Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (987 page)

Kluijtmans LA, Young IS, Boreham CA, et al. Genetic and nutritional factors contributing to hyperhomocysteinemia in young adults.
Blood.
2003;101:2483–2488.

Refsum H, Smith AD, Ueland PM, et al. Facts and recommendations about total homocysteine determinations: An expert opinion.
Clin Chem.
2004;50:3–32.

Wierzbodi AS. Homocysteine and cardiovascular disease: A review of the evidence.
Diab Vasc Dis.
2007;4:143–149.

HOMOVANILLIC ACID, URINE (HVA)

   Definition

   HVA is the main terminal metabolite of catecholamine neurotransmitter, dopamine. For the diagnosis of neuroblastoma, it is important to carry out simultaneous determinations of HVA and VMA because either or both elevated.

   
Normal range:
0.0–15.0 mg/day.

   Use

   Assist in the diagnosis of pheochromocytoma, neuroblastoma, and ganglioblastoma

   Monitor the course of therapy

   Screening for catecholamine-secreting tumors in children when accompanied by VMA

   Evaluating patients with possible inborn errors of catecholamine metabolism

   Interpretation

Increased In

   Neuroblastoma

   Pheochromocytoma

   Paraganglioma

   Riley-Day syndrome