Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
24 Cards in this Set
- Front
- Back
3 species of mycobacteria of importance in humans:
|
M. tuberculosis- TB
M. leprae- leprosy M. intracellulare- disseminated disease in immune suppressed |
|
Where do mycobateria replicate in a lung?
|
alveolar macrophages
|
|
Immune response to mycbacteria in the lungs
|
granulomas
Granulomas become calcified nodules (Gohn complex) |
|
Bacteria within granulomas are unable to replicate but remain viable for how long?
|
years-decades
|
|
Mycobacteria are Acid-fast, aerobic ____
|
rods
|
|
______ tuberculosis (TB) is the widespread dissemination of Mycobacterium tuberculosis from hematogenous spread
|
Miliary
(1-3% of all TB cases) |
|
6% of Primary tuberculosis is "_______" TB
|
clinical
|
|
90% of primary TB is "_____" TB.
|
latent
|
|
What causes Secondary (reactivated) tuberculosis?
|
Immune suppression allows latent TB to reactivate
Granulomas break down releasing organisms Clinical TB results |
|
Manifestations of Reactivated Pulmonary TB
|
Insidious onset of fever, night sweats, weight loss, anorexia, malaise, weakness
Cough often productive of blood-streaked sputum Apical and posterior segments of upper lobes most often affected May see cavitary lesions on CXR |
|
extrapulmonary tuberculosis that affects the spine
|
Pott disease
|
|
Infected macrophages can take TB hematogenously throughout body if _____ law is broken
|
Jason's
|
|
TB:
_____ stain of sputum |
Acid fast
|
|
TB:
Culture in broth takes up to ___ days |
14
|
|
agar used to culture TB (takes a month)
|
Lowenstein-Jensen agar
|
|
PPD test:
Within 48 hours, a positive lesion is erythematous and _____ |
indurated
15mm induration is positive in persons with latent TB |
|
10mm post-PPD induration is positive for:
|
Recent arrivals from high-prevalence countries ****
Injection drug users Residents and employees of high-risk congregate settings Mycobacteriology laboratory personnel Persons with clinical conditions that place them at high risk Children <4 years of age, or children and adolescents exposed to adults in high-risk categories |
|
5mm post-PPD induration is positive for:
|
Immunosuppressed patients (HIV/AIDS, cancer, etc.)****
Persons with fibrotic changes on chest radiograph consistent with old healed TB |
|
First line treatment of TB
|
Requires 4 drug cocktail
First line drugs Isoniazid (INH) Rifampin Ethambutol Pyrazinamide |
|
Second line drugs for TB
|
Streptomycin
Para-aminosalicylic acid Cycloserine Ethionamide Amikacin Levofloxacin Capreomycin |
|
Treatment of active TB with 4 drug cocktail lasts for 2 months. Then the pt has CXR and AFB smear. If CXR and smear are NEGATIVE, continue isonaiazid and rifampin for how long?
|
4 more months
(7 more months if AIDS pt) |
|
Multi-drug resistant TB (MDR-TB)
Resistant to what? |
INH and Rif
Can still be treated by substituting second-line drugs |
|
Extensively drug-resistant TB (XDR-TB)
|
INH, Rif, any fluoroquinolone
and at least one of three injectable second-line drugs (capreomycin, kanamycin, and amikacin) |
|
For latent tuberculosis, the standard treatment is six to nine months of
|
isoniazid alone.
|