Use

Vanillylmandelic acid (VMA) and other catecholamine metabolites, such as homovanillic acid (HVA) and dopamine, are typically elevated in patients with catecholamine-secreting tumors (eg, neuroblastoma, pheochromocytoma, and other neural crest tumors). More than 90% of individuals with neuroblastoma have elevated VMA and/or HVA. This test is useful for screening children for catecholamine-secreting tumors when requesting testing for VMA only, supporting diagnosis of neuroblastoma, and monitoring treated neuroblastoma patients. VMA is not preferred for detection of pheochromocytoma; metanephrines are better detected via specific tests. Treatment with L‑dopa may impact test results and should be discontinued 24 hours prior to collection. Bactrim may also interfere and should be noted at time of collection.