Essay On Tb Skin Test

There are four available tests to diagnosis TB. These are skin test, sputum test, blood test and imaging test.

The TB skin test

The TB skin test [8, 9] is a widely used diagnostic TB test, and sometimes it is used to verify for latent TB infection. The TB skin test involves injecting a small amount of fluid called tuberculin into the skin in the lower part of the arm. Then the person must return after 3 to 4 days to have a trained health care worker look at their arm. The health care worker will look for a raised hard area or swelling, and if there is one then they will measure its size. They will not include any general area of redness. The TB skin test result depends on the size of the raised hard area or swelling, and the larger the size of the affected area the greater the likelihood that the person has been infected with TB bacteria at some time in the past. But interpreting the TB skin test result, that is whether it is a positive result, may also involve considering the lifestyle factors of the person being tested for TB. The TB skin test also cannot tell if the person has latent TB or active TB disease. False positive results happen with the TB skin test because the person has been infected with a different type of bacteria, rather than the one that causes TB. It can also happen

Chest X-rays are valuable for predicting pulmonary lesions of tuberculosis. In primary infection of TB, an X-ray will show an abnormality in the mid and lower lung fields. In this case lymph nodes may be enlarged. Reactivated TB bacteria usually infiltrate the upper lobes of the lungs. X-Ray changes the characteristics of active TB. The main disadvantage of using X-Ray frequently is the radiation used in X-Ray sometimes damage the body cells, DNA structure which leads to cancer. Figure 3 shows the X-Ray images of the chest, where lung is affected by TB. In Figure 3, two arrows are