Diaskintest - the best test for tuberculosis
Everyone has heard of such a serious illness as tuberculosis, but few have come across it in life. Many mothers and fathers consider the risks of contracting this disease exaggerated, and the illness contrived, therefore, they refuse vaccination and diagnostic tests for their child.
In fact, to prevent infection with a dangerous infection is one of the main tasks of public health, massive preventive measures are being held in the country. In recent years, in addition to the usual Mantoux reaction, Diaskintest is used to detect tuberculosis, which causes many questions from parents. To understand whether vaccinations and tests for tuberculosis are needed, it is necessary to understand the main ways of preventing infection.
Infection with a dangerous infection develops after ingestion of mycobacteria, which are also called “tubercle bacilli”, or Koch's bacillus. Under favorable conditions, the microorganism multiplies rapidly and most often affects the patient’s lungs. But sometimes the infection does not affect the respiratory system, but extends to the bones and joints, skin, nervous tissue and other organs.
The incidence of tuberculosis in Russia remains high, and the number of infected children has doubled in the last decade. About 2% of the total number of children’s population are annually registered with tuberculosis dispensaries.
The course of the disease in children differs from the classical development of the disease. For children, small and uncomplicated forms of tuberculosis, damage to the intrathoracic lymph nodes are more characteristic. Extrapulmonary manifestations do not exceed 10% of the total number of cases of infection.
About vaccines and diagnostic tests
- vaccine against tuberculosis.
BCG is a vaccine and is based on a bovine type of tuberculosis bacterium. The injected microorganism, although alive, is weakened so much that the baby’s immunity easily copes with it. After vaccination, the child remains reliable protection, and the Mantoux test can be positive.
Vaccination is carried out to all newborns according to the vaccination schedule on days 3–7 after birth. Repeated administration of the vaccine is possible at the age of 7 and 14 years if the child has evidence
- Mantoux test and its meaning.
This test is performed using tuberculin - a special extract obtained from dead bacteria. This substance is an allergen and causes a response in carriers of mycobacteria and people vaccinated against tuberculosis. A positive Mantoux test indicates that the child is infected, but this does not always mean that the disease has developed.
- Diaskintest for tuberculosis, what is it?
The diagnostic test contains special proteins - antigens that trigger an immune response in the body when infected with mycobacteria. These substances are absent in the vaccine against tuberculosis, therefore Diaskintest is considered more specific than the Mantoux reaction.
It turns out that this test is more selective, and its positive result indicates infection of the baby with a dangerous bacterium, the development of the disease. But why did Diasintest not completely replace the Mantoux test? It turns out that, due to its specificity, the reaction itself cannot be used in the selection of children for repeated BCG vaccinations, but can be an addition to the intradermal tuberculin test.
General indications for Diaskintest
- detection of a fasting lung disease,
- assessment of tuberculosis,
- differential diagnosis of the disease,
- the difference in post-vaccination allergy from the infectious process,
- identifying children at high risk of developing the disease,
- as part of a comprehensive assessment of the effectiveness of the treatment.
How is Diaskintest conducted?
Before making a test, the child must be consulted by a doctor. The test is identical to the Mantoux test. For this, tuberculin syringes and short needles are also used, and the injection itself is carried out intracutaneously.
A nurse dials 2 doses of a diagnostic tool into a syringe, one of which is discharged onto a sterile cotton swab. Thus, a more accurate dosage of the drug is achieved. Then the health worker determines the place of the sample - the middle third of the inner surface of the forearm. Baby's skin is treated with alcohol, after which 0.1 ml Diaskintest is injected.
At the point of introduction of the diagnostic substance, a papule appears in the form of a “whitish-colored lemon peel” with a diameter of 7-10 mm.
How to evaluate the reaction to Diaskintest?
To understand how the body responded to the drug, 72 hours after the test was set, the seal size was determined with a transparent ruler and the result was evaluated:
- Negative reaction
After the prescribed time on the skin of the child are not determined traces of the injection. A small “prick reaction” can be formed, up to 2 mm, at the place of the test. The negative results of Diaskintest indicate the absence of mycobacteria in the child’s body, which is normal in children. The baby does not belong to the risk group for the development of tuberculosis.
- Doubtful reaction.
Sometimes redness occurs at the injection site, but there is no pronounced tissue consolidation. This indicates the need for additional examination of the child, the conduct of other diagnostic methods.
- Positive reaction.
If a seal has formed on the child's skin, a papule of any size, we can speak of a positive test result. The greater the magnitude of the element, the more pronounced the reaction is considered.
Contraindications to Diaskintest
But not always a diagnostic test is possible. Like any drug Diaskintest has its contraindications:
- infectious, atopic and malignant skin diseases,
- allergic diseases in the acute stage,
- exacerbation of chronic diseases or acute signs of illness,
- infectious diseases (testing is possible only a month after the clinical recovery of the patient),
- The test is contraindicated if less than a month has passed since the last vaccination.
Adverse Reactions to Diaskintest
The sample is well tolerated by children, and undesirable reactions occur in very rare cases. Of the possible negative manifestations of the manufacturer of the drug indicates a headache, weakness, fever. In some cases, a hematoma is formed at the injection site. A bruise makes it difficult to evaluate test results and increases the risk of diagnostic errors. Hematoma formation is usually associated with improper testing techniques.
Frequently asked questions to the doctor
Since Diaskintest is used relatively recently, parents of young patients have many questions about the diagnostic test. Consider the most common ones:
- At what age is Diaskintest allowed to conduct?
The manufacturer notes the possibility of using an intracutaneous test in all age groups, indicating the absence of any age restrictions.
If a baby under 7 years old has a positive reaction to a Mantoux test, the TB doctor may recommend additional staging of Diaskintest. After the child reaches the age of 8 years and up to the age of 17, Diaskintest is shown every year.
- Is it possible to do both diagnostic tests on the same day?
In case of doubts with the TB doctor regarding the authenticity of the Mantoux test, the doctor may recommend doing both reactions. Experts allow simultaneous execution of Mantoux and Diaskintest tests, subject to testing on different hands.
- Is water hazardous to the sample site?
Everyone has heard that Mantoux is not worth drenching, but what about Diaskintest? Although water, in most cases, does not have any negative effect and does not affect the results of both samples, it is still necessary to exercise caution.
- Is it possible to combine the Diaskintest test and vaccination?
The diagnostic test should be assessed before the next vaccination, so it is better to first diagnose and then vaccinate on the calendar. If the baby was recently vaccinated, it is necessary to postpone the diagnosis of tuberculosis for a month. After this period, it is worth holding Diaskintest, then its results will be reliable.
- What to do if it's time to do the test, and the baby is sick?
If the child has signs of ARVI, it is recommended to postpone the test until the baby is fully cured. In the case of an exacerbation of the crumbs of a chronic disease, you should first take care of the health of the child, and then use Diaskintest.
If you are prone to allergic reactions in a child, you need to prepare in advance for the test - give the crumbs desensitizing drugs 5 days before the test and 2 days after it. If the child is registered with an allergist, for example, with bronchial asthma, it is necessary to consult a doctor before making a diagnosis.
- Is it allowed to test the child in the clinic, if the garden is closed for quarantine?
If an infectious disease is detected in a preschool institution, quarantine measures are required. Even if the baby looks healthy, you need to wait until the end of the forced break and then test.
- Should I adhere to a diet during the diagnosis of tuberculosis?
The manufacturer of the drug does not indicate the need to limit any products with the introduction of Diaskintest. Doctors advise not to eat food, which can provoke allergic reactions in a child. It is necessary to avoid any contact with potentially hazardous substances, not only in products, but also in the environment. This is especially true of children who are prone to manifestations of hypersensitivity.
- Is it safe to use Diaskintest in children's practice?
