Flashcards in Pathogens with Respiratory Transmission Deck (73)
Three primary bacteria discussed in this packet
Staining used for mycobacterium?
Describe the growth of mycobacteria?
Very Slow (18hours)
Growth from one pole
Significance of mycobacteria growth time?
Culturing is too slow for diagnosis
mycobacterial structure associated with virulence?
Serpentine Cord Formation
Describe the mycobacterial cell wall
Made with mycolic acids (very hydrophobic
Waxy part of outer layer
Significance of mycolic acids in mycobacterium? (2)
Prevents lysozyme or complement attack
What is Freund's Adjuvant?
The waxy part of the outer layer of mycobacteriua
What is LAM? Why do we care?
Stimulates cytokine production by mammalian host
TB promotes what other disease?
Symptoms of mycobacterium tuberculosis?
Fatigue, Fever, Night Sweats, Weight Loss, Hemoptysis
Primary presentation of mycobacterium tuberculosis?
Exudative lesion (edema, inflammation)
Three potential responses to exudative lesions?
A productive lesion will cause a _____ to occur. This can cause these two responses.
Encasing or Spreading (via lymph, bronchi, or blood)
Encases granulomas run the risk of
Leads to multiple granulomas, fibrination of lung
Mycobacterium tuberculosis spread in the blood can lead to ...
What is caseum?
Necrotic tissue damaged by inflammatory response and lack of vascularization
Why are caseum especially bad in mycobacterial infection?
The hollowed areas they leave behind may allow encapsulated TB to escape
Prevalence of TB?
2B people in the world infected (30%)
TB at risk populations in the US? (5)
Minorities and Immigrants
Co-Existing Infection (esp. HIV)
Very Young or Old
Travelers in High Risk Areas
How is TB spread?
Person-to-Person via respiratory droplets
What does TB do when in the body?
Attach to alveolar macrophages and invade
Prevent Phagolysosome fusion
Cytotoxicity from cord factor
T or F. TB always presents with primary symptoms of the lungs.
False. Rarely primary extrapulmonary symptoms will occur.
Two sites where long term TB retention may occur.
Granulomas and Bone Marrow.
Two tests used to detect TB?
Mantoux (PPD) Test
QuantiFERON-Gold assay (IGRA)
How does a Mantoux (PPD) Test work?
Intradermal Protein Injection
Sensitivity within 72 hours indicates that Tmem cells were present
How does a QuantiFERON-Gold assay work?
Tests for releave of IFN-g from peripheral lymphocytes when exposed to TB antigen
Best method of diagnosing TB?
Two ineffective means of diagnosing TB?
Culture (too slow)
Acid-fast sputum stain (requires massive inf. to detect)