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[Severe hyperhomocysteinemia revealing homocystinuria in two young adults with mild phenotype]

V Ducros1, J Rousset, K Garambois

  • 1Département de biologie intégrée, CHU, Grenoble, France. VDucros@chu-grenoble.fr

La Revue De Medecine Interne
|November 22, 2005
PubMed

Insights

Elevated total plasma homocysteine levels can indicate homocystinuria, a condition often undiagnosed in young adults with venous thromboembolism. Early screening is crucial for timely diagnosis and management.

Area of Science:

  • Biochemistry
  • Genetics
  • Vascular Medicine

Background:

  • Homocystinuria diagnosis is often delayed in young adults presenting with mild phenotypes.
  • Vascular disease investigation frequently involves total plasma homocysteine determination.

Observation:

  • Two young adults, a 26-year-old man and a 22-year-old woman, experienced severe vascular events (cerebral infarction and renal vein thrombosis, respectively).
  • Both patients presented with elevated total plasma homocysteine levels, leading to further amino acid analysis and diagnosis of homocystinuria.
  • Reduced cystathionine beta-synthase activity in skin fibroblasts confirmed the diagnosis.

Findings:

  • High total plasma homocysteine is a key indicator for screening homocystinuria.
  • Amino acid analysis and enzymatic assays are essential for confirming the diagnosis.
  • Venous thromboembolism in young adults can be a presenting sign of undiagnosed homocystinuria.

Implications:

  • Total plasma homocysteine screening should be considered in young adults with unexplained venous thromboembolism.
  • Early diagnosis of homocystinuria can prevent severe vascular complications.
  • This highlights the importance of biochemical screening for metabolic disorders presenting with thrombotic events.
Abstract

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