In the case of the correct administration of the drug, compliance with the correct dosage, the sample does not adversely affect the health of the baby. Parents should understand that Diaskintest, like any antigen, can cause general reactions in the form of weakness, headache, fever. But such manifestations occur in rare cases and do not cause harm to the body.
- What should be the result of testing in a healthy person?
The reaction to Diaskintest should be negative regardless of the age and the fact of immunization of the child. With Mantoux, things are different - for a baby who has not yet received a BCG vaccine, the tuberculin test should be negative. After vaccination, the reaction becomes slightly positive or positive, indicating the formation of immunity against tuberculosis.
- Is it possible to prescribe prophylactic treatment against tuberculosis on the basis of diagnostic tests?
With the advent of a new diagnostic test, the number of unreasonably prescribed treatments has decreased. Children with a positive Mantoux test and a negative Diaskintest are completely healthy, and their immunity works.
Tuberculosis prevention has received much attention in our country. And it is not surprising, because the disease is much easier to prevent, and in case of infection with an infection, it is necessary to prescribe proper treatment in time. Therefore, all babies are given BCG vaccination and diagnostic tests.
The use of a new type of diagnosis - Diaskintest allows you to more accurately identify the disease. This method is quite specific, and its reliability is close to 100%, which helps to determine tuberculosis in the early stages and understand the need to treat an infectious disease. Understanding the importance of conducting diagnostic tests and vaccinations, knowing what Diaskintest is, vaccinations, parents will be able to protect their child from such a dangerous disease as tuberculosis.
Vaccination or sample?
The essence of the drug lies in its name. Diaskintest (DST) is a test, not a vaccine. It reflects the body's reflex to the activity of tuberculosis sticks and helps prevent the development of a serious illness. This is the response of the immune system to the penetration of protein allergens into the body, which states how familiar it is with these antigens. A positive reaction indicates: “sign” is infected or sick.
Since 2015, the drug is used in the detection of tuberculosis in children 8-17 years old. In children up to seven years old, inclusive, the mass diagnosis of the disease remains the same. Mantu and Diaskintest are similar in their action, but the positive reaction of DST is an indisputable indication for the start of anti-tuberculosis chemotherapy.
Behavior after injection
The algorithm for applying Diaskintest and Mantu is the same. Children DST do only 30 days after the previous vaccination, while the child must be completely healthy.
Experimentally defined rules that should be followed before evaluating the test:
- It is not necessary to take water procedures, despite the fact that the injection site is allowed to wet,
- It is not recommended to scratch, rub the "button", steam it up, smear it with something "for healing", seal it with adhesive tape or wrap it up with bandages,
- Sports training should be postponed - sweat can distort the reaction by changing the minus to plus,
- It is necessary to refrain from sunbathing and walking in severe frost.
Evaluation of results
Both Mantu and Diaskintest, evaluating the reactions, rely on the same criteria. Three days after testing, the magnitude of hyperemia and infiltrate at the injection site is analyzed. There are three reaction options:
- Negative - redness and papule are missing or the red spot does not exceed two millimeters in diameter,
- Doubtful - with obvious reddening there is no papule,
- Positive - visible papule.
Evaluate testing should be a specialist. The norm for both adults and children is considered one result of DST - negative. The reaction to Diaskintest by day does not matter. Hyperemia can occur on the first day and the third.
The result is considered negative if there is no change in the injection site. This means that there are no active mycobacteria in the body. At the injection site is sometimes visible trace of the injection itself. An unsuccessful injection may even cause a bruise (hematoma). A bruise at the injection site can distort the test, “disguising” the redness. Sometimes this reaction is considered doubtful, the patient is sent for additional examination, since secondary testing with the drug is possible only after two months.
The manifestation of the inflammatory reaction to Diaskintest in the form of infiltration is a positive result. The more Koch sticks in the body, the larger the seal. Positive manifestations are:
- weak (papule less than 5 mm),
- moderate (infiltrate 5-9 mm),
- pronounced (papule 10-14 mm),
- hyperergic - infiltrate reaches 15 mm and more, there is a crustal and vesicular structure, lymph nodes inflamed (papule size does not matter).
A positive DST result indicates inflammation. But infection does not mean that the disease will develop. A strong immune system is able to overcome pathogens. At the same time, in the area of infiltration, a Gona focus or calcinate is formed, provoking a positive Mantoux reaction. It may be doubtful.
Causes of false positive results
Diaskintest is false positive (positive in the absence of tuberculosis). This fact signals negative changes in the body. There are several reasons for these reactions:
- The test was carried out despite contraindications (sometimes the patient himself does not know about them),
- The injection site is infected (usually seen in children),
- Allergic pathologies (inadequate reaction to antigens),
- The presence of autoimmune diseases.
To minimize the possibility of false-positive results, Diaskintest should be done strictly in the absence of medotvod. Adults before and after the test can not drink alcoholic beverages.
Important! The results of Diaskintest correlate in effectiveness with QuantiFERON tests. In contrast to the expensive reagents of the "gold standard" of phthisiology, DST is used massively.
What is Diaskintest
Compared with the Mantoux reaction, this medical drug tester is a relatively new development of modern scientists. This is not a vaccine, but a test sample that is capable of diagnosing the latent form of tuberculosis with maximum accuracy. Mantu and Diaskintest, in fact, have the same purpose, but in the latter case, a positive test means the absolute indication for a course of chemotherapy against tuberculosis. When the phrase “Diaskintest” was sounded - that not all patients know this, many people are more accustomed to hearing about Mipert's hyperergic reaction.
How do Diaskintest
Основой инновационного средства являются белковые аллергены, которые врач подкожно вводит пациенту, чтобы определить реакцию последнего на такие инородные тела. Если в химическом составе крови уже присутствуют аналогичные вещества, это значит, что туберкулезу свойственна скрытая форма, и клинический больной становится носителем туберкулезной палочки. It is possible that the disease produces in the active stage, requires the immediate start of intensive therapy. If the answer is negative, therapeutic and recreational measures are not required.
The patient knows which hand Diaskintest is placed in, since this is an inoculation analogous to Mantu. In fact, the hand does not matter, but the mandatory area is the area of the forearm to reduce the discomfort for the patient during the procedure. Doctors recommend choosing the hand that is less involved in everyday life, where only a small load falls (for the vast majority of cases it is the left forearm). Otherwise, the sequence of actions is well known to every nurse.
All patients are interested not in the process of performing the test, but in the result obtained. This is especially true of people from the so-called risk group, in whom the Mantoux reaction is always pathologically increased. For those who are not aware of what Diaskintest is showing, it is worth clarifying: this modern sample, administered subcutaneously, determines the presence or absence of tubercle bacillus in the blood. A positive response is fatal, requires immediate medical participation, treatment. Negative indicates impeccable human health in terms of the diagnosis of tuberculosis.
If this modern test for tuberculosis Diaskintest is performed, the patient needs only to wait for results, to observe changes in the condition of the skin. If on the same day or every other day there is an obvious reddening with further papule formation, this is a clear sign of an inflammatory process, although in reality the answer may be false positive.
The reaction to Diaskintest for adults and children increases over the course of three days, after which it will not be possible to accurately determine the presence of the pathological process. It is required to contact a phthisiologist who knows exactly what a positive d-test should look like. Also useful information can be found in the instructions for this drug.
If there is a hyperemia of the skin in the place of the direct injection, doctors do not exclude that the reaction to Diaskintest is false positive. This is encouraging, because in fact, the tubercle bacillus in the blood may not be. For the examination of such a clinical picture of the patient is sent to a tuberculosis dispensary, where they put on a dispensary account. In the future, it is recommended to conduct a series of clinical and laboratory studies, and after 2 months to re-run the test Diaskintest and get a reliable result.
