Diagnosis

If your doctor suspects there is something wrong and that it is not just a cold, you may be referred to an outpatient department for people with lung diseases or to an X-ray department. The chest x-ray examination is the most important test. If changes in the lungs can be seen, a sample of sputum will be sent for microscopic examination and culture. Culture of tuberculosis bacteria will take 4-12 weeks. Because of this, it takes some time before an accurate diagnosis is possible.

Quicker methods using DNA techniques are under development, and a TB skin test is available. A small amount of testing fluid (called tuberculin) is injected just under the skin on the lower part of your arm. After 2 or 3 days, the health care worker will measure your reaction to the test. You may have a small bump where the tuberculin was injected. The health care worker will tell you if your reaction to the test is positive or negative.