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Stroke in young patients with hyperhomocysteinemia due to cystathionine beta-synthase deficiency

P J Kelly1, K L Furie, J P Kistler

  • 1Stroke Service, Department of Neurology, VBK 802, Massachusetts General Hospital, Fruit St., Boston, MA 02114, USA. pikelly@partners.org

Neurology
|January 29, 2003
PubMed

Insights

Severe hyperhomocysteinemia (Hyper-Hcy), linked to cystathionine beta-synthase (CBS) deficiency, can cause stroke in young adults through artery-to-artery embolism and dissection. Screening for Hyper-Hcy is recommended in young stroke patients.

Area of Science:

  • Neurology
  • Genetics
  • Biochemistry

Background:

  • Hyperhomocysteinemia (Hyper-Hcy) is a known risk factor for atherosclerosis and venous thrombosis.
  • The specific mechanisms linking Hyper-Hcy to stroke remain unclear.

Observation:

  • Three unrelated patients with premature stroke and severe Hyper-Hcy due to cystathionine beta-synthase (CBS) deficiency were studied.
  • Two patients initially presented with embolic cerebral and retinal infarction without a prior diagnosis of homocystinuria.
  • Family screening identified additional members with clinically silent homocystinuria and severe Hyper-Hcy.

Findings:

  • Mechanisms of cerebrovascular disease included carotid intraluminal thrombosis, arterial dissection, and possible cardiac embolism.
  • Affected individuals exhibited mild phenotypes, lacking classic CBS deficiency signs, but had elevated plasma and urine homocysteine (Hcy) and methionine.
  • Genotyping revealed heterozygous CBS mutations (I278T, D444N, G307S) in affected individuals.

Implications:

  • Artery-to-artery embolism and dissection are potential causes of stroke in young adults with homocystinuria.
  • These findings support screening for Hyper-Hcy in young adults experiencing stroke, even without classic homocystinuria phenotypes.
  • Early detection and management of Hyper-Hcy may prevent recurrent cerebrovascular events.
Abstract

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