Before you panic and worry about your health, it is recommended to check with your doctor what Diaskintest should be normal. The ideal option is a colorless seal with a diameter of 1 mm, a barely noticeable mark from the injection or a small bruise. Redness, which will be very itchy and accompanied by the formation of papules of impressive size, certainly does not appear in the forearm area.
When Diaskintest is contraindicated for tuberculosis
This sample is a modern development of scientists, leaves far behind the obsolete Mantoux reaction. However, this test is not allowed to all patients, because the instructions contain contraindications for Diaskintest and potential side effects. So, the vaccine cannot verify the presence of the tubercle bacillus in the following categories of patients, not recommended for such clinical pictures:
- viral and infectious diseases of the recurrence stage,
- predisposition to allergic reaction,
- bronchial asthma, skin diseases,
- cold, runny nose, fever,
- systematic alcohol abuse
- allergic to tuberculin, other synthetic components of the specified drug.
- Carefully perform the test during pregnancy, but the lactation period is not a relative contraindication.
Diaskintest - what is it (essence and general principles)
Diaskintest is a method for diagnosing tuberculosis, which is similar to the Mantoux test in terms of its performance, but in essence the reaction in the body to a quantiferon test. Let's take a closer look at what this means. Thus, for the formulation of diaskintest, a fluid containing intracellular proteins is injected intracutaneously, which is found on the pathogenic bacteria Mycobacterium tuberculosis, which cause the disease of tuberculosis. Since only individual proteins are intradermally injected, diaskintest by no means can lead to infection with tuberculosis.
And then, after three days (72 hours), the response of the body in the area of administration is evaluated by the presence of redness, compaction, etc. If at the injection site there is a reaction in the form of redness or compaction, then the result of diaskintest is considered positive. If, on the injection site, only a point from a needle puncture of the skin is visible, the test result is negative.
A positive result of Diaskintest means that the human body is familiar with Mycobacterium tuberculosis, that is, its immune system has “recognized” the introduced intradermally characteristic proteins and has given them the appropriate response. But, unfortunately, a positive test result does not allow to distinguish active tuberculosis from asymptomatic carriage of mycobacteria, and therefore with this result diaskintest will have to undergo additional examination in order to identify / exclude active tuberculosis.
A negative test result means that the human body is not familiar with Mycobacterium tuberculosis, that is, the immune system "did not recognize" foreign proteins introduced under the skin, and, accordingly, it is not sick with tuberculosis and is not an asymptomatic carrier of mycobacteria.
A positive or negative result of diaskintest depends on whether the human body reacts to the mycobacterial proteins injected under the skin, which are called CFP10 and ESAT6. These proteins are on the surface of mycobacteria causing tuberculosis and are considered antigens. If such proteins are introduced into the body (in the case of Diaskintest, they are injected intracutaneously), then the immune system will first try to recognize them (“learn”). And if the immune cells “recognize” the mycobacterial proteins, they will immediately begin to produce antibodies to destroy the foreign genetic material in the body, which will manifest itself as a positive result of diaskintest.
But the "recognition" of mycobacterial proteins depends on whether the Mycobacterium tuberculosis itself has previously been taken into the human body. That is, if in the past a person was infected with mycobacteria, the immune cells “recognize” them, quickly develop antibodies, which will manifest a positive reaction to diaskintest. If, in the past, a person was not infected with mycobacteria, the immune cells will not be able to “recognize” the proteins introduced intracutaneously, which will manifest as a negative reaction to diaskintest.
Thus, it is obvious that a positive result of diaskintest is observed in those people who have mycobacteria in the body. A negative result of diaskinesta, respectively, is characteristic of those who have never been infected with mycobacteria. But a positive result does not mean obligatory disease of tuberculosis, but only indicates infection with mycobacteria. Here, to understand this fact, it is necessary to make an explanatory digression.
So, mycobacteria are widespread and about 90% of the adult population of Russia is infected by them. Features of the structure and life cycle of mycobacteria lead to the fact that after entering the human body, they remain in it for life, since it is almost impossible to remove them using antibiotics available in the arsenal of modern medicine. But because of the complexity of the life cycle and the interaction of mycobacteria with the human body, such infection with them leads to the development of tuberculosis by no means always, but on the contrary, even very rarely. Thus, according to modern statistics, among all people infected with mycobacteria, tuberculosis develops on average only in 2% (in risk groups - in 5 - 10%). That is, the overwhelming majority of those infected with mycobacteria will live quite peacefully throughout their lives and will never get sick with tuberculosis. But in reality only 2 - 10% of people infected with mycobacteria get sick during their lives.
A condition where a person is infected with any pathogenic bacteria, but lacks the disease they cause, is called asymptomatic bacteriocarrier. A person infected with mycobacteria does not release them into the environment and, accordingly, is not a source of infection for other people. Currently, in connection with the campaign announced by WHO (World Health Organization) to minimize the incidence of tuberculosis, a state of asymptomatic bacteriocarrier, when there are mycobacteria in the body, and there is no active tuberculosis, is called a latent tuberculosis infection. It was recommended that people with latent tuberculosis infection should be treated prophylactically with anti-tuberculosis antibiotics to prevent the development of tuberculosis in the future. Similar recommendations have been adopted in many countries, including Russia.
Thus, Diaskintest makes it possible to detect the presence of Mycobacterium tuberculosis in the human body, but the test does not make it possible to distinguish active tuberculosis from asymptomatic carriage. Therefore, x-ray / fluorography, computed tomography, ultrasound, urinalysis for mycobacteria, etc. are prescribed as additional methods of examination to distinguish carrier from active tuberculosis with a positive diaskintest.
Sensitivity and Specificity of Diaskintest
The specificity of the method reflects the percentage of cases when it gives a positive result in the absence of infection with mycobacteria. That is, the specificity of diaskintest is the percentage of false-positive results. The specificity of diaskintest, in contrast to sensitivity, is rather high and amounts to 98 - 99%. This means that Diaskintest gives a false positive result only in 1 person out of 100. False positive results are due to the fact that a person can be infected with certain types of mycobacteria (M. kansasii, M. leprae, M. marinum) that never cause tuberculosis, and provoke other diseases. But these non-tuberculous mycobacteria also have on their surface the proteins ESAT-6, CFP-10, the introduction of which in the process of conducting diaskintest reacts to the human body, giving a positive test result.
What does diaskintest (his appointment) show
Diaskintest shows whether a person is infected with mycobacteria that can cause tuberculosis. If the test result is positive, then infection with mycobacteria occurs. If the test result is negative, then the person is not infected with mycobacteria.
Unfortunately, Diaskintest does not allow to determine whether there is a simple infection with mycobacteria (a person is a carrier of bacteria, but does not have tuberculosis), or a person is sick with tuberculosis. To distinguish the asymptomatic carriage of mycobacteria from the disease of active tuberculosis, it will be necessary to conduct additional examinations (x-rays, tomography, blood and urine tests, etc.).
In addition, Diaskintest makes it possible to distinguish whether a positive Mantoux test is due to a tuberculin allergy, or a BCG vaccine previously given, or infection with mycobacteria. If the Mantoux test is positive due to an allergy or a BCG vaccination made in the past, then such a person will have a diaskintest negative. But if the Mantoux test is positive due to infection with mycobacteria, then the diaskintest of such a person will also be positive, which will confirm the result of Mantoux.
In addition, Diaskintest allows you to track the effectiveness of ongoing anti-TB therapy. After treatment of active tuberculosis or after prophylactic treatment, if they were effective, diaskintest becomes negative.
However, given the fact that administration of the diaskintest drug does not cause a reaction in people who have received a BCG vaccine in the past, the result of this examination cannot be used to select children and adults for re-vaccination of BCG.
