|Values are valid only on day of printing.|
First preferred test for screening for catecholamine-secreting tumors in a random urine specimen when requesting both homovanillic acid and vanillylmandelic acid
Supporting a diagnosis of neuroblastoma
Monitoring patients with a treated neuroblastoma
Homovanillic acid (HVA) and vanillylmandelic acid (VMA) measurements in urine are used for screening children for catecholamine-secreting tumors such as neuroblastoma, pheochromocytoma, and other neural crest tumors and monitoring those who have had treatment for these tumors.
HVA measurement is also useful to diagnose children with disorders of catecholamine metabolism such as monamine oxidase-A deficiency, which results in decreased urinary HVA values, and dopamine beta-hydroxylase deficiency, which results in elevated urinary HVA values.
VMA is not the analyte of choice for diagnosis of pheochromocytoma, which is better detected by testing for metanephrines.
Treatment with L-dopa can impact test results and should be discontinued 24 hours prior to collection. Bactrim can impact test results and should be noted at time of collection.
Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)