Extensively drug-resistant tuberculosis

Extensively drug-resistant tuberculosis (XDR-TB) is a form of tuberculosis that is resistant to at least four of the core anti-TB drugs. XDR-TB arises when drug-resistant TB does not receive proper treatment, leading to further resistance.

Definition

The World Health Organization (WHO) defines XDR-TB as TB that is resistant to isoniazid and rifampicin, the two most powerful anti-TB drugs, as well as any fluoroquinolone and at least one of three injectable second-line drugs (i.e., amikacin, kanamycin, or capreomycin).

Epidemiology

XDR-TB has been identified in 117 countries worldwide. The highest rates are found in Eastern Europe and Central Asia. In 2019, there were an estimated 484,000 new cases of multidrug-resistant TB (MDR-TB) and XDR-TB.

Treatment

Treatment for XDR-TB is lengthy, expensive, and has many side effects. The drugs used are not as effective as the first-line drugs for TB, and patients often need to take them for up to two years. In addition, patients often need extensive support and monitoring to help them adhere to treatment.

Prevention

Preventing the spread of XDR-TB involves improving the detection and treatment of drug-resistant TB. This includes strengthening TB control programs, ensuring access to quality-assured TB drugs, and improving infection control in healthcare settings.

See also

• Multidrug-resistant tuberculosis
• Tuberculosis management
• Tuberculosis treatment