Conventional and Molecular Diagnosis of Drug-Sensitive and Drug-Resistant Pulmonary Tuberculosis

Tuberculosis is a transmissible disease, which is primarily caused by the bacteria Mycobacterium tuberculosis and by other Mycobacterium species, forming the Mycobacterium tuberculosis complex. Until the end of the 20th Century, most cases of pulmonary tuberculosis were considered curable. Nevertheless, the rising of tuberculosis resistant to firstand second-line anti-tuberculous drugs is threatening the world’s tuberculosis control programs. Due to this fact, the World Health Organization and other public health institutions recommended applying the conventional methods, affordable by low-incoming countries, to diagnose tuberculosis and to develop faster and more sensitive and specific methods to identifyM. tuberculosis and determine their condition of anti-tuberculous drug resistance or drug sensitivity. In this chapter, we mention the most used conventional and molecular methods designed to identify M. tuberculosis and to determine their drug sensitivity or drug resistance. We also briefly describe the fundamentals of methods and its advantages and limitations.