|Downtime form:||A-1a Doctor/Provider Orders - Pathology Core and Specialty Care Nursery|
Abstain from medications for 72 hours prior to collection.
Absolute Minimum: 2.5 mL of a well-mixed urine from 24 hour collection. Random urine is also accepted at reference lab. Refrigerate during collection and submission.
Components Reference Interval Metanephrine Male 0-6 years Not Established 7-12 years 45-179 μg/d 13-17 years 61-202 μg/d 18 years and older 62-207 μg/d Female 0-6 years Not Established 7-17 years 42-135 μg/d 18 years and older 39-143 μg/d Normetanephrine Male 0-6 years Not Established 7-12 years 70-273 μg/d 13-17 years 92-312 μg/d 18-29 years 95-379 μg/d 30 years and older 125-510 μg/d Female 0-6 years Not Established 7-12 years 52-247 μg/d 13-17 years 73-266 μg/d 18 years and older 109-393 μg/d Creatinine (24 hr) Male 3-8 years 140-700 mg/d 9-12 years 300-1300 mg/d 13-17 years 500-2300 mg/d 18-50 years 1000-2500 mg/d 51-80 years 800-2100 mg/d 81 years and older 600-2000 mg/d Female 3-8 years 140-700 mg/d 9-12 years 300-1300 mg/d 13-17 years 400-1600 mg/d 18-50 years 700-1600 mg/d 51-80 years 500-1400 mg/d 81 years and older 400-1300 mg/d
Smaller increases in metanephrine and/or normetanephrine concentrations (less than two times the upper reference limit) usually are the result of physiological stimuli, drugs, or improper specimen collection. Essential hypertension is often associated with slight elevations (metanephrine less than 700 μg/d and normetanephrine less than 900 μg/d). Elevated concentrations may be due to intense physical activity, life-threatening illness, and drug interferences.
Significant elevation of one or both metanephrines (three or more times the upper reference limit) is associated with an increased probability of a neuroendocrine tumor.
Secreting neuroendocrine tumors typically are associated with metanephrine or normetanephrine concentrations several times higher than the upper reference intervals. Other reasons for elevated concentrations include intense physical activity, life-threatening illness, and drug interferences. Essential hypertension is often associated with slight elevations (metanephrine less than 3500 nmol/day and normetanephrine less than 4900 nmol/day). Other reasons for slight and moderate elevations include emotional and physical stress and improper specimen collection.
Urine Tests Requiring Preservatives, Refrigeration or Special Containers