebellar tumor may produce hypertension in patients with neurofibromatosis.15Guthrie G.P. Tibbs P.A. McAllister R.G. Stevens R.K. Clark D.B. Hypertension and Neurofibromatosis.Hypertension. 1982; 4: 894-897Crossref PubMed Scopus (11) Google Scholar The frequency of both pheochromocytoma and renovascular hypertension in neurofibromatosis is probably less than 1%.1Elias D.I. Ricketts R.R. Smith R.B. Renovascular hypertension complicating neurofibromatosis.Am Surg. 1985; 2: 97-106Google Scholar Although pheochromocytoma is a well-known cause of severe hypertension in adults with neurofibromatosis, it is virtually unknown in children; renovascular hypertension is more likely the cause of secondary hypertension in these patients.3Westenend P.J. Smedts F. de Jong M.C. Lommers E.J. Assmann K.J. A 4-year-old boy with neurofibromatosis and severe renovascular hypertension due to renal arterial dysplasia.Am J Surg Pathol. 1994; 18: 512-516Crossref PubMed Scopus (29) Google Scholar The most common cause of renovascular hypertension in patients with neurofibromatosis is renal artery stenosis, but aortic coarctation or extrinsic compression of the renal arteries by retroperitoneal hamartomas may cause hypertension as well.16Criado E. Izquierdo L. Lujan S. Puras E. del Mar Espino M. Abdominal aortic coarctation, renovascular hypertension, and neurofibromatosis.Ann Vasc Surg. 2002; 16: 363-367Abstract Full Text PDF PubMed Scopus (36) Google Scholar Other vascular lesions associated with neurofibromatosis are stenoses of the abdominal aorta or its branches (or both), usually the superior mesenteric, and the celiac artery. In addition, cerebrovascular disease and congenital heart disease have been associated with neurofibromatosis.16Criado E. Izquierdo L. Lujan S. Puras E. del Mar Espino M. Abdominal aortic coarctation, renovascular hypertension, and neurofibromatosis.Ann Vasc Surg. 2002; 16: 363-367Abstract Full Text PDF PubMed Scopus (36) Google Scholar, 17Pollard S.G. Hornick P. Macfarlane R. Calne R.Y. Renovascular hypertension in neurofibromatosis.Postgrad Med J. 1989; 65: 31-33Crossref PubMed Scopus (13) Google Scholar, 18Greene J.F. Fitzwater J.E. Burgess J. Arterial lesions associated with neurofibromatosis.Am J Clin Pathol. 1974; 62: 481-487Crossref PubMed Scopus (237) Google Scholar, 19Salyer W.R. Salyer D.C. The Vascular lesions of neurofibromatosis.Angiology. 1974; 25: 510-519Crossref PubMed Scopus (216) Google Scholar Small artery lesions (<1 mm) in patients with neurofibromatosis were classified by Reubi20Reubi F. Neurofibromatosis et lesions vasculares.Schweiz Med Wochenschr. 1945; 75: 463-465Google Scholar into three types: 1a simple intimal form of 50 to 400 μm arterioles, consisting of concentric intimal proliferation of spindle cells;2an aneurysmal form of 500 to 1000 μm, characterized by thinning and fragmentation of media and elastic lamina; and3a fusocellular form of 100 to 700 μm arterioles, containing proliferative nodules of spindle cells in their walls. Feyrter21Feyrter F. Uber neurome und neurofibromatose nach untersuchungen am menschlichen (magen-darmschlauch).Wien Med Wochenschr. 1948; 98: 287-290PubMed Google Scholar added to the classification an advanced intimal form, showing fibrous thickening of intima and media, and spindle cells throughout the arterial wall. Reubi20Reubi F. Neurofibromatosis et lesions vasculares.Schweiz Med Wochenschr. 1945; 75: 463-465Google Scholar showed that there was no relation between these vascular lesions and neural malformations and described the proliferative nodules as being of connective tissue origin, whereas Feyrter21Feyrter F. Uber neurome und neurofibromatose nach untersuchungen am menschlichen (magen-darmschlauch).Wien Med Wochenschr. 1948; 98: 287-290PubMed Google Scholar linked them to nervous tissue origin. This discrepancy suggests uncertainty in the histogenesis of the proliferative arterial wall lesions associated with neurofibromatosis. The cellular proliferation appears to consist of mesodermal dysplasia with altered fibroblasts and smooth muscle cells.3Westenend P.J. Smedts F. de Jong M.C. Lommers E.J. Assmann K.J. A 4-year-old boy with neurofibromatosis and severe renovascular hypertension due to renal arterial dysplasia.Am J Surg Pathol. 1994; 18: 512-516Crossref PubMed Scopus (29) Google Scholar, 18Greene J.F. Fitzwater J.E. Burgess J. Arterial lesions associated with neurofibromatosis.Am J Clin Pathol. 1974; 62: 481-487Crossref PubMed Scopus (237) Google Scholar, 22Finley J.L. Dabbs D.J. Renal vascular smooth muscle proliferation in neurofibromatosis.Hum Pathol. 