Indications and contraindications to diaskintest
Diaskintest is shown for intracutaneous testing of people of all ages with the following objectives:
- Diagnosis of active tuberculosis of various organs (lungs, kidneys, lymph nodes, etc.),
- Identification of people with a high risk of developing active tuberculosis of any organs (infected with mycobacteria or, as the state is called in official documents, with “latent tuberculosis infection”),
- With the aim of differential diagnosis of an allergic reaction to the Mantoux test (after BCG vaccination or against the background of an allergic body constitution) and tuberculosis,
- To assess the effectiveness of the treatment of tuberculosis and preventive therapy.
Currently, according to the orders of the Ministry of Health, diaskintest as a way to diagnose tuberculosis is necessarily carried out to all healthy children of 8–18 years old once a year (instead of the Mantoux test). If the child has not received BCG vaccinations, diaskintest is done twice a year. Diaskintest can also be prescribed for the diagnosis of tuberculosis and adults as part of a routine checkup. If a child or adult is registered with a phthisiatrician, then diaskintest may be administered once every 3 to 6 months.
In addition, Diaskintest is indicated for a questionable result of a Mantoux test, when it is necessary to understand whether a positive or dubious result of Mantoux is due to allergies, BCG vaccination or developing tuberculosis.
Diaskintest is contraindicated in the following diseases and conditions:
- The presence of skin diseases with a large number of rashes, pustules, etc.,
- The acute period of any diseases, including ARVI, sore throats, colds, etc.,
- Exacerbation of various chronic human diseases of any organs
- The period of exacerbation of allergic diseases
- Increased body temperature
- Quarantine for infections in institutions where people work or study
- Vaccination during the month before the diaskintest,
- Individual intolerance or allergic reaction to the components of diaskintest.
If at the time of the test there is a high probability of infection with an infectious disease (for example, influenza, ARVI, etc.), then it is better to postpone Diaskintest, because in such a situation, when infection has already occurred, but the disease has not yet developed, the risk of a false positive is very high. Diaskintest make two months after suffering an acute infection, such as scarlet fever, bronchitis, etc.
Since the effect of the diaskintest drug on pregnancy and fetal development has not been studied, in pregnant women diaskintest is used as part of a comprehensive diagnosis of tuberculosis only when the benefit outweighs the potential risk for the unborn child.
How often do diaskintest?
For healthy children aged 8–18 years, Diaskintest is done once a year as part of a mass screening for tuberculosis. If the child has not received a BCG vaccine, then diaskintest is done twice a year. As an adult, diaskintest is also performed once a year as part of a preventive examination. But if a child or an adult suffers from diabetes, gastric ulcer or duodenal ulcer, diseases of the bronchi, lungs or kidneys, HIV infection, immunosuppressive drugs are given, then diaskintest is performed twice a year, every 6 months, as part of a preventive examination.
Children are allowed to put diaskintest with a positive Mantoux test from the age of one year.
In all other cases, the multiplicity of Diaskintest staging is determined by the doctor, and in doing so, he is guided by the following rules:
- In case of a negative result of the diaskintest, the sample can be retested after 2 months
- If the result is positive, diaskintest can be repeated at any time intervals as needed,
- After setting any vaccination - no earlier than a month later,
- After suffering any acute infectious diseases - not earlier than in a month.
From what age and up to how many years you can do Diaskintest
There are certain health standards adopted in the Russian Federation that clearly define how often a test can be done to detect tuberculosis bacteria, from how many years and to what age they are made. Parents should remember:
- Children and adolescents do Diaskintest from eight years to seventeen, if the doctor has not appointed another method of examination for tuberculosis infection.
- Kids as young as one year old are allowed to put Diaskintest if they have made Mantu before, and the reaction was positive.
Почему Диаскинтест считается лучшим в сравнении с Манту, но при этом можно делать Диаскинтест детям только от года, да и то лишь в крайних случаях, а Манту – с рождения? Объясняется это вовсе не токсичностью нового препарата, напротив, он более качественный и безопасный, чем аналоги. Но, тем не менее, у малышей может появиться аллергия на него, так как в составе – только чистый белок. А белок любого вида потенциальный и очень мощный аллерген, справиться с которым организм новорожденного еще не в состоянии. In this case, older children tolerate the sample remarkably, allergies appear only in a few, the cause is usually a congenital tendency to intolerance to drugs or a poor-quality drug, for example, if the expiration date has almost expired.
The result of Diaskintest may be affected by the presence of helminth infection in a child or adult. Parasitic lesion causes allergies. An infected person’s immune response fails. Diaskintest in the presence of worms is often positive. Take a new drug before the test, against most of the known parasites Intoxic, to be sure that the result of the study is reliable.
How long is the result, frequency of checks
How often a diaskintest can be done without compromising health is an equally important question. If the previous reaction to diaskintest was doubtful, if the child has undergone a course of treatment or needs to evaluate the effectiveness of the therapy, the doctor prescribes a series of repeated studies, among which Diaskintest. How safe is it really? After all, it is known that the active substance of the test is the basis of BCG vaccination. Does the child get tuberculosis bacteria together with the drug and does not provoke too frequent testing of the development of a dangerous disease?
No, like Mantoux, Diaskintest is not a vaccine and, together with its introduction, the child does not receive the Office. The frequency of the samples, how much time must pass between them and other studies or vaccinations - all this is also spelled out in health care standards:
- All examined persons over the age of eight are given a test once a year - provided that the subject had not had a positive Mantoux test. By the way, Mantoux for younger children, according to the norms of health care in Russia, is made twice a year.
- If a patient is registered in a TB dispensary and undergoes a course of treatment, control checks are performed at a frequency of once every 3-6 months.
- If a person has been vaccinated (for example, a BCG vaccine), Diaskintest is allowed to be given only after 30 days, otherwise the results of the study may be distorted.
- Also, 30 days must pass from the moment of complete recovery from an infectious disease.
- In the event that the results of Diaskintest were dubious or negative, retesting is done only after two months.
What else is worth knowing? In essence, Diaskintest does not replace Mantu, but only confirms for sure a positive reaction. Sometimes they are performed simultaneously by both Mantu and Diaskintest in the forearms of the right and left hand. What for? It's all about the different composition of two different drugs. Diaskintest contains the protein of a bovine strain of tuberculosis, so if a person is infected with this type of bacteria, the test will be negative. But then Mantu will react to such a pathogen. And, vice versa - where Mantu will give a negative or dubious result, Diaskintest will help clarify the real picture. Doctors recommend not to shy away from tests for tuberculosis. As for the Mantoux tests, there were also heated debates at one time; many parents were seriously convinced that they were infecting their child with tuberculosis. So it is with Diaskintest. But to fear in this case should be the disease, and not a possible allergic reaction to it, which, if the shelf life and storage conditions are not violated, most likely will not.
Sample "Diaskintest" - what is it?
Diaskintest is a special medical product used for the prophylactic diagnosis of tuberculosis. The sample contains two synthetic antigens that respond to Koch's wand. If a person is sick, then 2-3 days after the introduction of the allergen into the body, redness is formed at the injection site, and swelling (the actual reaction is an allergic reaction). If a person is healthy, then redness and swelling in the area of the injection is not observed.
The accuracy of the test is approximately 90%. In its pharmacological properties, Diaskintest is very similar to the Mantoux test, but less often gives false positive results, which increases the medical value of such a test.
When an injection is administered, a weakened Koch wand is not injected into the body, therefore it is impossible to become infected with tuberculosis through an injection, it is completely safe for the human body, so it can be administered to people at any age.
The preparation also includes water for injection, salts, phenol and other substances. It should be understood that the concentration of phenol in Diaskintest is very small, when injected into the body about 0.25 mg of phenol is ingested, which is a safe dose for both adults and children.
How is the test performed?
