Caucasian familial moyamoya syndrome with rare multisystemic malformations

Clinical Characteristics of Moyamoya Angiopathy in a Pediatric Cohort

Moyamoya angiopathy is a rare cerebral vasculopathy characterized by a progressive stenosis of the terminal portion of the internal carotid arteries and the development of abnormal collateral vessels. Children with moyamoya angiopathy become symptomatic because of cerebral ischemic complications, and many patients eventually need revascularization. In most pediatric patients with this disease, the etiology is likely genetic. We aim to report clinical characteristics of a single-center cohort of pediatric patients with moyamoya. We performed a retrospective chart review of patients <18 years with angiographically confirmed moyamoya disease evaluated at our institution. An in-house text search tool, Advanced Cohort Explorer, was used to filter electronic medical records for patients with a diagnosis of moyamoya angiopathy from January 1999 to December 2018. The inclusion criteria were age <18 years at the time of onset of disease and a diagnosis confirmed at Mayo clinic. Fifty-one patients met the inclusion criteria. Fifty-five percent of our cohort were male, and the median age was 9 years. Three patients had a family history of moyamoya disease. Approximately half of our patients had bilateral disease. Sixteen patients had a genetic or chromosomal diagnosis (Down syndrome and NF1 being most common). Congenital anomalies like heart defects and renal dysplasia were also noted. This study is unique in that it was a large study on pediatric patients with moyamoya angiopathy. It also highlights the importance of considering genetic syndromes as an underlying cause when moyamoya angiopathy starts early in life.

Neurovascular manifestations of connective-tissue diseases: A review

Patients with connective tissue diseases are thought to be at a higher risk for a number of cerebrovascular diseases such as intracranial aneurysms, dissections, and acute ischemic strokes. In this report, we aim to understand the prevalence and occurrences of such neurovascular manifestations in four heritable connective tissue disorders: Marfan syndrome, Ehlers-Danlos syndrome, Neurofibromatosis Type 1, and Loeys-Dietz syndrome. We discuss the fact that although there are various case studies reporting neurovascular findings in these connective tissue diseases, there is a general lack of case-control and prospective studies investigating the true prevalence of these findings in these patient populations. Furthermore, the differences observed in the manifestations and histology of such disease pathologies encourages future multi-center registries and studies in better characterizing the pathophysiology, prevalence, and ideal treatment options of neurovascular lesions in patents with connective tissue diseases.

Familial moyamoya disease in two Turkish siblings with same polymorphism in RNF213 gene but different clinical features

BACKGROUND

Moyamoya disease is an uncommon, progressive, and occlusive cerebrovascular disorder, predominantly affecting the terminal segment of the internal carotid arteries and its main branches. This occlusion results at the formation of a compensatory collateral arterial network (moyamoya vessels) developing at the base of the brain. The c.14576G>A variant in ring finger protein 213 (RNF213) was recently reported as a susceptibility gene for moyamoya disease.

METHODS

We describe two Turkish pediatric siblings with moyamoya disease born to consanguineous, unaffected Turkish parents.

RESULTS

The first patient (proband) is a 2-year-old boy who presented with afebrile focal seizures, moderate psychomotor retardation, paresis in the left upper and lower extremity, multiple infarctions of the brain, stenosis of the bilateral internal carotid artery and the middle cerebral artery, and stenosis of the right posterior cerebral artery. The second patient is a 10-year-old girl who is an elder sister of proband. She showed normal psychomotor development, millimetric signal enhancement without diffusion limitation of the brain, and stenosis of the bilateral internal carotid artery.

CONCLUSION

We herein report pediatric sibling patients of moyamoya disease who have homozygous wild-type c.14576G>A variant in RNF213, showing different clinical course and disease severity. This is the first report of pediatric siblings with moyamoya disease from Turkey validating the genetic background of most frequent variant in East Asian patients with moyamoya disease.