1988; 19: 107-110Abstract Full Text PDF PubMed Scopus (50) Google Scholar The vascular lesions described in our patient exhibited a combination of the previously described characteristics. The main renal artery exhibited both the aneurysmal form, with thinning of media and elastic lamina, and the nodular proliferations of spindle cells, with marked increased in the mucoid matrix of the media and intima. However, the smaller hilar renal artery branch showed a marked intimal proliferation consistent with the simple intimal form. Interestingly, a segment of hypogastric artery also revealed similar, although minor, histologic changes. It probably reflects the widespread vascular involvement with neurofibromatosis in our patient. Renal artery lesions associated with neurofibromatosis can be similar to those found in fibromuscular dysplasia. In the latter disease, it is usually the main renal artery and the proximal branches that are involved, and the elastic lamina, media, and fibrous elements of the media undergo hyperplastic and disruptive changes.3Westenend P.J. Smedts F. de Jong M.C. Lommers E.J. Assmann K.J. A 4-year-old boy with neurofibromatosis and severe renovascular hypertension due to renal arterial dysplasia.Am J Surg Pathol. 1994; 18: 512-516Crossref PubMed Scopus (29) Google Scholar, 18Greene J.F. Fitzwater J.E. Burgess J. Arterial lesions associated with neurofibromatosis.Am J Clin Pathol. 1974; 62: 481-487Crossref PubMed Scopus (237) Google Scholar Involvement of the intrarenal or hilar branches and of the renal artery ostium, and the presence of proliferative nodules, are characteristic of neurofibromatosis, a differentiating feature from fibromuscular dysplasia. Because vascular lesions in neurofibromatosis involve both large and small vessels, it is difficult to determine the contribution of each type to the hypertensive state. Renal end-organ damage secondary to sustained hypertension and diffuse, intrarenal vessel involvement, as described in our patient, may preclude the success of surgical revascularization in improving blood pressure control.3Westenend P.J. Smedts F. de Jong M.C. Lommers E.J. Assmann K.J. A 4-year-old boy with neurofibromatosis and severe renovascular hypertension due to renal arterial dysplasia.Am J Surg Pathol. 1994; 18: 512-516Crossref PubMed Scopus (29) Google Scholar, 18Greene J.F. Fitzwater J.E. Burgess J. Arterial lesions associated with neurofibromatosis.Am J Clin Pathol. 1974; 62: 481-487Crossref PubMed Scopus (237) Google Scholar Medical treatment should be the initial approach to control hypertension to allow maximal body growth before any intervention.2Riccardi V.M. Von Recklinghausen neurofibromatosis.N Engl J Med. 1981; 305: 1617-1627Crossref PubMed Scopus (948) Google Scholar, 16Criado E. Izquierdo L. Lujan S. Puras E. del Mar Espino M. Abdominal aortic coarctation, renovascular hypertension, and neurofibromatosis.Ann Vasc Surg. 2002; 16: 363-367Abstract Full Text PDF PubMed Scopus (36) Google Scholar, 23Stanley J. Fry W. Pediatric renal artery occlusive disease and renovascular hypertension.Arch Surg. 1981; 116: 669-676Crossref PubMed Scopus (93) Google Scholar However, poorly controlled hypertension on medical therapy is undesirable in children because of the progression of end-organ damage.15Guthrie G.P. Tibbs P.A. McAllister R.G. Stevens R.K. Clark D.B. Hypertension and Neurofibromatosis.Hypertension. 1982; 4: 894-897Crossref PubMed Scopus (11) Google Scholar, 16Criado E. Izquierdo L. Lujan S. Puras E. del Mar Espino M. Abdominal aortic coarctation, renovascular hypertension, and neurofibromatosis.Ann Vasc Surg. 2002; 16: 363-367Abstract Full Text PDF PubMed Scopus (36) Google Scholar, 23Stanley J. Fry W. Pediatric renal artery occlusive disease and renovascular hypertension.Arch Surg. 1981; 116: 669-676Crossref PubMed Scopus (93) Google Scholar The reported success of surgical intervention approached an 80% rate of cure or improvement of renovascular hypertension, and a number of reports documented very long-term success.6Nakhoul F. Green J. Angel A. Ofer A. Ben-Izhak O. Lewin M. Renovascular hypertension associated with neurofibromatosis Two cases and review of the literature.Clin Nephrol. 2001; 55: 322-326PubMed Google Scholar, 8McTaggart S. Gelati S. Walker R.G. Powell H.R. Jones C.L. Evaluation and long-term outcome of pediatric renovascular hypertension.Pediatr Nephrol. 2000; 14: 1022-1029Crossref PubMed Scopus (69) Google Scholar, 9Estepa R. Gallego N. Orte L. Puras E. Aracil E. Ortuno J. Renovascular hypertension in children.Scand J Urol Nephrol. 