To conduct the test with the help of "Diaskintest" should an experienced doctor. For the introduction of the drug using a special syringe with a thin needle. The dose of the drug is 0.1 ml. The injection is usually done in the left hand (if the person is left-handed, then the drug is injected into the right hand). The injection is done in a sitting position; immediately after the injection, the injection site turns red. 3 days after the injection, during the examination, the doctor assesses the size of the redness, the nature of the skin seal and some other parameters.
You should also remember the rules after the test:
- Diaskintest is allowed to wet only with clean water.
- There are no food contraindications. The use of sweet, sour, smoked and other products is allowed.
- Within 3 days after the test, it is necessary to avoid contact with chemically active substances (soap, shampoo, etc.). Also, the injection site can not be treated with drugs.
- The injection site can not be scratched.
- The injection site must not be sealed or rewound with medical dressings.
- After the introduction of the test, it is necessary to postpone sports training, because sweat can distort the test results.
- Also, after the injection should avoid exposure to high and low temperatures. Therefore, after the injection of sunbathing, walking in the cold and so on.
Why do we need "Diaskintest"
The test with the help of "Diaskintest" is needed for the diagnosis of tuberculosis. During the injection, two synthetic antigens are introduced into the human body that can be recognized by the body. If the person is sick, then 3 days after the injection, the injection site will turn red and harden. Also, a sample is made before vaccination.
Vaccination is good for tuberculosis, but the vaccine needs to be administered only to a healthy body to avoid complications. Therefore, before the introduction of the vaccine, it is necessary to diagnose, and this task can be performed by Diaskintest.
It should also be remembered that after vaccination, it is necessary to do a test using Diaskintest only after 30 days, because during vaccination, a weakened Koch stick is specially introduced into the body to develop protection, which distorts the test results.
Who can and can not do the test
The use of Diaskintest is required in the following cases:
- Diagnosis of tuberculosis.
- Evaluation of the activity of Koch sticks in the human body, if the presence of tuberculosis is already established.
- Differentiated diagnosis of diseases. The fact is that the symptoms of tuberculosis are in some cases very similar to the symptoms of some other diseases, so with the help of Diaskintest, one can unambiguously identify or refute the suspicion of infection of the body with a Koch sticks.
- Diagnosis in cases where the use of other tests is impractical (or there are many contraindications to them).
Very often, children are vaccinated with the help of complex vaccines, which are used to develop in the child's body specific protection against certain diseases. The use of complex vaccines has an important disadvantage - in the event of an allergic reaction, it is rather difficult to establish a violation that led to the appearance of an allergy. To solve this problem, you can use "Diaskintest".
It should also be remembered that in some cases the use of "Diaskintest" is contraindicated:
- Children under the age of 1 year.
- In the case of an acute or chronic disease in the acute stage, if the symptoms of this disease are not similar to those of tuberculosis.
- In the case of somatic diseases in the acute stage.
- If there is any dermatological disease (in this case it will be quite difficult for the doctor to separate the symptoms of dermatological disease from allergic symptoms that appeared as a result of ingestion of the active components of Diaskintest into the body).
- In case of exacerbation of allergic diseases.
Test for adults
Diaskintest can be used to diagnose tuberculous infection in adults. The diagnostic method in this case will be standard - 0.1 ml of the drug is injected into an adult’s body, and after 3 days this person must visit the doctor to examine the injection site. After the injection, it is forbidden to wash the injection site with soap, detergents and other chemically active substances (however, you can wash the injection site with water). It is also forbidden to glue the place of injection with adhesive tape, wrap bandages, smear with creams and so on. The test is not done at the active stage of the disease.
Test for children
Diaskintest can also be used to diagnose tuberculosis in children if the child is older than 1 year. Most often, the sample is done at school or in kindergarten. The use of “Diaskintest” in children does not have any special features - for diagnosis it is necessary to introduce 0.1 ml of the drug into the child’s body, after 3 days you need to visit a doctor to decipher the test results, you can wash the injection site with clean water after injection, it’s forbidden to seal the place injection with a plaster and so on. It should be remembered that phenol is part of Diaskintest, however, the concentration of this substance in the medicine is so low that phenol is not capable of harming the child’s body.
Check the injection site need after 72 hours. Diagnosis is carried out by measuring papules with a ruler. In total there are three main reactions to the injection of "Diaskintest". Let's find out what the vaccination rate looks like, and also consider the cases when allergic reactions indicate that Koch's stick was infecting the body:
- Negative reaction In this case, the papule is completely absent, and the person has no reaction to allergies (although a small mark may remain from the injection, the diameter of which should be less than 2 mm). Such a reaction shows that a person is completely healthy. In some cases, due to an error of the doctor who performed the injection, a hematoma may appear at the injection site. It is important to understand that in some cases it is quite difficult to distinguish between a hematoma and a papule, so a person can be sent for an additional examination in order to completely eliminate the likelihood of infection of the body with a Koch sticks.
- Positive reaction. In this case, a papule forms at the injection site. Depending on the size of the papules, there is a weakly expressed reaction (when the diameter of the papule is less than 5 mm), a moderately pronounced reaction (when the diameter of the papule is 5-9 mm), a pronounced reaction (when the papule is 9-14 mm in diameter), and a hyperargic reaction (when the papule is more than 15 mm in diameter). The appearance of papules of any size indicates that a person is infected with Koch’s wand, and the size of the redness indicates the stage of development of the disease and the reproduction rate of Koch’s sticks (with the exception of the hyperergic reaction - in this case, the person needs additional diagnostics). With a positive Diaskintest, additional research is needed, after which the doctor should prescribe treatment. However, it should be understood that in some cases, infection of the body with a Koch bacillus does not always lead to the development of tuberculosis, since sometimes natural immunity can cope with this infectious agent on its own, which leads to recovery.
- Doubtful reaction. To make an accurate diagnosis, the papule must look very clear. But in some cases it makes sense to talk about a dubious reaction to the introduction of Diaskintest into the body. The main cases are reddening of the skin, a bruise, a thin mark, the formation of a very small papule, and so on. A doubtful or hyperergic reaction indicates that a person can be both infected and healthy, so additional diagnosis is necessary to confirm the diagnosis (although medical experience shows that the presence of doubtful reactions is more likely to indicate an infection in the body).
Positive reaction: necessary measures
A positive reaction to the D-test in an adult requires a serious examination. The patient is shown X-ray and laboratory diagnostics (including the Mantoux test). An x-ray of the lungs is prescribed to the child (radiation is less with it than with fluorography, and the pathologies of the lungs are better viewed). This is justified: for medical reasons X-ray is shown even to women in an interesting position.
In general, a positive result with Diaskintest is a pretext for registering a patient in a TB dispensary. In the future, he will have to go through a series of laboratory and clinical studies, and two months later, Diaskintest will be done again.
The composition of the test drugs
Diaskintest contains the synthetic antigens CFP10 and ESAT6, while the products of Koch's sticks are included in the Tuberculin composition.
Important! Not necessarily people infected with a tubercle bacillus, subsequently fall ill. Natural resistance to tuberculosis is characteristic of man. But there are so-called risk factors that contribute to the manifestation of the disease.
Composition Diaskintest and Tuberculin
Diaskintest's proteins are more specific than the active substances of tuberculin - the possibility of a negative reaction of the sample in the absence of tuberculosis is higher. Phenol is present in the formulation, but there is no cause for concern: with test reactions, its dose (0.25 mg) is not dangerous even for children.
Important! If Diaskintest showed a positive result in an adult, the size of the “button” does not play a role, the fact of its appearance itself is important.
