Totally drug-resistant tuberculosis (TDR-TB) is a generic term for

tuberculosis Tuberculosis (TB) is an infectious disease usually caused by '' Mycobacterium tuberculosis'' (MTB) bacteria. Tuberculosis generally affects the lungs, but it can also affect other parts of the body. Most infections show no symptoms, in ...

strains that are resistant to a wider range of drugs than strains classified as

extensively drug-resistant 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-resis ...

. Extensively drug resistant tuberculosis is tuberculosis that is resistant to

isoniazid Isoniazid, also known as isonicotinic acid hydrazide (INH), is an antibiotic used for the treatment of tuberculosis. For active tuberculosis it is often used together with rifampicin, pyrazinamide, and either streptomycin or ethambutol. For l ...

and

rifampicin Rifampicin, also known as rifampin, is an ansamycin antibiotic used to treat several types of bacterial infections, including tuberculosis (TB), mycobacterium avium complex, ''Mycobacterium avium'' complex, leprosy, and Legionnaires’ disease. ...

, any

fluoroquinolone A quinolone antibiotic is a member of a large group of broad-spectrum bacteriocidals that share a bicyclic core structure related to the substance 4-quinolone. They are used in human and veterinary medicine to treat bacterial infections, as wel ...

, and any of the three second line injectable TB drugs (

amikacin Amikacin is an antibiotic medication used for a number of bacterial infections. This includes joint infections, intra-abdominal infections, meningitis, pneumonia, sepsis, and urinary tract infections. It is also used for the treatment of multi ...

capreomycin Capreomycin is an antibiotic which is given in combination with other antibiotics for the treatment of tuberculosis. Specifically it is a second line treatment used for active drug resistant tuberculosis. It is given by injection into a vein or ...

, and

kanamycin Kanamycin A, often referred to simply as kanamycin, is an antibiotic used to treat severe bacterial infections and tuberculosis. It is not a first line treatment. It is used by mouth, injection into a vein, or injection into a muscle. Kanamycin ...

). TDR-TB has been identified in three countries;

India India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...

Iran Iran, officially the Islamic Republic of Iran, and also called Persia, is a country located in Western Asia. It is bordered by Iraq and Turkey to the west, by Azerbaijan and Armenia to the northwest, by the Caspian Sea and Turkmeni ...

, and

Italy Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical re ...

. The term was first presented in 2006, in which it showed that TB was resistant to many second line drugs and possibly all the medicines used to treat the disease. Lack of testing made it unclear which drugs the TDR-TB were resistant to. The emergence of TDR-TB has been documented in four major publications. However, it is not recognized by the World Health Organization. This is because the term defined as "totally drug resistant", has not been applied to the disease of tuberculosis. Certain strains of TB have not been properly tested to be deemed resistant due to lack of ''

in vitro ''In vitro'' (meaning in glass, or ''in the glass'') studies are performed with microorganisms, cells, or biological molecules outside their normal biological context. Colloquially called "test-tube experiments", these studies in biology an ...

'' testing. TDR-TB has resulted from further mutations within the bacterial genome to confer resistance, beyond those seen in XDR- and MDR-TB. Development of resistance is associated with poor management of cases. As of 2011, drug susceptibility testing is done in less than 5% of TB cases globally Without testing to determine drug resistance profiles, MDR- or XDR-TB patients may develop resistance to additional drugs and can continue to spread the disease to others. TDR-TB is relatively poorly documented, as many countries do not test patient samples against a broad enough range of drugs to diagnose such a comprehensive array of resistance. The

United Nations The United Nations (UN) is an intergovernmental organization whose stated purposes are to maintain international peace and international security, security, develop friendly relations among nations, achieve international cooperation, and be ...

' Special Programme for Research and Training in Tropical Diseases has set up the TDR Tuberculosis Specimen Bank to archive specimens of TDR-TB. There have been a few examples of cases in several countries, including India, Iran, and Italy. Cases of TDR-TB have also been reported in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

. The first case was found in a young man from

Peru , image_flag = Flag of Peru.svg , image_coat = Escudo nacional del Perú.svg , other_symbol = Great Seal of the State , other_symbol_type = Seal (emblem), National seal , national_motto = "Fi ...

named Oswaldo Juarez. Juarez was in the United States for school and to study the English language. About a year later he was voluntarily sent to A.G. Holley State Hospital. They treated him with unconventional drugs that are not usually used for TB in extremely high doses. He stayed in that hospital for over nineteen months, but left cured of TB.

References

External links

MDRIpred
* {{cite journal , vauthors = Singla D, Tewari R, Kumar A, Raghava GP, ((Open Source Drug Discovery Consortium)) , title = Designing of inhibitors against drug tolerant Mycobacterium tuberculosis (H37Rv) , journal = Chemistry Central Journal , volume = 7 , issue = 1 , pages = 49 , date = March 2013 , pmid = 23497593 , pmc = 3639817 , doi = 10.1186/1752-153X-7-49 , doi-access = free Tuberculosis Antibiotic-resistant bacteria

See also

References

External links