Culture for M. tuberculosis confirms a TB diagnosis and is the most sensitive diagnostic method.(Ref.)
Both solid and liquid cultures can be used. Liquid cultures deliver quicker results (10-14 days vs. 2-3 months) and have higher sensitivity. However, they are more costly and require a higher degree of laboratory capability.
All culture testing is performed by specialized TB laboratories and may not be available in all areas. Request cultures for patients with negative smear and Xpert MTB/RIF results and a strong suspicion of TB; however, treatment should not be deferred while waiting for the results.