As part of Diaskintest and Tuberculin there are no capable Koch sticks - it is impossible to get sick with tuberculosis after their introduction into the body. In addition, they do not lead to the development of immunity against tuberculosis, since they are not immunized. There are other useful information that patients usually do not attach importance to:
- sometimes observed malaise after the test is not dangerous. This is a reaction to foreign proteins,
- children are tested for tuberculosis at least once a year, as they are more susceptible to infection with Koch sticks. Adults (including pregnant women) are examined if they are registered in a TB dispensary or are regularly contacted in everyday life with people infected with tuberculosis,
- The protein contained in Diaskintest can trigger allergies. It will be a contraindication for further testing of DST,
- in the case of a positive Mantoux test, the introduction of Diaskintest is allowed for children from the age of one,
- children with Mantoux bend, but the negative result of Diaskintest is put under control. The introduction of a modern drug after two to three months is repeated,
- Diaskintest is a false negative in people suffering from immunodeficiency, serious chronic diseases.
Like many drugs, the diagnostic test has its side effects and contraindications. Diaskintest is not recommended for use in cases of:
- development of infectious diseases
- exacerbation of somatic diseases,
- acute manifestations of skin diseases,
- development of allergic reactions,
- manifestations of uncontrollable epileptic seizures.
There are no restrictions on the list of permissible foods. The drug is safe, but it is recommended to carry out the test during pregnancy. Lactation is not a relative contraindication. Diaskineste has few side effects, they include:
- slight temperature rise after injection,
- protein allergy (redness of the eyes, swelling of the mucous membrane of the nasopharynx, shortness of breath, itching),
- pressure jumps (in the elderly).
Important! With a positive Diaskintest in children conduct additional tests. It will allow to determine the activity of pathogens. In any case, the child is waiting for long-term treatment.
Modern means: pros and cons
If we compare the Mantoux and Diaskintest samples, we can note the advantages of an innovative tool, it is:
- highly sensitive
- gives you the opportunity to monitor the effectiveness of therapy.
A positive result with Diaskintest is noted when mycobacterium tuberculosis multiplies actively, allergic reactions rarely cause it. The drug practically does not give false positive reactions. This is very important, because a positive reaction in a child leads to the use of unsafe drugs. Mantoux test is not so specific. Положительной она бывает и при инфицировании микроорганизмами не туберкулезной природы, и при ярко выраженной иммунной реакции на БЦЖ.
Если пациенту делали Диаскинтест и у него проявилась «не туберкулезная» аллергия, симптомы обычно заметны сразу. Они исчезают до оценки тестовых показателей. DST is often administered with positive reactions to the Mantoux test - for the correct choice of therapy tactics. But you can not interchange them. These diagnostic tests complement each other.
D-test will not give a positive reaction when infected with “bullish” tuberculosis, and this variety is not uncommon in animal husbandry zones. That it is the basis of vaccination against tuberculosis. In addition, the practice shows that if a patient was given Diaskintest at the initial stage of infection, the reaction may be false negative. A similar picture is sometimes observed with exacerbation of tuberculosis. Experts recommend using the Mantoux test, and with questionable indications, test them with a more specific drug.
Profit screening is voluntary. Nobody can force a person to subject himself to this or that medical manipulation. But if you choose: Mantoux test and Diaskintest or tuberculosis with long-term therapy and relapse, the answer is predictable. Of course, the test and test - for the sake of their own health and the health of loved ones.
Side Effects of Diaskintest
- General malaise,
- A bruise or an abscess at the injection site
- Allergic reaction (urticaria, itchy skin all over the body, shortness of breath, redness of the eyes, swelling of the nasopharyngeal mucosa, etc.),
- Pressure jumps (especially for older people).
Side effects are usually short-lived and disappear within a few hours or days. If a severe allergic reaction develops, then antihistamines should be taken (Erius, Telfast, Zyrtec, Claritin, Fenistil, etc.). If an abscess appears in the injection area, an urgent need to seek medical attention, as this indicates that pathogenic bacteria have entered the wound and become infected.
In some cases, diaskintest can cause the so-called hyperergic (overly strong) reaction, which is manifested in the formation of a large papule (more than 15 mm in diameter), edema and irritation around the injection area, the formation of bubbles and pustules on the skin, and inflammation of the lymph nodes. This hyperergic reaction is considered conditionally positive, but can also be attributed to the side effects of the diaskintest.
What is dangerous diaskintest?
Theoretically, diaskintest is safe because it does not contain any components that are considered hazardous to health. However, since the solution contains protein molecules, the sample can cause allergic reactions, including violently flowing. It is in the development of a violent allergic reaction that the main danger of Diaskintest consists. If in the near future after the injection the eyes become red, itchy skin, the nasopharyngeal mucosa swells or blisters and severe swelling develop on the skin of any part of the body, this indicates a violent allergic reaction, and in that case you should consult a doctor.
Diaskintest and Mantu
Diaskintest and the Mantoux test are skin tests for early detection of tuberculosis, when a person may still have no characteristic symptoms of the disease. The Mantoux test is known and applied for a very long time, but Diaskintest is a new study. Both samples (Mantoux and Diaskine) are skin tests, that is, a preparation containing some substances to which the human body reacts is intradermally injected for their production.
Mantoux test contains tuberculin - a substance produced by mycobacteria in the process of life, and therefore when it is introduced into the body a positive reaction occurs in those people who have active tuberculosis. But, unfortunately, the Mantoux test gives a high percentage of false-positive results, since a positive reaction can be caused not by the presence of tuberculosis in humans, but by the BCG vaccine made in the past, allergies to tuberculin, etc. Diaskintest, unlike Mantoux, contains only proteins mycobacterium membranes, therefore, does not give a false-positive reaction to a BCG vaccine made in the past or an allergy in humans. That is, Diaskintest, unlike Mantoux, gives a smaller percentage of false-positive results and registers only the presence of mycobacteria in the body, and not allergies or passive immunity cells developed after BCG vaccination. As for the statement, testimony, contraindications and record of the results, the Mantoux test and Diaskintest are quite similar.
Despite certain advantages of the Diaskintest over the Mantoux test (greater accuracy with fewer false-positive results), this study still has its drawbacks. Thus, at the early stage of infection and the development of tuberculosis, Diaskintest gives a negative result, and the Mantoux test is positive. That is, the earliest stages of tuberculosis can be detected using the Mantoux test, and diaskintest is useless in such cases.
In principle, due to false negative results in the early stages of development of tuberculosis, Diaskintest does not displace the Mantoux test completely. Therefore, experienced doctors advise you to do both skin tests simultaneously on different hands.
If there is a Bend test Mantoux (large increase in the size of papules), then it is advisable to make a diaskintest. If diaskintest in this situation is negative, then it is recommended to repeat it after two months to make sure that the positive Mantoux is caused not by an early stage of tuberculosis, but by allergies or a BCG vaccination made in the past. But if, against the backdrop of a Mantoux diaskintest turn, it is positive, then this is evidence of infection with mycobacteria and, accordingly, an indication for preventive treatment.
Thus, it is obvious that the Mantoux test and Diaskintest have their own advantages and disadvantages, their results partially duplicate each other, and some of them do not, therefore, these tests are logical to be considered complementary, rather than competing. That is why, even knowing perfectly well all its imperfections, doctors still use the Mantoux test for the early diagnosis of tuberculosis in children, and diaskintest is used as an additional clarifying method.
Unfortunately, the disadvantage of the diaskintest is the fact that it often causes excessively strong reactions (hyperergic), which are also an indication for the subsequent complete and detailed examination in order to detect active tuberculosis. Hyperargic reaction to diaskintest can manifest as inflammation of the lymphatic vessels, the formation of bubbles or pustules on the skin. Such excessive reactions in diaskintest, according to researchers from the Mordovian State University. Ogarev, observed in 30% of cases, while the Mantoux test - only 1.5% of cases. This fact means that in identifying a hyperergic reaction to diaskintest, it should not be put in the future in order to avoid the development of skin test complications.
Details on the Mantoux trial
Preparation for Diaskintest
Diaskintest is advisable to plan before vaccinations, since if vaccination was performed, then after it you need to wait at least a month before testing for tuberculosis. And if diaskintest is carried out before vaccinations, then they (except for BCG) can be placed immediately after taking into account the result of a skin test, provided that its result is negative. But if the diaskintest is positive or doubtful, then any vaccinations can be put no earlier than six months.
