Urinalysis is a very important and informative method for diagnosing all kinds of diseases. Sometimes there is a need for this study to detect methanephrine levels. An increase in it in the patient’s urine may indicate the development of dangerous pathological processes. What is methanephrine and what does the deviation of its level from the norm indicate, we will consider in the article.
Definition
Metanephrine and normetanephrine are intermediate breakdown products of catecholamine hormones - adrenaline and norepinephrine, which are of great importance in adapting the body to stressful situations. Having fulfilled their functions, these hormones naturally break down and are excreted in the urine within 24 hours. For this reason, a slight urinary methanephrine content, as well as a slight increase under stress, is normal. A significant or long-term increase in this indicator may indicate the development of neuroendocrine tumors, in which stress hormones are produced in an increased volume, as a result of which an increase in the volume of their decay products in urine is observed. It is necessary to carry out additional diagnostic measures.
Norms
Below is a table of normal values.
| Age | Metanephrine, mcg / day | Normetanephrine, mcg / day |
| from 0 to 3 months | 5.9—37 | 46-156 |
| from 3 to 6 months | 6.1–42 | 31-111 |
| from 6 to 9 months | 12–41 | 42-109 |
| from 9 to 12 months | 8.5-101 | 23-103 |
| from 1 to 2 years | 6.7-52 | 32-118 |
| from 2 to 6 years | 11-100 | 50-111 |
| from 6 to 10 years | 54-136 | 47-175 |
| from 10 to 16 years | 39-243 | 52-290 |
| Adults | 0-320 | 0-390 |
Norms do not depend on gender, but significantly differ in age.
Normal values may vary by laboratory. In this regard, re-analysis is recommended to be carried out in the same clinic as the previous time.
When to take an analysis
There are a number of signs, upon detection of which it is necessary to contact a medical institution as soon as possible and pass an analysis for the detection of methanephrins and normetanephrins in the urine. These symptoms include:
- Long-term elevated blood pressure, which is difficult to normalize.
- Heart rhythm disturbances.
- A steady increase in body temperature (may be slight).
- Dry mouth.
- Nausea.
- Dizziness, sleep disturbance, weakness.
- Weight loss without loss of appetite.
- Increased sweating even at rest.
- Headache.
- Panic attacks.
- Fainting or fainting.
- Nervousness, excitability, mood swings.
- Jumps in glucose levels (regardless of diabetes).
Urine tests for methanephrine and normetanephrine are also prescribed for suspected neuroendocrine malignancies.
The direction for analysis in most cases is issued by a therapist, oncologist, surgeon or endocrinologist.
Preparation
In the analysis of daily urine for methanephrine, careful preparation is very important, since these indicators are very sensitive to the influence of external circumstances. Consider the basic rules recommended for implementation before collection:
- First of all, a few days before the analysis, you should refuse to take certain categories of drugs. These include some antibiotics, tranquilizers, adrenergic blockers, vasoconstrictor drugs, and others.
- For 4 hours do not smoke.
- 2 days before the analysis, exclude the use of coffee, chocolate, alcoholic beverages, eggs, products containing vanillin, avocados, bananas, tomatoes and others.
- Avoid physical exertion.
- Eliminate nervous tension.
Rules for Submission of Analysis
Daily urine is used to detect methanephrine. This will require a large sterile container, which will be collected throughout the day. Before each urination, it is necessary to carry out hygiene procedures.
The first morning urine must be poured, all subsequent urine must be collected in one container. After each filling, the container is placed in a cold place. On the morning of the next day, about 100 ml should be separated from the total volume of collected urine. After this, it is necessary to deliver the sample to the laboratory as soon as possible (no later than four hours later).
Increase values
Increased values of methanephrins in daily urine may indicate the presence of malignant tumors or be the result of an incorrect collection of analysis. The most common reasons for the increase are:
- Stresses, especially prolonged.
- Large physical exertion before analysis.
- Drinking alcohol or smoking before taking urine.
- Taking medications that may affect the result.
But sometimes an increase in values indicates the development of dangerous diseases, which include:
- Tumors of the adrenal gland. In this case, an increased amount of catecholamines is produced. It is worth noting that the analysis will not be able to indicate the size of the tumor or its complications. An additional examination is needed.
- Benign or malignant neuro-tumors (e.g., paragangliomas, neuroblastomas, and ganglioneuromas).
- Hepatitis or cirrhosis.
- An increase in methanephrins and normetanephrins in daily urine can cause heart and vascular diseases (myocardial infarction, angina pectoris, heart failure).
- Pathological conditions that occur in the hypothalamus, which provoke disruptions in the sympathoadrenal system.
- Acute peptic ulcer of the duodenum or stomach.
- Hypertension, manifested in acute form.
There are situations in which a false positive result is diagnosed. It is necessary to consult a doctor and undergo additional tests to confirm or exclude dangerous pathologies. For example, an analysis can be assigned to the level of catecholamines themselves in the urine, as well as the final products of their metabolism.
A constant increase in normetanephrine indicates the development of pathological conditions that arise in the hypothalamus or in the internal organs.
In the event that an increase in methanephrine and normetanephrine is detected after undergoing treatment for tumor processes that occur in the body, this may be evidence of poor treatment or the development of a relapse of the disease. You need to see a doctor faster.
Lower values
Decreased urine methanephrine may indicate diseases such as:
- Leukemia.
- Chronic and acute inflammatory processes that occur in the body.
- Addison's disease.
- Connective tissue diseases.
It is worth noting that a decrease in performance is quite rare and may be the result of improper urine collection or the use of an unsterile container.
Additional diagnostics
If deviations from normal values of the level of methanephrine and normetanephrine are detected, the doctor prescribes a set of additional diagnostic measures to clarify the diagnosis, which include the following studies:
- General blood analysis.
- ECG.
- EEG.
- Blood chemistry.
- Ultrasound examination of the adrenal gland, abdominal cavity and other organs.
- Endoscopy
- Adrenal MRI to determine their condition.
- Computed tomography and others.
Also, a urinalysis for a change in the level of methanephrine and normetanephrine is necessarily repeated.
Conclusion
Each person needs to carefully monitor their health as closely as possible, and at the first suspicious signs, you should rather consult a doctor who will determine a number of necessary diagnostic measures. Timely diagnosis will allow you to identify dangerous diseases at an early stage, which will help to prescribe effective therapy, because some pathological conditions that occur in the body, without timely treatment, can be a threat to human life and health.
Urinalysis for methanephrine level is recommended to be entered into a systematic examination mode, since this indicator allows you to identify many life-threatening diseases. But you need to remember the rules for preparing for the analysis and its implementation, because if the urine is collected incorrectly, you can get a false result.