Tuberculosis (TB) is and infectious disease with a high mortality and is a great challenge for public health worldwile. Among the problems for its eradication, diagnosis represents a major challenge, particularly in low and middle income countries. The Xpert MTB/RIF is an almost completely automated molecular test; it yields a rapid diagnosis and screens for the presence of rifampin resistance, permitting an early and efficient treatment. However, it has a low sensitivity in patients with paucibacillary disease, and false positives for rifampin resistance and TB in patients with past medical history of TB have been reported. That’s why Xpert MTB/RIF Ultra was developed, which has an improved sensitivity for the diagnosis of tuberculosis, especially in paucibacillary cases, and a decrease in false positives for rifampicin resistance; Nowadays it is the most recommended molecular test by the WHO, hoping to reduce the time to diagnosis and treatment.

This review article analyzes the challenges of improving the diagnosis of tuberculosis, the characteristics and performance of Xpert MTB / RIF and Xpert MTB / RIF Ultra for pulmonary and extrapulmonary forms and for the detection of rifampicin resistance.