Rare case of 18-month-old child with Moyamoya disease presenting with tubular dysfunction

A new finding in Moyamoya disease reported the occurrence of hypertension preceded by tubular dysfunction with an atypical hyponatremic-hypertensive syndrome (HHS). unilateral renal artery stenosis accounts for 8%-10% of renovascular hypertension in childhood and rarely causes hyponatremic-hypertensive syndrome (HHS).

Moyamoya disease is a progressive steno-occlusive cerebrovascular arteriopathy of unknown origin involving the distal intracranial internal carotid artery and its main branches and is a rare cause of pediatric stroke. It exhibits a distinguishing feature of the presence of a collateral network of overgrown and dilated small arteries from the circle of Willis that appear as a puff of smoke and hence the name Moyamoya. Different angiographic images are seen in certain disease conditions where such patients are characterized as Moyamoya syndrome.  Majority of the pediatric cases present clinically as ischemic stroke, while some as transient ischemia and hemorrhagic stroke with hemiparesis. Sometimes intracranial bleeding is seen in some adult patients, but children have more epilepsy than adults. Extracranial sites like the carotid, pulmonary, coronary, and renal arteries also show steno-occlusive arterial changes. 

Maria Luisa Conte et al presented a case of an atypical Moyamoya disease in the journal BMC Pediatrics. A18-month-old boy with a recent history of polyuria and polydipsia, having acute febrile gastroenteritis with neurological impairment, severe dehydration, hyponatremia, hypokalemia, kidney tubular dysfunction, and elevated aldosterone and renin even with normal blood pressure. Fluid and electrolyte levels were corrected, and the boy recovered completely.