First Line Drugs for Tuberculosis MCQs

Teduglutide It is a recombinant analog of human glucagon like peptide 2(GLP 2)(Option B) It is used for the treatment of adults with short bowel syndrome(Option A) It works by promoting mucosal growth and possibly restoring gastric emptying and secretion and is a gut hormone.(Option D) It is given by subcutaneous route It is long acting drug because it is resistant to degradation by DPP-4

Pyrazinamide is an important front-line drug used in conjunction with isoniazid and rifampin in short-course (i.e., 6-month) regimens as a “sterilizing” agent active against residual intracellularorganisms that may cause relapse. Tubercle bacilli develop resistance to pyrazinamide fairly readily, but there is no cross-resistance with isoniazid or other antimycobacterial drugs. REFERENCE: KD TRIPATHI Essential of Medical Pharmacology 7 th Edition Page no. 765-779

This patient with latent tuberculosis infection (positive tuberculin skin test, no symptoms, unremarkable chest x-ray) was started on isoniazid (INH) therapy and now has fever, anorexia, and nausea. INH is directly hepatotoxic. In 10% - 20% of patients, it causes acute, mild hepatic dysfunction, characterized by transient increases in serum aminotransferases (AST/SGOT, ALT/SGPT). This adverse effect usually occurs during the first 4-6 months of treatment, and, in most cases, liver function tests return to baseline with continued INH therapy. In rare instances ( Reference: Harrison's principles of internal medicine - 20 th addition Page no. 1273-1274

M kansai is susceptible to rifampin and ethambutol, partially susceptible to isoniazid, and completely resistant to pyrazinamide. A three-drug combination of isoniazid, rifampin, and ethambutol is the conventional treatment for M kansai infection. Reference: Basic & Clinical Pharmacology, 14th Edition By Bertram G. Katzung Page no. 849-850

Bactericidal drugs: A substance that directly kills bacteria. Bacteriostatic drugs: A substance that stops bacteria from reproducing (does not directly kill bacteria). Rifampin, Isoniazid and Streptomycin are bactericidal drugs. Where as ethambutol and Pyrazinamide are bacteriostatic drugs. REFERENCE: Basic & Clinical Pharmacology, 14th Edition By Bertram G. Katzung Page no. 842-849

Bactericidal drugs: A substance that directly kills bacteria. Bacteriostatic drugs: A substance that stops bacteria from reproducing (does not directly kill bacteria). Rifampin, Isoniazid and Streptomycin are bactericidal drugs. Where as ethambutol and Pyrazinamide are bacteriostatic drugs. The following antituberculosis drugs are contraindicated in pregnant women: Streptomycin Kanamycin Amikacin Capreomycin Fluoroquinolones Reference: Basic & Clinical Pharmacology, 14th Edition By Bertram G. Katzung Page no. 842-849

Isoniazid has maximum CSF penetration. And Streptomycin has minimum CSF penetration. REFERENCE: KD TRIPATHI Essential of Medical Pharmacology 7 th Edition Page no. 765-779

Isoniazid is an antimicrobial agent that is active only against mycobacteria. Its specificity is derived from its inhibition of mycolic acid synthesis. Mycolic acids form long branched-chain fatty acids in the outer portion of the mycobacterial peptidoglycan cell wall; they are essential for proper cell wall structure and virulence factor synthesis (eg, sulfatides, wax D, cord factor). If mycobacteria are unable to synthesize mycolic acids, they cannot create proper cell walls or divide to form new cells. Mycolic acids in the cell wall cause mycobacteria to be acid-fast as they retain the carbolfuchsin dye and resist decoloration by an acid-alcohol decolorizing agent. REFERENCE: KD TRIPATHI Essential of Medical Pharmacology 7 th Edition Page no. 765-779