Fibromuscular dysplasia with moyamoya phenomenon in a patient with Alport's syndrome.: A type IV collagen disorder

Introduction. Alport's syndrome is a hereditary progressive nephropathy associated with neurosensorial deafness, secondary to mutations of the genes which codify the a chains of collagen IV. In the literature we have found isolated reports of cases with nervous system involvement. Clinical case. A 37 year old woman was diagnosed as having Alport's syndrome with terminal secondary chronic renal failure and bilateral neurosensorial deafness. She was assessed following repeated transient ischemic attacks of the left hemisphere over the previous three years. Neurological examination was normal. Magnetic resonance showed an ischemic stroke of the left frontal white matter, and on arteriography there was tubular stenosis of the left extracranial internal carotid artery and proximal occlusion of the homolateral anterior and medial cerebral arteries with a compensatory deep vascular network, compatible with fibromuscular dysplasia and secondary moyamoya phenomenon. Conclusions. Although the association between fibromuscular dysplasia and Alport's syndrome may be casual, we suggest that there may be a common mechanism of pathogenesis in both syndromes, related to the expression of type IV collagen in the vascular basal membranes.