After 48 to 72 hours, the arm is examined, and a positive test will show up as a red welt on the arm. For example, those who have been previosuly exposed will test positive, and so will people who have been exposed to other related mycobacteria. But, this can be difficult because TB can appear to be pneumonia, lung abcesses, etc.
Sputum is also very crucial in the diagnosis.
Samples of sputum will help determine which drugs will work against a confirmed diagnosis and the particular strain that the person has. Due to the Mycobacteria 's slow growth, four weeks are needed for a diagnosis. That is only if the TB is not resistant to the drugs. This treatment is called short-course chemotherapy . Treatment for active TB involves taking several anti-TB drugs for 6 to 9 months, and during that time confinement may be necessary.