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Test ID: Normetanephrine (24h urine)
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Normetanephrine (24h urine)
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Normetanephrine (24h urine)
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Useful For
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The investigation of hypertension, specifically for phaeochromocytoma
In paediatric patients, the measurement of normetanephrine can be useful for the investigation of neuroblastomas.
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Method name and description
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High performance liquid chromatography coupled to electrochemical detection.
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Clinical information
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Urine normetanephrine is measured in a metanephrines panel that includes metanephrine. Together, the urine metanephrines are typically used in the investigation of phaechromocytomas and paragangliomas. Phaeochromocytomas and paraganagliomas are rare neuroendocrine tumours characterised by the overproduction of catecholamines. The catecholamines are then o-methylated to form the metanephrines. Often, patients present with classical symptoms of episodic headache, sweating and tachycardia.
In paediatric patients the measurement of urine metanephrines can be useful in the diagnosis and monitoring of neuroblastomas.
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Specimen type / Specimen volume / Specimen container
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Specimen type: urine, 24 hours collection.
Specimen volume: total urine volume collected in 24 hours.
Specimen container: suitable 24 hours plain urine collection container/s.
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Collection instructions / Special Precautions / Timing of collection
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Patient should not be under pressure or actions requiring great effort.
Patient should avoid the following foods and drinks for 48 hours before urine specimen collection:
Pineapple.
Banana.
Plums.
Tomatoes.
Walnuts.
Chocolate.
Vanilla.
Coffee.
Tea.
Soft drinks.
Spices as possible and absolutely to avoid Curry.
Patient should avoid smoking cigarettes during specimen collection.
Paracetamol can interact with assays and that cough medicines may contain sympathomimetic.
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Relevant clinical information to be provided
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Presenting clinical signs and symptoms
Relevant medications
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Storage and transport instructions
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Transport Temperature: 2 - 30 °C.
Storage Temperature: -18°C after add the preservative until processing.
The sample should not be thawed till analysis.
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Specimen Rejection Criteria
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Insufficient specimen quantity.
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Biological reference intervals and clinical decision values
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Age
Years
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Male
µmol/24h
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Female
µmol/24h
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3 - 8
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0.2 - 0.9
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0.2 - 0.8
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9 - 12
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0.5 - 2.3
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0.3 - 1.5
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13 - 17
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0.5 – 2.5
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0.3 -1.6
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18 - 40
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0 - 3.6
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0 - 3.0
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40 - 60
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0 - 4.3
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0 - 3.5
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> 60
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0 - 4.5
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0 - 3.7
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Factors affecting test performance and result interpretation
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Antihypertensive medications, acute stress, acute illness, obstructive sleep apnoea can all cause increases in urine metanephrine excretion.
In addition, certain medications and dietary components can cause analytical interferences. A notable example is capsaicin-containing foods (peppers, chillis) that are often used in the preparation of spicy meals.
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Turnaround time / Days and times test performed / Specimen retention time
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Turnaround time: 5 working days.
Days and times test performed: Once a week.
Specimen retention time: 30 days.
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