Tuberculosis is an infectious disease that is difficult to cure. The disease is easier to prevent, therefore, preventive measures and timely diagnostics are important components in the fight with a tubercle bacillus. What is Diaskintest and what role it plays in modern diagnostics - this is the subject of this article.
Methods for diagnosis of tuberculosis
Mycobacterium tuberculosis or a stick Koch is a very ancient bacterium, in the old days the disease caused by this bacterium was called "consumption" from the word "wither". The illness spared no one: neither the poor nor the rich. It is known that in the study of the Egyptian pyramids, traces of the disease in severe form were found in 6 out of 10 mummies of the pharaohs. Koch's wand is very stable in the external environment. The disease itself, tuberculosis is transmitted by airborne droplets when coughing, sneezing, talking with a patient with an open form.
In the modern world, the mycobacterium also mercilessly destroys people and every year the statistics of the disease increases. An important aspect in early detection, which helps to conduct treatment more effectively, is the diagnosis of tuberculosis. To date, the diagnostic methods are as follows:
- Visual inspection, identification of complaints.
- Radiography ( fluorography ) - performed in 2 angles. The method allows you to see whether the lungs are affected or not.
- Computer tomography - a modern method accurately shows the localization of the tuberculous process in the lungs.
- Bacteriological culture of sputum is a very informative method, but takes a long time, the active growth of bacteria begins on the 20th - 60th day. Sowing helps to determine the sensitivity of bacteria to antibacterial and anti-tuberculosis drugs, which is very important for the treatment process.
- Studies of blood and urine are of little informative and are used in combination with other methods.
- Cumulative tests can reveal the sensitization (sensitivity) of the body to the mycobacterium tuberculosis, they include:
- Tuberculin test - known as the Mantoux reaction ;
- graded test Pirke (practically not used because of low informativeness);
- test for tuberculosis Diaskintest.
Mantoux or Diascintest?
In order to prevent the development of the disease in children, every year, in general educational institutions, health workers diagnose with the introduction of subcutaneously Tuberculin, which is tuberculoprotein - a specific filtrate obtained from heat-killed mycobacteria of bovine and human tuberculosis. Tuberculosis test - Mantoux reaction, proceeds according to the type of allergic reaction, causing inflammation and the formation of papules at the site of administration.
Diaskintest is a new word in the diagnosis of tuberculosis. What drug should I prefer? Are there differences and what are the advantages of this or that method of diagnosis? To understand this, we need to consider the features of both methods:
- Tuberculin is a natural preparation that causes a specific allergic reaction. The Mantoux test is evaluated after 72 hours. The disadvantages of the method are frequent false positive reactions, which do not necessarily indicate the presence of mycobacterium in the body. High toxicity of the drug is also a drawback.
- What is Diaskintest in contrast to Tuberculin? This is a synthetic drug. The method of administration is the same as for Tuberculin, the sample is also evaluated after 72 hours. An allergic reaction occurs only in the case of activity of only mycobacterium tuberculosis in the body in case of disease or primary infection, which does not necessarily pass into the disease. For other mycobacteria that do not cause tuberculosis, there will be no reaction in the form of edema and papules, in contrast to tuberculin.
Diaskintest - composition of the preparation
When choosing a method for diagnosing tuberculosis with a new method, parents have regular questions: what is a Diaskintest drug, what is its composition, can it be carried out for a small child for diagnosis? If we look more closely at Diaskintest, the composition of the preparation at the rate of 0.1 ml is as follows:
- recombinant protein CFP 10-ESAT6 - 0.2 μg - the main active substance;
- potassium phosphate monosubstituted;
- sodium dihydrogen phosphate;
- sodium chloride;
- phenol;
- polysorbate 80;
- water for injections.
How do Diaskintest?
A test of Diaskintest for tuberculosis for diagnosis is prescribed by a doctor from the age of one year. The procedure should be specially trained nurse or paramedic who have an admission to this test. Used tuberculin syringes with thin short needles having oblique cut. Important! Before the introduction of the drug, the release date and the expiry date must be checked.
