Mycobacterium tuberculosis is intrinsically resistant to many antibiotics, limiting the number of compounds available for treatment. This intrinsic resistance is due to a number of mechanisms including a thick, waxy, hydrophobic cell envelope and the presence of drug degrading and modifying enzymes.
Full Answer
What helps tuberculosis (TB) bacteria resist antibiotics?
Treatment of tuberculosis (TB) has been a therapeutic challenge because of not only the naturally high resistance level of Mycobacterium tuberculosis to antibiotics but also the newly acquired mutations that confer further resistance. Currently standardized regimens require patients to daily ingest up to four drugs under direct observation of a healthcare worker for a period of 6–9 …
What are the different types of drug resistant tuberculosis?
Antibiotic-resistant Mycobacterium tuberculosis strains are threatening progress in containing the global tuberculosis epidemic. Mycobacterium tuberculosis is intrinsically resistant to many antibiotics, limiting the number of compounds available for treatment. This intrinsic resistance is due to a number of mechanisms including a thick, waxy, hydrophobic cell envelope and the …
How is drug resistance acquired in tuberculosis (TB)?
Jun 12, 2009 · KatG (catalase-peroxidase) in Mycobacterium tuberculosis is responsible for activation of isoniazid (INH), a pro-drug used to treat tuberculosis infections. Resistance to INH is a global health problem most often associated with mutations in the katG gene. The origin of INH resistance caused by the KatG[S315G] mutant enzyme is examined here.
How do multidrug resistant tuberculosis strains evolve to regain fitness?
Extensively drug-resistant TB (XDR TB) is a rare type of MDR TB that is resistant to isoniazid and rifampin, plus any fluoroquinolone and at least one of three injectable second-line drugs (i.e., amikacin, kanamycin, or capreomycin). Treating and curing drug-resistant TB is complicated. Inappropriate management can have life-threatening results.
Is Mycobacterium tuberculosis resistant to antibiotics?
Mycobacterium tuberculosis is intrinsically resistant to many antibiotics, limiting the number of compounds available for treatment. This intrinsic resistance is due to a number of mechanisms including a thick, waxy, hydrophobic cell envelope and the presence of drug degrading and modifying enzymes. Resistance to the drugs which are active ...
Is M. tuberculosis genetically diverse?
Although the genetic diversity of M. tuberculosis is low compared to other pathogenic bacteria, the strain genetic background has been demonstrated to influence multiple aspects in the evolution of drug resistance. The rate of resistance evolution and the fitness costs of drug resistance mutations may vary as a function of the genetic background.
How do mutations affect drug resistance?
These chromosomal mutations may confer drug resistance via modification or overexpression of the drug target, as well as by prevention of prodrug activation. Drug resistance mutations may have pleiotropic effects leading to a reduction in the bacterium's fitness, quantifiable e.g. by a reduction in the in vitro growth rate.
What is a drug resistant TB?
Drug-resistant tuberculosis (TB) is TB disease caused by M. tuberculosis organisms that are resistant to at least one first-line anti-TB drug. Multidrug-resistant TB (MDR TB) is resistant to more than one anti-TB drug and at least isoniazid (INH) and rifampin (RIF). Treating and curing drug-resistant TB is complicated.
How long does it take to test for drug resistance?
Drug resistance is proven by drug-susceptibility testing. However, since this testing can take weeks , treatment should be started with an empirical treatment regimen based on expert advice as soon as drug-resistant TB disease is suspected. When the testing results are known, the treatment regimen should be adjusted according to the results.
What is DOT in TB?
Patients should be monitored closely throughout treatment. Directly observed therapy (DOT) always should be used in the treatment of drug-resistant TB to ensure adherence.
Can fluoroquinolones be used for children?
Long-term use of fluoroquinolones in children has not been approved. However, most experts agree that these drugs should be considered for children with MDR TB. Consultation with a specialist in pediatric TB treatment is recommended. Pregnant Women.
What are some examples of drug resistant TB?
Causes of Drug Resistant TB. Drug-resistant TB can occur when the drugs used to treat TB are misused or mismanaged. Examples of misuse or mismanagement include. People do not complete a full course of TB treatment. Health care providers prescribe the wrong treatment (the wrong dose or length of time)
Can TB be treated?
In most cases, TB is treatable and curable; however, people with TB can die if they do not get proper treatment. Sometimes drug-resistant TB occurs when bacteria become resistant to the drugs used to treat TB. This means that the drug can no longer kill the TB bacteria.
Can TB be curable?
TB usually affects the lungs, but it can also affect other parts of the body, such as the brain, the kidneys, or the spine. In most cases, TB is treatable and curable; however, people with TB can die if they do not get proper treatment. Sometimes drug-resistant TB occurs when bacteria become resistant to the drugs used to treat TB.
How is TB spread?
TB is spread through the air from one person to another. The TB bacteria are put into the air when a person with TB disease of the lungs or throat coughs, sneezes, speaks, or sings. People nearby may breathe in these bacteria and become infected. Causes of Drug Resistant TB.
Is TB resistant to fluoroquinolone?
TB experts should be consulted in the treatment of MDR TB. Extensively drug-resistant TB (XDR TB) is a rare type of MDR TB that is resistant to isoniazid and rifampin, plus any fluoroquinolone and at least one of three injectable second-line drugs (i.e., amikacin, kanamycin, or capreomycin).
What is XDR TB?
Extensively Drug-resistant TB (XDR TB) Extensively drug-resistant TB (XDR TB) is a rare type of MDR TB that is resistant to isoniazid and rifampin, plus any fluoroquinolone and at least one of three injectable second-line drugs (i.e., amikacin, kanamycin, or capreomycin). Because XDR TB is resistant to the most potent TB drugs, ...
Is MDR TB rare?
Economic Toll of Drug-Resistant TB. While MDR TB and XDR TB are relatively rare in the U.S., their treatment comes at a terrible price – it is very expensive, takes a long time to complete, disrupts lives, and has potentially life-threatening side effects.
What is the name of the bacteria that causes TB?
Mycobacterium tuberculosis, the bacteria that cause TB. NIAID. Researchers designed and tested a class of new antibiotics to treat tuberculosis. The work represents an initial step in developing therapies to combat drug-resistant forms of the disease.
How long does TB last?
Multidrug-resistant (MDR) TB currently requires treatment for up to 2 years with several antibiotics that may have serious side effects. Extensively drug-resistant (XDR) TB has been reported in 92 countries, with some strains resistant to all available drugs.
What is the cause of TB?
Mycobacterium tuberculosis, the bacteria that cause TB. NIAID. Researchers designed and tested a class of new antibiotics to treat tuberculosis. The work represents an initial step in developing therapies to combat drug-resistant forms of the disease. TB is a contagious disease caused by infection with Mycobacterium tuberculosis (Mtb) bacteria.
Is TB a contagious disease?
The work represents an initial step in developing therapies to combat drug-resistant forms of the disease. TB is a contagious disease caused by infection with Mycobacterium tuberculosis (Mtb) bacteria. It’s spread through the air and usually affects the lungs.
How does TB spread?
TB is a contagious disease caused by infection with Mycobacterium tuberculosis (Mtb) bacteria. It’s spread through the air and usually affects the lungs. It's a leading cause of disability worldwide and results in 1.3 million deaths per year. TB is treated with antibiotic drugs.
How does spectinomycin work?
Spectinomycin works by binding to bacteria’s ribosomes, which are a crucial part of the cell’s protein-making machinery. The researchers analyzed the drug’s structure and made various chemical modifications to create a new class of agents known as spectinamides.