Test Directory

• Urinary epinephrine
• Urinary norepinephrine
• Urinary dopamine

Work up neuroblastoma; diagnose pheochromocytoma. Pheochromocytomas and occasional paragangliomas may cause persistent or paroxysmal hypertension. Work up palpitation, severe headache, diaphoresis. Urine collections are preferred to blood sampling when there is suspicion for tumor (e.g., family history of MEA II) when hypertension is not paroxysmal. Evaluate for possible multiple endocrine adenomatosis type II.

Specimen Type: 24 Hour Urine

Collection Container: 24 Hour Plastic Urine Container

Desired Specimen Volume: 30 mL

1. Collect 24-hour urine in a timed collection kit.
2. Specimen must be collected in a plastic container and refrigerated during collection.

1. Mix well and transfer 30 mL of urine to clear aliquot tubes (screw caps) or transfer to a sterile container (screw cap).
2. Adjust pH of specimen to <5 by using 6N HCl.

Avoid patient stress. Many drugs (reserpine and α-methyldopa, levodopa, monoamine oxidase inhibitors, and sympathomimetic amines) may interfere and should be discontinued two weeks prior to specimen collection. Nose drops, sinus and cough medicines, bronchodilators and appetite suppressants, α2-agonists, calcium channel blockers, converting enzyme inhibitors, bromocriptine, phenothiazine, tricyclic antidepressants, α- and β-blockers, and labetalol may interfere. Mandelamine® interferes, but thiazides do not. Caffeine products should be avoided before and during collection. The patient should not be subjected to hypoglycemia or exertion. Increased intracranial pressure and clonidine withdrawal can cause false-positive results.

Transport to the laboratory refrigerated. 

• Specimen with no preservative
• Original container with pH >5

 See patient report.

False-negatives and false-positives occur. Urine collections for metanephrines are among the best tests for pheochromocytoma. Sheps et al use urinary catecholamine fractionation as confirmation, following a metanephrine test. Neuroblastoma is better worked up with urinary collections for HVA and VMA. MHPG (3-methoxy-4-hydroxyphenylethylene glycol) is a major metabolite of norepinephrine in the central nervous system; it is a metabolite of some neuroblastomas.

• Dopamine, 24-Hour Urine
• Epinephrine, 24-Hour Urine
• Fractionation, Urinary Free Catecholamines
• Free Catecholamine Fractionation
• Norepinephrine, 24-Hour Urine