Acid-fast Bacilli culture & smear test is one of the TB culture and sensitivity tests where the Mycobacterial infection is diagnosed on the blood sample. It is divided into two parts and if one is positive or anyone is positive then to know the complete infection the second one is done. However, in most of the cases first, the smear test is done followed by the culture blood test. It is prescribed when a person is having the symptoms of lingering, chronic cough that produces phlegm or sputum, sometimes with bloody streaks, fever, chills, unexplained weight loss and chest pain.