Since the symptoms of pheochromocytoma are very diverse and rarely manifest in full, this disease can successfully mask more than 100 other diseases, among which there will also be those who, like the hormone swelling, will increase the amount of catecholamines. In connection with such features of pheochromocytoma, the diagnosis of this disease is largely considered a difficult task, therefore laboratory tests are prescribed to confirm the preliminary diagnosis.
The diagnosis of pheochromocytoma should first of all be sent:
- Children with hypertension;
- People with hypertension and frequent crises with unsuccessful standard antihypertensive treatment;
- People with high blood pressure caused by ganglion blockers or β-blockers;
- Patients with fever of uncertain etiology;
- People whose immediate relatives had a tumor of the adrenal gland;
- Patients with a high level of catecholamines, changing electrocardiograms;
- And those who have a tumor with an instrumental examination of the adrenal glands.
Laboratory diagnostics of pheochromocytoma
Pheochromocytoma assays are aimed at the detection of catecholamines and their decay products in plasma and urine. Usually for this purpose in daily urine try to determine the content of normetanephrine and metanephrine, which would indicate an increased production of noradrenaline and adrenaline by the adrenal glands. This method of laboratory diagnosis is indicative in more than 95% of cases. It is also possible to determine pheochromocytoma from the analysis of urine by taking the patient's analysis immediately after the crisis, when the concentration of metomorfins is very high. When diagnosing the disease, it is important during the collection of anamnesis in the patient, to make sure that the patient does not take sympathomimetics, benzodiazepines and chlorpromazine, which can give a false positive result.
As an additional test, for the presence of a hormonal adrenal tumor, take a sample for vanillylmandelic acid, but this sample is not as reliable as the previous one, because under the influence of many foods and medicines it can give both false positive and false negative results.
If the patient has hypertension above 160/110 mm Hg. You can apply a trial with tropaphene or phentolamine, which is injected intravenously and expects fluctuations of blood pressure by 40/25 mm in the first 5 minutes after the test. Having received the expected fluctuation of pressure, one can safely assert about pheochromocytoma, but to carry out such a test in people with normal pressure is dangerous for their health.
After determining the presence of a tumor of the adrenal glands with the help of laboratory and physical research methods, it remains to visualize the tumor, determining its size and location. For this use:
- MRI;
- CT;
- ultrasound.
The first two of these methods are the most revealing, ultrasound often does not show a neoplasm in the kidneys, if the tumor size does not exceed 2 mm. If it is suspected that the pheochromocytoma is malignant, additional bone scanning and lung x-rays are performed to exclude metastases. CT and MRI of the retroperitoneal space, pelvis and abdominal cavity in 95% of cases allows to diagnose neoplasm, since 97% of all tumors are below the diaphragm, and 90% of them are located inside the adrenal glands. If more accurate X-ray diagnostic data are required for diagnosis, bolus contrast is used.
Instrumental diagnosis of pheochromocytoma is necessary to confirm suspicions of adrenal neoplasm, but even based on symptoms and what hormones are thrown into the blood in excess, an experienced physician can determine whether a tumor is in the adrenal gland or near it.
US pheochromocytoma
Ultrasound examination( ultrasound) is one of the instrumental methods for diagnosing pheochromocytoma. When carrying out studies of the organs of the abdominal cavity, the necessary sensitivity of the apparatus is 96-98%.On ultrasound, the tumor is defined as a round or oval formation without a pronounced capsule, which has a non-uniform structure( necrosis, fluid areas, hemorrhages, calcifications) and clear contours. It is characterized by vascularization, as well as one- or two-sided arrangement. When a tumor passes into a malignant form, a metastatic lesion takes place.
Differential diagnosis with symptoms of pheochromocytoma
Manifestations of pheochromocytoma are diverse. When conducting differential diagnosis, you have to analyze a number of symptoms and exclude many pathologies and diseases. More often, the tumor has to be distinguished from hypertensive disease, a symptom of an acute abdomen, vasorenal hypertension, diabetes mellitus, toxic goiter, vegetovascular crises.
It has the greatest similarity with hypertensive disease of stages I and II.The process of diagnosis is complicated by the fact that hypertensive disease is characterized by crises, the clinic of which is similar to pheochromocytoma, and it is characterized by an increase in blood pressure. When differentiating these diseases, attention is drawn to the age of the patient( at the risk of hypertension younger than 40 years).When a combination of a tumor and diabetes mellitus, insulin is ineffective.
Diagnosis of
The diagnosis of "pheochromocytoma" can be made only after a series of laboratory, instrumental and differential studies. The main material for the study is a 24-hour urine test. The content of physiologically active substances in it( concentration of metanephrin) is determined. This method has an accuracy of 95%.The basis for the diagnosis is an increased content of catecholamines. To confirm it, determine the concentration of free catecholamines in urine or blood plasma. Use provocative and suppressive tests. Also on the basis of laboratory diagnostics, the tumor is visualized.
Everyone should undergo medical examination immediately if symptoms of pheochromocytoma appear. The duration of the incubation period of the disease allows us to detect the tumor in time and begin therapy.