[Arterial complications of neurofibromatosis]

Type 1 neurofibromatosis (NF1) is the most frequently observed phacomatosis, but involvement of arterial trunks is uncommon. Expression depends on the localization and is not easily related to the causal condition. Seven patients with type 1 neurofibromatosis developed vascular manifestations (table I) disclosed by hypertension (n = 2) digestive angina (n = 1), arterial rupture (n = 1) and aneurysm of the subrenal aorta (n = 1). The diagnosis of NF1 was clear in 5 cases; in 2 cases, the diagnosis could only be established on the basis of pathology findings demonstrating dysplasia of the media with voluminous periadventitial hypertrophic nerves (table II). All the large arteries can be involved in NF1. A complete vascular work-up is needed to identify multiple arterial localizations as found in two of our cases. Thoraco-abdominal stenosis was observed in 5 cases leading, in 2 cases, to coarctation with a hemodynamic and functional impact requiring aortic revascularization. The most frequently observed localization involves the renal arteries: 3 of our patient had occlusive lesions of the renal arteries and in 2, aneurysms were observed. Three of our patients (including 2 of the preceding), had major occlusion of digestive arteries. Three other cases revealed an aneurysm of inflammatory subrenal aorta, a rupture of the iliac into the inferior vena cava and a rupture covered by a subclavian aneurysm. The indication for surgery depends on the arterial signs of associated complications (5 of our cases). In one case surgery was indicated to prevent rupture of a splenic artery aneurysm and an aneurysm of the subrenal abdominal aorta. Two cases were treated by exclusion (ilio-cava fistula) or excision (splenic aneurysm); renal or digestive revascularization was performed with arterial or venous autografts in young patients (3 cases). One extensive abdominal coarctation was repaired with a PTFE graft as were the subclavian and subrenal aorta aneurysms. One patient with an ilio-cava fistula died from collapsus. Long-term results of the revascularizations are satisfactory with good control of the hypertension and total regression of the digestive angina. Fibrodysplasia of the renal or digestive media occurring alone or thoraco-abdominal coarctation should suggest NF1 and lead to a complete work-up to identify other arterial localizations. Patients should be followed regularly to prevent complications which in case of rupture can be life-threatening.