If an adult or a child suffers from allergic reactions to any substances (food, medicine, plant pollen, etc.), then diaskintest should be done under the guise of taking antihistamines (Erius, Telfast, Fenistil, Parlazin, Cetrin, Claritin, etc.). It is recommended to take antihistamines for 7 days - 5 days before the test and two days after. That is, a person begins to take antihistamines, on the fifth day diaskintest is done, after which antihistamines are taken for two more days (in fact, before taking into account the results of the test).
Adults before staging Diaskintest should refrain from drinking alcohol for 2 to 3 days and further until the results are recorded. No other special training is required before the test. You can lead a normal life, eat your favorite foods, etc.
How to do diaskintest?
Diaskintest is done in a polyclinic, tuberculosis dispensary or in private centers involved in immunization (vaccination). For the test, the solution is injected strictly intracutaneously in the lower third of the inner surface of the forearm. And they try to use a non-working hand, that is, a left one for right-handers and a right hand for left-handers.
For statement diaskintest take disposable tuberculin syringes with thin needles and with an oblique cut. Before using syringes, the expiration date is checked. After preparing the syringes, the preparation is carried out To do this, the rubber stopper of the bottle with the diaskintez solution is wiped with gauze moistened with alcohol. Next, pierce the cork with a needle, pick up the solution in a syringe in the amount of 0.2 ml, remove the needle and replace it with a new one. After that, to remove the air, the syringe is held up with a needle and lightly tapped on its wall with a fingernail so that the bubbles detach from the walls and collect on the surface of the solution. Then, to remove this air, a part of the solution is released into a cotton swab so that 0.1 ml remains in the syringe.
A person is seated on a chair in a comfortable position, bare the forearm and wipe the skin of its inner surface with a cotton swab moistened with 70% alcohol. After that, dry the skin with a sterile cotton swab. Then, a needle is inserted into the skin of the lower third of the inner surface of the forearm with a 3–4 mm cut up. Before the introduction of the skin stretch, and the needle is inserted parallel to the skin surface. Then, pressing the piston from the syringe injected 0.1 ml of the solution strictly intradermally. At the injection site, a “lemon crust” with a diameter of 7–9 mm, colored white, forms on the skin.
The bottle after a set of the first dose of the solution is stored under sterile conditions for a maximum of two hours.
The result of Diaskintest is estimated after 72 hours (three days) after the test. To assess the result, the doctor or nurse inspects the injection site for papules (seals) or redness. Papule or redness is measured with a transparent ruler with millimeter divisions. The diameter of the papule formed and the redness around it is measured. If there is no papule, then the reddening diameter is measured. In this case, the result is considered doubtful if there is a reddening or papule with a diameter of 2-4 mm. A positive sample is considered when papules are larger than 5 mm. The result is considered hyperergic (with an overly strong reaction) in the presence of vesicles, necrosis, inflammation of the lymph nodes in the injection area, regardless of whether there is a papule. Moreover, hyperergic reaction also refers to positive. If at the injection site there is only a point from the injection, then the result of diaskintest is considered negative.
Is it possible to wet diaskintest?
Yes, the place of introduction of Diaskintest can be wetted. That is, after setting the skin test, it is allowed to bathe, but it is impossible to apply detergents directly to the injection site and rub it with a washcloth.
It should also be remembered that the place of the sample should not be rubbed with hands or any objects, scratched, sealed with a plaster, rewound with a bandage, smeared with green paint or other drugs, apply cosmetics and perfumes. To ensure that the sample site does not itch, it is recommended that you do not wear long-sleeved clothes made of skin-irritating tissues (for example, prickly or fleece wool, etc.) after its placement.
In addition, in order to avoid false positives, it is not recommended to bathe in the bath and sauna, sunbathe on the open beaches and in the solarium, swim in the pool and natural reservoirs, play sports for a long time after frost. Such recommendations are due to the fact that high and low ambient temperatures, perspiration, dirty water and dust can cause infection or irritation of the injection site, as a result of which a hyperergic or false positive reaction will develop.
What could be the results
The result of the diaskintest is estimated 72 hours after the injection of the solution and can be positive, negative or doubtful, depending on the type of injection site.
A negative result of Diaskintest is considered in the following cases:
- At the injection site there is no papule (compaction) or redness, and only the point from the injection is visible,
- At the injection site is visible the so-called "prick reaction" in the form of a bruise of 2 to 3 mm in diameter.
The doubtful result of Diaskintest is considered in the following case: at the injection site there is a redness of any size without papules (seals).
Diaskintest is considered to be a positive result in the following cases:
- At the injection site, there is only a papule (compaction) with / without reddening less than 5 mm in diameter (the reaction is mild positive),
- At the injection site there is a papule with or without redness with a diameter of 5–9 mm (the reaction is moderately positive),
- There is a papule at the injection site with or without reddening with a diameter of 10–15 mm (the reaction is pronounced positive),
- At the injection site, there is a papule more than 15 mm in diameter, or a papule of any size is combined with vesicles, ulcers, inflammation of any lymph nodes and lymphatic vessels (hyperergic, that is, sharply positive, excessively strong).
Diaskintest - normal, positive, negative
Normally, when a person is not sick with tuberculosis and is not infected with mycobacteria, the response to Diaskintest should be negative. Positive (including hyperergic) and doubtful reactions to diaskintest are abnormal, as they indicate the presence of mycobacteria in the human body. Positive and doubtful reactions are considered the basis for referring a child or an adult to a consultation with a phthisiatrician doctor for the purpose of additional examination for the detection of active tuberculosis.
This photograph shows a positive result from Diaskintest.
This photograph shows the hyperergic result of Diaskintest.
This photograph shows the dubious result of Diaskintest.
This photograph shows a negative result of a diaskintest in the form of a bruise.
This photograph shows a negative result of the diaskintest as an injection shot.
Diaskineste reaction by day
The diaskintest reaction by day is not significant, since the result should be evaluated only 72 hours after the injection - not earlier and not later. However, during the first hours after the test, redness and itching may occur, indicating an allergic reaction. Such manifestations of allergy usually disappear in 48–72 hours and, accordingly, do not interfere with the evaluation of the results of the test.
In addition, a reddening or papule may already be formed within the first or second day after the injection, becoming maximum in size and severity by the end of the third day. It is because of the maximum severity of the reaction three days after the injection, the test result is taken into account 72 hours after the injection of the solution. After 72 hours after diaskintest injection, all skin reactions will decrease to their complete disappearance.
Bruise in the area of diaskintest
A bruise in the area of diaskintest may occur in some cases, but such a reaction is considered a variant of the norm. A bruise usually occurs as a result of damage to a blood vessel and leakage of a small amount of blood intracutaneously. A large bruise can interfere with the correct recording of the result of the diaskintest, so in such a situation, the doctor may suggest that the test be repeated after some time.
If diaskintest is positive in a child or adult
A positive and dubious result of diaskintest indicates that the person is infected with mycobacteria. But at the same time, positive or dubious results do not make it possible to distinguish between what is happening in a particular case - active tuberculosis or just infection (which is recorded in 90% of the adult population of Russia) when the person is healthy and the disease does not exist. That is why, in case of a positive or doubtful result of a diaskintest, an adult or a child must be sent for consultation to a TB doctor who is engaged in the treatment and diagnosis of tuberculosis.
The TB doctor prescribes a comprehensive examination, which is necessary to distinguish active tuberculosis from infection. As part of the survey, an X-ray / computed tomography (depending on the capacity of the institution) of the chest, complete blood count and urine analysis, and bacteriological urine culture are required. If a person coughs, sputum research is also conducted (bacteriological culture and microscopy). Дополнительно могут назначаться УЗИ лимфатических узлов и внутренних органов.
