Extensively drug-resistant tuberculosis

Extensively drug-resistant tuberculosis
Description of extensively drug-resistant tuberculosis
SpecialtyInfectious diseases 
SymptomsThe same as tuberculosis
CausesMycobacterium tuberculosis
Risk factorsImproperly treated tuberculosis

Extensively drug-resistant tuberculosis (XDR-TB) is a form of tuberculosis caused by bacteria that are resistant to some of the most effective anti-TB drugs. XDR-TB strains have arisen after the mismanagement of individuals with multidrug-resistant TB (MDR-TB).

Almost one in four people in the world is infected with TB bacteria.[1] Only when the bacteria become active do people become ill with TB. Bacteria become active as a result of anything that can reduce the person's immunity, such as HIV, advancing age, or some medical conditions. TB can usually be treated with a course of four standard, or first-line, anti-TB drugs (i.e., isoniazid, rifampin and any fluoroquinolone). If these drugs are misused or mismanaged, multidrug-resistant TB (MDR-TB) can develop. MDR-TB takes longer to treat with second-line drugs (i.e., amikacin, kanamycin, or capreomycin), which are more expensive and have more side-effects. XDR-TB can develop when these second-line drugs are also misused or mismanaged and become ineffective. The World Health Organization (WHO) defines XDR-TB as MDR-TB that is resistant to at least one fluoroquinolone and a second-line injectable drug (amikacin, capreomycin, or kanamycin).[2]

XDR-TB raises concerns of a future TB epidemic with restricted treatment options, and jeopardizes the major gains made in TB control and progress on reducing TB deaths among people living with HIV/AIDS. It is therefore vital that TB control be managed properly and new tools developed to prevent, treat and diagnose the disease.

The true scale of XDR-TB is unknown as many countries lack the necessary equipment and capacity to accurately diagnose it. By June 2008, 49 countries had confirmed cases of XDR-TB.[3] By the end of 2017, 127 WHO Member States reported a total of 10,800 cases of XDR-TB, and 8.5% of cases of MDR-TB in 2017 were estimated to have been XDR-TB.[2]

In August 2019, the Food and Drug Administration (FDA) approved the use of pretomanid in combination with bedaquiline and linezolid for treating a limited and specific population of adult patients with extensively drug resistant, treatment-intolerant or nonresponsive multidrug resistant pulmonary TB.[4]

  1. ^ Houben, Rein M. G. J.; Dodd, Peter J. (25 October 2016). Metcalfe, John Z. (ed.). "The Global Burden of Latent Tuberculosis Infection: A Re-estimation Using Mathematical Modelling". PLOS Medicine. 13 (10): e1002152. doi:10.1371/journal.pmed.1002152. ISSN 1549-1676. PMC 5079585. PMID 27780211.
  2. ^ a b Cite error: The named reference :0 was invoked but never defined (see the help page).
  3. ^ World Health Organization (2008). "Countries with XDR-TB confirmed cases as of June 2008" [1]
  4. ^ "FDA approves new drug for treatment-resistant forms of tuberculosis that affects the lungs" (Press release). Food and Drug Administration (FDA). 14 August 2019. Archived from the original on August 16, 2019. Retrieved 18 August 2019.
This article is issued from Wikipedia. The text is available under Creative Commons Attribution-Share Alike 4.0 unless otherwise noted. Additional terms may apply for the media files.