Analysis for cationic eosinophilic protein is prescribed when the patient suffers from allergies or bronchial asthma. This study shows how active the disease is at the moment. This diagnostic method is not used often and is not carried out in all laboratories.
What is an ECP?
The blood contains white blood cells - white blood cells, which are divided into several types. One of the varieties is eosinophilic granulocytes (or eosinophils). If you look at these cells under a microscope, you can see granules inside their cytoplasm. Eosinophilic cationic protein (ECP) is part of these granules. It is a protein with a positive charge.
In allergic reactions, ECP enters the bloodstream. The same phenomenon occurs during helminth infestations, since this protein has a toxic effect on parasite cells. And with allergies, ECP is intensely produced by eosinophils. This protein increases the production of mucus in the airways, affects blood coagulation and the formation of immune cells. In allergies, an eosinophilic cationic protein is released from the cytoplasm. What does such a reaction mean? This is the body's response to the interaction of the allergen and immunoglobulins.
Why are they tested for ECP?
Allergists and pulmonologists sometimes prescribe an analysis for an eosinophilic cationic protein. What does this study show? The level of ECP in the blood indicates the severity of eosinophilic inflammation in allergies and helminth diseases. With bronchial asthma, you can notice a pattern: the more severe the symptoms of the disease, the higher the level of cationic eosinophilic protein. The higher the ECP, the harder the pathology. We can say that this protein is a marker of exacerbation of allergies.
This analysis is also necessary in cases where the patient is undergoing treatment for an allergic or helminth disease. A decrease in ECP indicates the effectiveness of therapy.
In what cases is an examination prescribed?
A blood test for cationic eosinophilic protein is prescribed if the patient has the following symptoms:
- difficulty breathing or asthma attacks in contact with animal hair, pollen, dust;
- rashes on the skin, accompanied by itching;
- runny nose or sneezing on contact with allergens;
- skin rashes, swelling of the nasopharynx, sneezing and dyspeptic symptoms after eating certain types of food.
However, just a single blood test for ECP is not enough to make an accurate diagnosis. Usually, additional tests are required.
Deciphering the results
In what quantities should an eosinophilic cationic protein be contained in blood serum? The norm is from 0 to 24 ng / l. Typically, the ECP content corresponds to the eosinophil count.
With some pathologies, this figure can be significantly higher. So with bronchial asthma, the ECP indicator can exceed the norm by 2-3 times.
Sometimes the analysis reveals very high rates (about 240 ng / l) of the eosinophilic cationic protein. What does such a serious aberration mean? This indicates either infection with helminths (usually schistosomes), or an exacerbation of atopic dermatitis.
In some cases, the ECP values exceed the norm by several tens of times (about 700 ng / l). Typically, such numbers are found in hypereosinophilic syndrome. This is a fairly serious disease associated with impaired blood formation.
Sometimes you can notice how, after treatment, the eosinophilic cationic protein begins to decrease gradually. What does this result show? This indicates the effectiveness of the prescribed therapy. Using the ECP study, the required dosage of drugs for patients with asthma is calculated.
What diseases does the analysis detect?
If the result of the analysis is not more than 24 ng / l, then this is considered a variant of the norm. Deviation is considered only the excess of this figure. It happens with the following diseases:
- acute infections of the upper respiratory tract (rhinitis);
- polyps in the sinuses of the nose;
- an allergic form of bronchial asthma;
- bronchial asthma due to intolerance to aspirin;
- food allergies;
- atopic dermatitis;
- allergic rhinitis with seasonal exacerbation;
- hypereosinophilic syndrome;
- helminthic invasion;
- allergic inflammation of the esophagus, stomach, intestines;
- eosinophilic pneumonia of autoimmune origin (Charge-Strauss syndrome);
- allergic conjunctivitis;
- taking certain drugs (antibiotics, non-steroidal anti-inflammatory drugs, "Carbamazepine", "Phenobarbital", "Co-trimoxazole", "Phenytoin", "Glimepiride".
A reduced protein level is not very important for diagnosis.
An increase in cationic protein in children under 1 year old is not always associated with allergies. This can be caused by Rh conflict, pemphigus, infectious and fungal diseases.
How to prepare for the examination?
A few days before the scheduled analysis, it is necessary to exclude the use of drugs that may affect the results of the study. These drugs include:
- antibiotics
- tranquilizers;
- interferon medications;
- laxatives containing plantain;
- central nervous system stimulants.
And also a few days before the analysis, it is not recommended to eat fatty foods, drink alcohol. Before the study, you can not smoke, do heavy physical work, drink sweet tea, coffee, juices.
An analysis is given in the morning on an empty stomach. Stop eating should be 8-12 hours before the study. You can drink only clean water.
How do the analysis?
To conduct a study on cationic eosinophilic protein, blood is taken from a vein. Then the test tube with the material is sent to the laboratory. The blood is centrifuged to separate the red blood cells. Serum is studied by immunochemiluminescent method.
This research method is based on the reaction of an antibody with an antigen. The protein contains arginine, an amino acid that is determined using monoclonal antibodies.
This is an informative research method, which in 90% of cases gives reliable results. In diagnostic laboratories, the analysis is done quite quickly, usually the results are known after 1-2 days.
What to do with increased ECP?
The patient is always worried when he finds out that he has an increased eosinophilic cationic protein. What to do in this case? It all depends on the cause of this deviation.
If the patient previously had signs of allergic reactions, then contact with substances that provoke an exacerbation of the disease should be avoided. The doctor will prescribe a course of treatment with antihistamines. If the allergen is unknown, then skin tests will be required to determine the type of irritant.
If the patient has never had signs of the disease before, then a slightly increased ECP may indicate a tendency to allergies. In this case, usually an additional test for immunoglobulin and leukocyte formula is taken.
It must be remembered that an increase in cationic protein can be associated not only with allergies, but also with helminth invasion or blood diseases. It may be necessary to take an analysis for eggs of worms and protozoa, a consultation with a hematologist.
If an increase in ECP is associated with medication, then usually this phenomenon is temporary. After the course of treatment, all blood counts return to normal.
It is very difficult to figure out on your own the reasons for the increase in cationic protein. First of all, it is necessary to show the result of the analysis to your doctor. Therapy of such conditions involved: allergist, pulmonologist and dermatologist.