Tuberculosis Flashcards
(27 cards)
Has Tb been around for a long time? Why?
Yes- for 5,000 years! It’s adapted to infect humans
Tb was on the way to eradication until what disease became more prevalent?
AIDS
What kind of Tb is a public health nightmare?
Multidrug resistant and extreme drug resistant Tb
Do mycobacterium gram stain well?
No
What kind of stain can you visualize them with?
Acid-fast
Are mycobacterium slow growing or fast growing?
Slow growing
What are the steps of the Acid-Fast stain?
1) Cover with carbofuchsin and steam
2) Decolorize with acid-alcohol
3) Rinse with water
4) Counterstain with methylene blue
5) Rinse and examine
How do you know if a bacterium is acid-fast?
They hold the carbofuschin during the rinse
How is Tb transmitted into the body?
Inhalation
Where does Tb spread and by what route?
Lymph nodes, kkidneys, bones, CNS all by blood
GI tract by swallowing infected sputum
How does an immunocompetent individual react when infected with Tb?
They raise a strong CMI response and can hold infection latent for decades
Why does Tb reactivate?
Immunosenescene or immunosuppression
Do macrophages spread or clear Tb?
Both!
Naïve macrophages spread the intracellular infection
Activated macrophages clear it
What is the role of CD8 cells?
To kill infected macrophages and establish caseating granulomas in which the infection is contained
What is the role of TNF-alpha?
Important for containment of infection
How does classic pulmonary Tb present?
Cough, weight loss, fever, night sweats, hemoptysis, chest pain
What tests should you run if you suspect someone has Tb?
Check sputum and get Chest Xray
What are some extrapulmonary manifestations and tests to diagnose in those regions?
Scrofula- fine needle aspirate GU- IV urography, urine culture CNS- MRI, spinal tap Skeletal- MRI, joint fluid culture GI- xray, abdominal CT Miliary- chest xray, with bright spotlight, lateral xray, chest CT
Is pediatric Tb recently acquired or not?
Recently acquired (no time for latency)- look for source
What should you watch for with pediatric TB?
Miliary Tb and meningitis
Where do you culture from with pediatric Tb?
Gastric Lavage
First step is to determine exposure- how do you do this?
With TST and/or IGRA
As soon as cultures grow, what should you do?
Antibiotic resistance testing
Treatment plan for Tb
Directly observed therapy with 4 plus drug course featuring isoniazid and isolate patient for first two weeks
