Moyamoya disease associated with renovascular disease in a young African-Brazilian patient

Moyamoya is a rare disease characterized by fibrous dysplasia of the internal carotid and proximal cerebral arteries, which has been described mainly in young Japanese. We present a case of Moyamoya disease with renal artery involvement in a young male patient with an African origin. A 15-year-old boy was referred to our hospital due to uncontrolled blood pressure, headache, somnolence, cognitive deficit and multiple lacunar infarcts in the computed tomography. Cerebral arteriography showed the absence of the normal vascular anatomy at the level of the circle of Willis. The intracranial vessels presented severe stenosis or were occluded and replaced by an extensive network of ectasic collateral vessels. Abdominal ultrasound examination identified asymmetric kidneys, and renal arteriography showed a tight stenosis of the ostium and proximal segment of right main artery, which was only partially relieved by balloon angioplasty. A saphenous bypass from aorta to the right renal artery re-established the renal blood flow. Blood pressure dropped after surgery and was controlled with low doses of diuretic and beta-blocker. After arteriography he presented right hemiplegia, with partial recovering in the following months. In conclusion, we described the first case of Moyamoya disease with concomitant renovascular disease in a young adult of African origin, an association that may be more frequent than usually suspected in clinical practice.