What are the mechanisms of drug resistance in tuberculosis?
Drug resistance in TB occurs through two main mechanisms: (i) primary or transmitted drug resistance, occurs when resistant strains are transmitted to a new host, and (ii) secondary or acquired drug resistance, which occurs through the acquisition of drug resistance mutations to one or more drugs.
How does Mycobacterium tuberculosis become drug resistant?
Drug resistance in TB remains a man-made phenomenon. It emerges as a result of spontaneous gene mutations in M. tuberculosis that render the bacteria resistant to the most commonly used anti-TB drugs. Among the reasons for this, the non-compliance with the treatment regimens is signaled as the first cause.
Why Mycobacterium tuberculosis is highly resistant to many drugs?
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.
What drugs is Mycobacterium tuberculosis resistant to?
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).
Which of the following drug is effective against Mycobacterium tuberculosis and Mycobacterium leprae?
Nitazoxanide (NTZ) is an anti-parasitic drug that also has activity against bacteria, including Mycobacterium tuberculosis. Our data using both radiorespirometry and live-dead staining in vitro demonstrate that NTZ similarly has bactericidal against M. leprae.
Which medication directly inhibits mycolic acid synthesis in the Mycobacterium quizlet?
Isoniazid is an antimetabolite that interferes with mycolic acid synthesis in mycobacteria.
What is the mechanism of action of PAS?
It is a highly-specific bacteriostatic agent active against M. tuberculosis. Its mechanism of action is thought to be similar to the sulphonamides, a competitive antagonism with PABA.
Which of the following drugs is effective against intracellular organism of tuberculosis?
tb infection (isoniazid, rifampicin, pyrazinamide and ethambutol) are all active against actively-replicating bacteria,21 however effectiveness of this drug regimen against non/slowly-replicating bacilli is reduced or eliminated.
Which anti tuberculosis medication inhibits the DNA and RNA synthesis in the mycobacterium?
Rifampin (Rifadin) Rifampin is used in combination with at least 1 other antituberculous drug for the treatment of active TB. It inhibits DNA-dependent RNA polymerase activity in bacterial cells but not in mammalian cells.
Which medication directly inhibits mycolic acid synthesis?
The drugs shown to inhibit mycolic acid biosynthesis are isoniazid, ethionamide, isoxyl, thiolactomycin, and triclosan. In addition, pyrazinamide was shown to inhibit fatty acid synthase type I which, in turn, provides precursors for fatty acid elongation to long-chain mycolic acids by fatty acid synthase II.
What is mechanism of action of PAS para aminosalicylic acid )? *?
Mechanism of Action: Aminosalicylic acid is bacteriostatic against Mycobacterium tuberculosis. It inhibits the onset of bacterial resistance to streptomycin and isoniazid.