Reaction the skin test is evaluated strictly in 72 hours after tuberculin injection, and estimates the health worker. Try to check that the measurements of the samples were produced on time.
The measurement is performed with a ruler, positioning it perpendicular to the axis of the forearm. So measure the size of the papule – swelling of the skin in the area of injection of tuberculin. If the papule is absent, estimate the reddening of the skin (hyperemia).
Negative reaction the skin test is called a complete lack of any response of the body, respectively, in the injection is only from the injectors. The dubious result is a papule with a diameter of 2-4 mm or only hyperemia. The reaction of 5 mm or more having a positive reaction, if the size of the papule is greater than 17 mm, then such reaction is called a hyperergic.
Usually in children vaccinated against tuberculosis in the hospital, the first 5 years there is a positive reaction of Mantu, which fades over time. If it is negative, it indicates that the vaccination was ineffective in this case, vaccination must be repeated.
Hyperergic reaction, swollen lymph nodes, a red mark from the sample test to the elbow, and the appearance of bubbles in the area of sample introduction can attest to the fact that there was an infection with Mycobacterium tuberculosis. If your child has such a reaction, contact your TB doctor, he will appreciate it, is the true response or the false, will appoint the necessary additional examination.
Advice 2: On what day of the Mantoux test
Mantoux test was created to diagnose TB infection, which explains the procedures for samples every six months among children up to graduation.
Mantoux test is compulsory for all children aged one year to 18 years. If the child is not vaccinated with BCG vaccine, it is necessary to put the sample two times per year. The sample is made only by employees of the national health system trained in the TB dispensary.
Mantoux test is carried out with restrictions: it cannot be conducted at home or during quarantine for infectious diseases. Between the sample and test any preventive vaccine should pass one month. Exactly the same time you must wait after the child's recovery from any acute disease. Before the audition, each child receives a General physical examination.
Evaluation of Mantoux test
Capsules filled with Mantoux test tuberculin – allergen, unable to cause tuberculosis. However, reactions of the child's body for this test, the doctor can draw some conclusions. This explains the need for re-examination after the test.
While technically correct introduction of the allergen under the skin on its surface acts as a "lemon crust". In case of positive reaction it is replaced by the characteristic papule that looks like a normal mosquito bite.
Mantoux test is assessed 72 hours after injection. The doctor measures the size of papules by using a transparent ruler with millimeter divisions. He also measures the size of the infiltration in cross section. In the absence of papules recorded hyperemia.
negative reaction okolocha size of 1-2 mm;
- suspicious reaction is diagnosed when an infiltrate the size of 2-4 mm;
- positive reaction is diagnosed when infiltration size of 5mm or more;
- there is also the risk of the child giperergicakie reactions to the Mantoux test with a size of 17 mm and more.
If the child was vaccinated with BCG vaccine, the first 4-5 years of his life he will always be fixed firmly positive reaction greater than 5 mm, but not more than 16 mm. With age it gradually fades away. This phenomenon is considered perfectly normal and is called "post-vaccination Allergy.
However, there are other responses of the child's body, which suggests suspicions of the ineffectiveness of vaccination and re-execution. But the alarm when the PPD is accompanied by the appearance of vesicles or swollen lymph nodes. All these signs point to the fact the child transmission of the causative agent of tuberculosis.
Please note the contraindications for Mantoux test: skin diseases, epilepsy, exacerbation of chronic diseases, an Allergy, individual intolerance to the components of the sample.
In order to reduce the risk of false-positive reactions, make sure to drenched the area of the injection on the first day and not combed it.