2001; 35: 388-392Crossref PubMed Scopus (50) Google Scholar, 16Criado E. Izquierdo L. Lujan S. Puras E. del Mar Espino M. Abdominal aortic coarctation, renovascular hypertension, and neurofibromatosis.Ann Vasc Surg. 2002; 16: 363-367Abstract Full Text PDF PubMed Scopus (36) Google Scholar, 23Stanley J. Fry W. Pediatric renal artery occlusive disease and renovascular hypertension.Arch Surg. 1981; 116: 669-676Crossref PubMed Scopus (93) Google Scholar, 24Millan V.G. McCauley J. Kopelman R.I. Madias N.E. Percutaneous transluminal renal angioplasty in nonatherosclerotic renovascular hypertension.Hypertension. 1985; 7: 668-674Crossref PubMed Scopus (38) Google Scholar Percutaneous transluminal angioplasty has been attempted in these patients, but several studies have suggested disappointing technical results, and the long-term results are not documented.2Riccardi V.M. Von Recklinghausen neurofibromatosis.N Engl J Med. 1981; 305: 1617-1627Crossref PubMed Scopus (948) Google Scholar, 6Nakhoul F. Green J. Angel A. Ofer A. Ben-Izhak O. Lewin M. Renovascular hypertension associated with neurofibromatosis Two cases and review of the literature.Clin Nephrol. 2001; 55: 322-326PubMed Google Scholar, 8McTaggart S. Gelati S. Walker R.G. Powell H.R. Jones C.L. Evaluation and long-term outcome of pediatric renovascular hypertension.Pediatr Nephrol. 2000; 14: 1022-1029Crossref PubMed Scopus (69) Google Scholar, 16Criado E. Izquierdo L. Lujan S. Puras E. del Mar Espino M. Abdominal aortic coarctation, renovascular hypertension, and neurofibromatosis.Ann Vasc Surg. 2002; 16: 363-367Abstract Full Text PDF PubMed Scopus (36) Google Scholar, 23Stanley J. Fry W. Pediatric renal artery occlusive disease and renovascular hypertension.Arch Surg. 1981; 116: 669-676Crossref PubMed Scopus (93) Google Scholar, 24Millan V.G. McCauley J. Kopelman R.I. Madias N.E. Percutaneous transluminal renal angioplasty in nonatherosclerotic renovascular hypertension.Hypertension. 1985; 7: 668-674Crossref PubMed Scopus (38) Google Scholar, 25Mallmann R. Roth F.J. Treatment of neurofibromatosis associated renal artery stenosis with hypertension by percutaneous transluminal angioplasty.Clin Exper Theory Practice. 1986; A8: 893-899Crossref Scopus (12) Google Scholar, 26Gardiner G.A. Freedman A.M. Shlansky-Goldberg R. percutaneous transluminal angioplasty delayed response in neurofibromatosis.Radiology. 1988; (Oct): 79-80PubMed Google Scholar Reconstruction of these complex renal lesions often requires ex-vivo repair with autotransplantation in the iliac fossa.27Kyriakides G.K. Najarian J.S. Renovascular hypertension in childhood successful treatment by renal autotransplantation.Surgery. 1979; 85: 611-616PubMed Google Scholar In our patient, multiple stenotic areas of the renal artery with aneurysms of the distal artery and involvement of segmental branches made ex-vivo reconstruction necessary. The success rate of autotransplantation for renovascular hypertension has been reported to be about 97%,27Kyriakides G.K. Najarian J.S. Renovascular hypertension in childhood successful treatment by renal autotransplantation.Surgery. 1979; 85: 611-616PubMed Google Scholar and this technique has led to the treatment of renal vascular lesions that otherwise might have required nephrectomy. Despite all technical options, in some cases a primary nephrectomy should be considered when surgery is indicated and vascular reconstruction is not technically possible. In summary, patients with neurofibromatosis and hypertension should be screened for pheochromocytoma and renovascular hypertension. In the presence of renal artery stenosis, children with sustained hypertension despite optimal medical management should undergo intervention. The preferred treatment for renovascular hypertension in children with neurofibromatosis remains surgical, and an ex-vivo reconstruction will be required in many cases. The characteristic vascular lesions in neurofibromatosis consist of stenotic, proliferative nodules of spindle cells with a marked increased in the mucoid matrix, and thinning and loss of media and elastic lamina that lead to aneurysm formation. Diffuse involvement of intraparenchymal arteries may preclude complete resolution of hypertension with treatment of more proximal stenotic lesions. Although the goal of treatment should be control of hypertension and renal salvage, nephrectomy may be required when revascularization is impossible or when hypertension persists or worsens after intervention. We thank Dr Frederick Miller for assistance with the histologic review of the case and Dr Jonathan Cohen for editorial advice.