Если в результате обследования у взрослого или ребенка выявляется активный туберкулез любых органов (легких, почек, внутригрудных лимфатических узлов, костей и т.д.), то врач проводит лечение инфекционного заболевания согласно утвержденным Минздравом протоколам. For treatment, antibiotics are prescribed, which must be taken according to the scheme indicated by the doctor, within a few months.
If, with a positive result of diaskintest, a survey did not reveal active tuberculosis, then the person is considered infected with mycobacteria. This condition is currently called latent tuberculosis infection (as defined by WHO), and although a person in this state does not suffer from tuberculosis, it is not dangerous to others, as it does not release mycobacteria into the environment, however, the federal recommendations of the main TB doctor in Russia say that it is necessary to carry out preventive treatment with anti-TB antibiotics. The goal of prophylactic treatment is to reduce the risk of developing active tuberculosis in an infected person in the future.
If a person refuses prophylactic treatment, then he will be put on record at the tuberculosis dispensary and will diaskintest periodically (once every 3–6 months). Most often in similar cases in the next one and a half years diaskintest becomes negative, and this indicates that the body completely suppressed the activity of mycobacteria, and now the person is healthy. However, if the diaskintest remains positive for one and a half years, this indicates that mycobacteria are not suppressed, and in this case, although the person does not have tuberculosis, he is at high risk of developing this infection. When diaskintest remains positive for 1.5 years of follow-up at a tuberculosis dispensary, the doctor will again recommend undergoing a course of prophylactic antibiotic treatment.
Alternative to diaskintest
An alternative to diaskintest as a diagnostic method for tuberculosis is the quantiferon test and the T-spot test, which are also based on determining the body's response to the introduction of mycobacterial proteins. But during the implementation of the quantiferone and T-spot test, it is not intracutaneous administration of proteins, but blood is taken, and the whole reaction is carried out in a test tube.
Diaskintest - reviews
Most of the reviews on diaskintest (90% or more) are positive, since this test allowed parents to identify or eliminate tuberculosis in children, which was suspected based on a positive (bad) Mantoux. In the reviews, it is noted that Diaskintest makes it possible to understand whether there is an active tuberculous process in the body or a positive Mantoux test is due to the allergy / response to the BCG vaccination. In addition, parents indicate that Diaskintest has allowed them to find peace with the child’s health or to detect tuberculosis at an early stage.
There are few negative reviews about diaskintest and they are mainly due to severe adverse reactions in response to the drug administration.
What is the test of Diaxintest, what are its advantages?
Diaxintest technique appeared and became widespread due to the fact that the Mantoux test reaction is sensitive to two mycobacterial subspecies - bovine and human. In rural areas, in pastoral areas, a “bullish” strain of tuberculosis is common. You can become infected through fresh milk, which often drink not boiled. Therefore, for a more accurate determination of the human subtype of mycobacteria, a test for diaksintest tuberculosis appeared.
The sensitivity of Diaxintest is 90%, while the sensitivity of the Mantoux test is no more than 50%. Sample Diaskintest makes it possible to determine whether a person is infected with tuberculosis or not while the disease is in a latent form.
What does Diaxintest consist of?
- synthetic antigens: CFP10 and ESAT6. In the pathogens of tuberculosis, too, there are these proteins. If the patient is infected or has tuberculosis, then a reaction to Diaxintest occurs.
- sodium and potassium salts
- sodium chloride,
- preservative phenol
- polysorbate stabilizer.
The dose of phenol is 0.25 mg, and is safe for both adults and children.
The drug was developed in Russia, produced here.
Indications for Diaskintest
Diaskintest drug is used to detect tuberculosis in the following cases:
- preventive examination,
- assessment of the dynamics of the process in patients undergoing treatment for tuberculosis: the response to the test is reduced to negative in the event of a cure,
- to exclude tuberculosis in case of diseases of other diseases,
- to rule out tuberculosis after BCG vaccination. The fact is, the Mantoux reaction after this vaccination is not informative, usually shows a positive result,
Diaxintest and Mantoux test are not interchangeable.
Phthisiatricians use Diaxintest after a positive Mantoux reaction to clarify the result.
Disadvantages of Diaskintest Sample
- Diaskintest is insensitive to pathogens of cow tuberculosis. The BCG vaccine contains these pathogens in a weakened form. Therefore, with the help of Diaxintest, it is impossible to understand whether a child should have a BCG again at the age of seven or not. Diaskintest for children up to seven years old is held only after or at the same time as Mantoux.
- Diaskintest is falsely negative at the beginning of the disease, when the pathogen has entered the body, but has not yet begun to multiply actively. The test is repeated after two or three months.
- Diaxintest is also falsely negative in severe forms of tuberculosis, and in weakened people. In these cases, the body is already so weak that it does not fight the pathogen.
therefore less sensitive Mantoux test still actively used in tuberculosis diagnostics. There are cases when the patient is simultaneously put a Mantoux test on one hand and Diaxintest on the other.
In which institutions can do diaskintest?
Diaskintest can be done:
- in child care facilities
- in tuberculosis dispensaries,
- in tuberculosis centers.
Special attention to children's institutions is due to the fact that children and adolescents are primarily at risk.
Adults are examined if they come in contact with infected people, for example, someone from a family member has tuberculosis and contact cannot be avoided. Or if they are composed registered with the tuberculosis dispensary. Patients with diabetes must do Diaskintest. The entire diagnostic complex is carried out for children who come in contact with infected people: Mantoux test reaction, Diaskintest, chest X-ray.
Interpretation of the Diaskintest result
The result of Diaskintest is checked after 72 hours.
As a rule, use a transparent ruler. Redness is measured or papules diagonally.
- If at the injection site only a trace of the injection is visible, then the result of Diaskintest is negative. Thus, the norm is the absence of redness or papules.
- If the skin turns red, but there are no papules, Diaskintest is doubtful. No matter how big the redness is, what matters is it.
- If there is a papule, the result is positive.
In turn, papule size divided into the following categories: poor response (up to 5 mm), moderate reaction (up to 9 mm), severe reaction (more than 10 mm). The division is rather conditional, but this information is used later when the patient is undergoing treatment, and the results of previous tests are compared with subsequent results.
A papule of 15 mm or more may be formed. Inflammation of the skin around it may also occur. Then they talk about hyperergic reaction to Diaskintest.
All patients with a positive, questionable test result and a hyperergic reaction to Diaskintest are sent for further examination with the advice of a specialist. Standard examination includes: Mantoux test, X-ray, urine and blood tests. This rule applies to both children and adults.
There is such an interesting fact. Fluorography or X-rays are often visible education - Calcinates or Gon foci. This means that the patient was infected, but his immunity allowed the body to cope with mycobacteria of tuberculosis. The disease as such has not come, and immunity has developed. In these cases, the Mantoux reaction is either positive or doubtful.
What mode to follow after the sample Diaskintest
- It is forbidden to wash with soap and shower gels, although you can wet the place where the sample is placed,
- it is forbidden to comb the injection site,
- Do not use plaster or bandage.
If you do not follow the above recommendations, the skin will turn red and it will be impossible to evaluate the test result.
You can eat and drink anything, except for alcohol intake by adult patients. Reactions in which the products of alcohol metabolism in the body can cause redness at the injection site, and an accurate assessment of the result will also be impossible.
Now that it has become more clear what Diaskintest is, let's turn to the opinion of the doctors.
According to reviews of many phthisiatricians, Diaskintest makes it possible in most cases to almost accurately determine the presence of mycobacterium tuberculosis in the body and begin treatment. While fluorography shows an existing disease, the Mantoux test has a very high degree of error and is not informative if the patient has acquired anti-tuberculosis immunity.