TB, Cocci, Histo, PCP Flashcards
Affects 1/4 of world’s population. Global pandemic with HIV
TB
Causative agent of TB
Mycobacterium tuberculosis
How does TB spread
by airborne droplets from Active TB patients
Is TB chronic or acute
Chronic
After inhaling TB, there are 4 possible outcomes. What are they?
1) clear bacteria
2) Active TB case
3) Latent infection (wall off)
4) Re-activation TB (necrosis breaks through walled off are)
Popcorn: caseous necrosis
TB
Non-necrotising necrosis
Sarcoidosis
How long dose it take for macrophages to wall off TB?
2-8 weeks
Is latent TB infectious?
No
Is Re-activated TB infectious?
Yep
Why do latent TB patients take prophylaxis?
to not develop reactivated TB
What are TB risk factors (CHARMS)?
Children <5, HIV, Alcohol, Radiation (immunetherapy), malnutrition, SUD,
What nationalities have high TB? Triple As
Africans, Asians, Latin Americans
Will a skin test (PPD) for TB be positive for Latent TB?
Yes, Next step is a CXR
SXS of active TB? Classic TB
Fevers, Chills, night sweats, chest pain, anorexia, weakness, fatigue, weight loss.
What does TB look like (another infection)?
Like Pneumonia, post-tussive rales = classic
What does TB look like with a CXR?
Hilar adenopathy at MIDDLE lobe
What does reactivated TB look like with a CXR?
Apical/ Upper lobe infiltrates and cavitations
How do you Diagnose TB
Sputum cytology - NAT Sputum culture = GOLD STND need 3 consecutive in the morning 3 AFB sputum smears = not diagnosable Biopsy = necrotizing caseating granuloma
What do you measure on a TB test?
induration not erythema
what is the 2 step TB test?
Do the first PPD and read it 2-3 days after it is placed. Then repeat the PPD1-3 weeks later if the first one came back negative.
If a patient has a BCG vaccine, will they be positive on the skin test?
yes
What factors causes a patient to have a positive PPD of 5mm?
HIV, Recent contacts, TB on CXR, immune comp
Are the blood draws for TB?
Yes, the IGRA and the T Spot
What are some advantages to an IGRA blood draw for TB?
Done in one visit, results in 24 hours, no booster needed, no reader bias, isnt affected by BCG Vax