Technique of the procedure. The patient sits down, then the surface of the forearm is treated with an aseptic solution (70% ethyl alcohol), then the upper layer of the skin is drawn and parallel to its surface, the nurse injects 0.1 ml of the drug. Visually, a papule of a whitish color (7-10 mm) is formed in the skin. After a diaskintest, the patient's condition is observed for 10 minutes, in order to avoid complications.
Is it possible to wet Diaskintest?
The Diaskintest test that replaced Mantoux is more advanced, but the rules are the same. The site of vaccination should be kept dry for 72 hours, contact with water can provoke infection and enhance allergic reaction. If the vaccine is still wet, this should be told to the doctor. If there is a severe hyperemia after contact with water, the doctor prescribes a re-diagnosis to obtain a reliable result.
Diaskintest - evaluation of results
What is Diaskintest in terms of positive or negative evaluation of the results, what indicators are taken into account in the diagnosis? The result of the test is estimated after 3 days (72 hours). A doctor or nurse uses a transparent ruler to measure the transverse dimension of hyperemia and infiltration, if any. Hyperemia is only considered if there is no infiltrate. When the Diaskintest is conducted, the result is evaluated based on the criteria prescribed by the Ministry of Health and is entered in the medical examination sheet.
Diaskintest is the norm
Diaskintest - the norm in children or the indicator of well-being and absence of tuberculous mycobacterium in the body is the absence of reaction after the diagnosis. If after 72 hours the reaction is negative, then there is no active process of disease or infection with a tubercle bacillus in the body, therefore additional diagnosis by a doctor is not assigned, the child can attend general educational institutions.
Negative Diaskintest
The test for tuberculosis with the use of Diaskintest is very informative, its accuracy is 90%. With a negative test, there is no infiltration and hyperemia at the injection site, but in some cases, the effect of lemon crust may be observed, as a knock-off reaction with a size of no more than 2 mm. Doubtful reaction (false positive result) - hyperemia is not considered normal, the doctor is assigned either additional diagnostics, or repeated introduction of Diaskintest after some time.
Positive Diascintest
The presence of a tubercle bacillus in the body shows a change in the skin at the injection site: there is severe hyperemia and infiltration. Positive Diascintest in a child is evaluated according to the following parameters:
- positive reaction - infiltrate (papule) of any size;
- a weak positive reaction - a papule up to 5 mm;
- moderate positive - papules up to 9 mm;
- expressed - 10 - 14 mm;
- hyperergic - from 15 mm.
Diaskintest - side effects
The human body is individual, therefore to say that, there will be no side effects - it is impossible. The drug Diaskintest is low-toxic and rarely causes side effects on the body, but they are:
- subfebrile temperature in the evenings;
- allergic reactions (swelling of the nasopharyngeal mucosa, dyspnea, reddening of the sclera of the eye, itching at the injection site, rarely throughout the body);
- moderate intensity of headache;
- in adults, pressure changes may occur;
- Hyperergic reaction is an overly sensitized reaction to Diaskintest, occurs with individual hypersensitivity to the components of the drug. Physiologically manifested in the formation of an infiltrate more than 15 mm, the skin is inflamed, ulcers are formed, lymph nodes of the neck, armpits become inflamed. Hyperergic reaction may be an indicator of the activity of the tuberculous process in the body, so differential diagnostics is needed.
Diaskintest - contraindications
Any drug has contraindications and Diaskintest is no exception. Diagnosis of the drug is contraindicated in the following cases:
- during quarantine in general educational institutions;
- after the transferred diseases within 3 months;
- weakened immunity;
- infectious and viral diseases;
- epilepsy in the anamnesis;
- with increased sensitivity to the drug Diaskintest child or adult is not set;
- skin diseases in the stage of exacerbation (psoriasis, atopic dermatitis ).
Diascintest for adults
Tests for tuberculosis Diaskintest adults are prescribed after questionable results of fluorography, poor analysis and specific symptoms (cough, inflammation of the lymph nodes) as an additional element of diagnosis. At the results, the size of the papule does not play a decisive role, if it exists, it already indicates that contact with the mycobacterium of tuberculosis has taken place and the organism is either in the active stage of the disease or recently infected.