Treat the Child, Not the Number

Moyamoya is an angiographic description of the ‘puff of smoke’ basal collaterals visualised in typically bilateral, progressive and steno-occlusive arteriopathy of the terminal internal carotid artery and proximal branches. Aetiology is poorly understood however genetic susceptibility and many co-morbid associations are described. Childhood sequelae include transient ischaemic attacks and arterial ischaemic stroke (AIS). Blood pressure (BP) elevation is common but underappreciated and may be secondary to renovascular disease in a proportion. It is also an essential, central response to maintain cerebral perfusion hence key to management is careful BP control. We report an 8-year-old boy with type 1 diabetes who received amlodipine for hypertension of unknown cause. With subsequent diagnosis of moyamoya and previous silent infarction, clinical AIS ensued. This case highlights how reflex antihypertensive agent use may precipitate AIS in moyamoya and that a target BP range with treatment thresholds should be agreed between neurology and nephrology teams.