Use for patients where 24-hour urine collection is difficult (eg, pediatric patients), as a 24-hour urine collection is preferable.
Patient should avoid salicylates, caffeine, phenothiazine, and antihypertension agents, as well as coffee, tea, chocolate, fruit (especially bananas and any vanilla-containing substances) for 72 hours prior to collection.
Transfer 10mL random urine to a Transfer vial/tube with cap - 12mL (LabCorp)
Ambient (preferred) - 7 days
Refrigerated - 14 days
Frozen - 14 days
Freeze/thaw cycles - stable x3
Liquid chromatography/tandem mass spectrometry (LC/MS-MS)
< 2 years: 0.0−18.8 mg/g creatinine
2 - 4 years: 0.0−11.0 mg/g creatinine
5 - 9 years: 0.0−8.3 mg/g creatinine
10 - 19 years: 0.0−8.2 mg/g creatinine
> 19 years: 0.0−6.0 mg/g creatinine
Pediatric testing for the evaluation of hypertension; diagnose and follow up neuroblastoma, ganglioneuroma, and ganglioneuroblastoma. Most neuroblastoma patients excrete excess HVA in 24-hour collections. If VMA and HVA are both used in work-up, up to 80% of all cases will be detected.
Some neuroblastoma patients are positive for urinary homovanillic acid abnormality but do not excrete increased VMA. Twenty percent to 32% of patients with neuroblastoma do not have elevation of VMA. Many will have other laboratory abnormalities such as increased metanephrines, homovanillic acid (HVA), or dopamine.