Ch 27 Flashcards
tuberculosis causative agent? aka?
a. Caused by acid-fast bacillus Mycobacterium tuberculosis
b. aka tubercle bacillus
tuberculosis how many affected?
c. One of world’s major health problems, killing more persons than any other infectious disease, including AIDS
d. Affects more than 1.5 million people with 8 million new cases each year
who is more susceptible to TB?
f. alcoholics, AIDS, and debilitative conditions
antitubercular drugs
a. Isonizaid (INH): first drug demonstrating effectiveness against the tubercle bacillus
b. prophylaxis
e. Different combination of drugs can be used as multidrug therapy is more effective
f. If multidrug resistance develops other antibacterial agents can be used
what is recommended for individuals who have been in close contact with persons with TB, or who test positive for HIV, or a positive TB skin test?
prophylaxis
c. If a person is diagnosed with TB, family members may be given prophylactic doses of isoniazid for 6 months to 1 year
when are patients considered noninfectious for TB?
Considered noninfectious when patient meets ALL (3) criteria
i. Three consecutive negative AFB sputum smears collected in 8- to 24-hour intervals (one should be an early morning specimen)
ii. Compliant with treatment regimen for two weeks or longer
iii. Symptoms have improved clinically (are coughing less and no fever)
isoniazid (INH) type of drug? mechanism of action?
antitubercular drug - inhibits bacterial cell wall synth.
antifungal drugs
nystatin
azole group
polyenes
Amphotericin B - risk, PT, PD, Adv, NI
(polyene) (amphoterrible) (IV only)
1. Monitored closely: risk of toxicity - nephrotox, electrolytes(hypokalemia/hypomagenesemia)
2. Effective against numerous fungal diseases (mostly for severe fungus)
3. binds to fungal cell membrane, forming open channels increasing cell permeability: leakage of intracellular components
5. Must watch urine output closely and renal function closely, an electrolytes
why are pregnant women at risk with TB?
can cross placenta.
nystatin route, PD, effect, PT, NI, pt ed
PK: PO or topical: suspension, cream, ointment, vaginal tablets. (Most common = oral suspension)
PD: Increases permeability of the fungal cell membrane: fungal cell becomes unstable
b. Fungistatic and fungicidal
PT: Candida
NI: Assess mucous membrane, oral cavity prior to administration
PT ED: Patient must swish the medication in their mouth > spit it out
azole group PD, forms it is used in
i. Inhibit cytochrome P450 in fungal cells, interfering with formation of ergosterol, a major sterol in fungal cell membrane > increased cell permeability and leakage
ii. Used in topical preparations, vaginal tablet, cream, ointment, and solution
fluconazole(Diflucan) PD, PT, prec, SE, D/F/L, NI, pt ed
PD: inc permeability of fungal cell membrane
PT: Candida, cryptococcal meningitis
Prec: pregnant
no adv known
SE: vaginal rash/burning, anorexia, n/v/d, stomach cramps, rash, headache
DFL: ^PT w/warfarin, ^hypoglycemia w/sulfonylureas, ^seizure meds, dec level with cimedtidine and rifampin
NI: assess renal/hepatic prior (ci), obtain culture first, monitor urine.
Pt ed: no alc/driving
viruses
more difficult to eradicate than most bacteria.
obligate intracellular organisms: must reside in living host cell to survive/reproduce
viral infections
influenza hepatitis B herpesviruses a. HSV-1: herpes simplex virus b. HSV-2: herpes simplex virus c. HSV-3: varicella zoster virus d. HSV-4: Epstein-barr e. HHV-5: Cytomegalovirus