1. Compare the number of organisms present in cavitary pulmonary TB and TB infection without the disease. Explain how this affects treatment.
    • - Cavitary pulmonary TB: 10^7 - 10^8 organisms
    • - TB infection w/o disease: <10^5

    Because mutations occur in ~1/10^6 to 1/10^8 organisms, multiple drugs must be used to treat cavitary pulmonary TB in order to prevent emergence of resistant strains. TB infection w/o the disease, however, has few enough organisms that mutation is unlikely and can, therefore, be treated with a single drug.
  2. When is an induration > or = to 5mm indicative of TB infection?
    • For persons with:
    • - HIV
    • - immunosuppressive therapy
    • - close contact with infectious cases
    • - fibrotic lesions on CXR
  3. When is an induration > or = to 10mm indicative of TB infection?
    • When the person is:
    • - an immigrant w/i the last 5 years
    • - an IV drug user
    • - a hospital employee
  4. What size induration is indicative of TB infection in persons with no defined risk?
    PPD induration > or = to 15mm.
  5. What is the preferred treatment for latent TB?
    INH (isoniazid) daily for 9 months.
  6. What factors increase a person's risk of developing TB?
    • - smoking tobacco
    • - vitamin D deficiency
  7. What factors should be considered when taking INH?
    Food decreases absorption and INH should be given on an empty stomach.
  8. Toxicities of INH.
    • - Hepatitis: incidence increases with age; liver enzymes should be monitored in persons >35 y/o.
    • - Peripheral neuropathy: caused by interferance with pyridoxine (B6) metabolism; prevent/treat with pyridoxine daily
    • - Diarrhea: secondary to sorbitol in liquid form of INH
  9. Drug interactions of INH.
    Phenytoin: will increase concentration of both drugs in system
  10. Rifampin, Rifabutin, Rifapentine
    Used to treat TB (not usually first line drug).
  11. Administration considerations for Rifampin, Rifabutin, Rifapentine.
    • - Turns body fluids orange; excreted in urine, tears, and sweat.
    • - Give on empty stomach.
    • - Rifampin/Rifabutin are 1x/day; Rifapentine is 1x/week
  12. Toxicities of Rifampin, Rifabutin, and Rifapentine.
    • - Common: GI (nausea, vomittine)
    • - Rare: hepatitis
    • - Orange colored body fluids
  13. Drug interactions with Rifampin, Rifabutin, Rifapentine.
    • Rifampin, Rifabutin, and Rifapentine are potent inducers of hepatic enzymes and therefore reduce blood levels of:
    • - methodone (leading to withdrawl)
    • - warfarin (leading to decreased INR)
    • - oral contraceptives (leading to decreased effectiveness)
  14. Pyrazinamide
    TB treatment
  15. Toxicities of Pyrazinamide.
    • Hepatitis (monitor liver enzymes)
    • GI (nausea, vomitting)
    • Hyperuricemia (decreases uric acid secretion)
  16. Ethambutol
    TB treatment
  17. Toxicities of Ethambutol.
    - Optic neuritis (blurred vision, red/green blindness, restricted visual fields); dose related; do regular eye exams
  18. Quinolone antibiotics
    • TB treatment.
    • Includes: levoflozacin and moxifloxacin
  19. Combination TB drugs.
    • Rifamate: INH and Rifampin
    • Rifater: INH, Rifampin, and Pyrazinamide
Card Set
Pharm Exam 4, part 1