Mantoux or x-ray: which is better, safer?
The rise in the incidence of tuberculosis is still relevant for many regions of the country. Therefore, great attention modern medicine has paid to identification of infection of tubercle bacilli, and the diagnosis of early forms of the disease. In adult patients this is done through preventive x-ray studies overview of x-ray of the lungs, sputum smear, CT.
As in children x-ray diagnosis is carried out only under strict indications, in this case, we recommend conducting a tuberculin skin test (Mantoux). Many parents are often interested in the question: how safe is the Mantoux test or x-ray that is more informative, better or more harmful? For starters, consider both the type of diagnosis.
The Mantoux test has several disadvantages:
- The magnitude of the injection spot is largely dependent on the reactivity of the organism of the child. If the patient allergic history, potential rapid response and large spot diameters exceeding 5 mm. Weakened immune system, even in the presence of infection of tubercle bacilli, it may cause the result of the Mantoux test will be evaluated as negative.
- It is necessary to carry out a Mantoux test. Well, if it is made in a specialized TB facility. But often it is conducted in children’s hospitals, where the staff has bad technique. Also won’t damage or RUB the injection site for 2-3 days, this condition is not always observed by the children. As a result, false positive or false negative reaction.
- The Allergy of the body. Despite the fact that tuberculin is injected in small amounts, in children with a certain predisposition, you may experience various negative consequences of such a diagnosis: urticaria, bronchospasm, in severe cases, anaphylactic shock.
- The low specificity of the method. A positive reaction was also observed after the conducted BCG, infection non-pathogenic forms of the tubercle Bacillus.
According to medical experts, the informativeness of tuberculin skin test less than 50%. However, the method still finds use because of its availability, cheapness, ease of application.
X-rays in children is used only on strict indications. For the purposes of routine inspection, for example, to detect tuberculosis, it is not used. This is due to the negative impact of ionizing radiation on growing children’s bodies. The younger the child, the more harmful and dangerous for him x-rays.
Another thing, if the patient has clinical manifestations of tuberculosis, strongly positive Mantoux, additional data from other studies (tubercle bacilli in the sputum, antibodies to TB in blood), and it is vital to confirm the presence of a tuberculosis outbreak. In this case, conduct x-rays of the lungs; or of a backbone, bones of extremities with extrapulmonary forms of the disease.
To minimize the effect of ionizing radiation on the organism of the child, it is better to perform x-rays on a digital camera, with the mandatory use of protective equipment (lead apron, protection of the thyroid gland and the genital organs).
Thus, to compare such diagnostic methods as the Mantoux test and x-rays is not entirely correct. Tuberculin skin test screening refers to diagnostic techniques, it is not always accurate, but available to all segments of the population. X-rays do on strict conditions, after a medical examination, and conduct all the necessary research when it is important to confirm the presence of a tuberculosis outbreak.
However, medical science does not stand still. And today there are modern screening methods of diagnosis of tuberculosis. Such is Diaskintest. Its procedure is similar to the Mantoux test, but introduces a synthetic protein, the same as in the tubercle Bacillus. This ensures the diagnostic accuracy and significantly reduces the likelihood of allergic reactions.
You can also get a PCR screening for the presence of tubercle bacilli in the body. There are methods of detection of antibodies to TB in blood. In any case, to determine the choice of diagnostic method will help the pediatrician observe the child. It takes into account the dynamics of the patient, the presence or absence of clinical evidence for tuberculosis, the results of laboratory examinations (blood, sputum, urine), and only then recommends a more specific diagnosis.