The catecholamines belong to the so-called sympathomimetics. These are transmitter substances (transmitters) that act in the autonomic nervous system (sympathetic nervous system), where they mediate a variety of tasks such as vasoconstriction (vasoconstriction) or broncholysis (bronchial dilation). The catecholamines can also be used in the diagnosis of various tumor diseases as so-called tumor markers.Tumor markers are endogenous substances that are produced by tumors and can be detected in the blood. They can provide an indication of a malignant (malignant) neoplasm and are used as a follow-up test in cancer follow-up.The catecholamines are not specific for a tumor.
The procedure
Material needed
- 24h collection urine with exact collection amount→ add hydrochloric acid before starting.
Preparation of the patient
- The following foods should be avoided for 3 days before and during collection:
- Fruits such as bananas
- Nuts and almonds, vanilla
- Coffee, tea
- Cheese
- The following medications may affect the results, so they should be discontinued approximately 1 week before the start of the collection period, if possible:
- Antibiotics such as tetracyclines or sulfonamides.
- Antihypertensives (blood pressure medications) such as alpha-methyldopa, beta-blockers, clonidine, guanethidine, reserpine
- Insulin
- Sedatives (tranquilizers) such as barbiturates
- Other agents such as chlorpromazine,caffeine, salicylates, vitamin B.
Interfering factors
- See preparation of the patient
Normal values catecholamines
| Catecholamine/metabolite | Adult(μg/d) | Children(μg/d) |
| Free catecholamines | < 140 | <6TH LY: < 406TH-10TH LY: < 70 |
| Adrenaline | < 20 | Infants <2.51.-2nd LY: <3.52.-4th LY: <6.04.-7th LY: <10.07.-10th LY: <14.0 |
| Norepinephrine | 23-105 | Infants: <10.01.-2nd LY: <17.02.-4th LY: <29.04.-7th LY: <45.07.-10th LY: <65.0 |
| Dopamine | < 620 | Infants: < 85.01.-2nd LY: < 140.02.-4th LY: < 260.04.-18th LY: < 450.0 |
| Metanephrine | < 800 | < 6. LJ: < 300> 6. LJ: < 500 |
| Vanillic mandelic acid (VMS) (metabolite) in mg/d. | 3,3-6,5 | Infants: <1.51.-2nd LY: <2.02.-4th LY: <2.54.-10th LY: <5.0 |
| Homovanillic acid (HVS) (metabolite) in mg/d. | < 7,5 | Infants: <1.01.-2nd LY: <4.02.- 10th LY: <6.0 |
Indications
- Suspected catecholamine-producing tumors such as pheochromocytoma/neuroblastoma.
- Episodic or refractory hypertension.
- Therapy/progression control in tumor diseases mentioned above.
Interpretation
Interpretation of increased values
- Catecholamine-producing tumors (usually highly elevated values, occasionally barely elevated or unremarkable values!)
- Pheochromocytoma (detection of vanillinmandelic acid).
- Neuroblastoma (detection of homovanillic acid)(highly elevated dopamine concentrations indicate malignancy).
- Hypoglycemia (hypoglycemia).
- Physical stress
- Cushing’s disease – disease caused by an increased supply of glucocorticoids.
- Myocardial infarction (heart attack).
- Stress
Interpretation of lowered values
- No diagnostic significance
Further notes
- In borderline elevated or only moderately elevated catecholamines, a clonidine inhibition test (clonidine suppression test) may be recommended for further clarification! For this, the systolic blood pressure value must be > 120 mmHg. Procedure: After clonidine administration, the plasma concentration of catecholamine metabolites decreases due to central inhibition of the sympathetic nervous system in healthy subjects. Pathologic findings: with basal levels usually markedly elevated (epinephrine > 85 ng/l, norepinephrine > 275 ng/l), no decrease in plasma norepinephrine/epinephrine levels is observed in pheochromocytoma.
- Determination of free metanephrines in plasma is currently the most sensitive laboratory test for the detection of pheochromocytoma.
