Bacterial Diseases of Lower Respiratory Tract- TB Flashcards
bacterial disease of lower respiratory tract that is caused by mycobacterium tuberculosis; spreads from human to human transmission
tuberculosis
Pathogenesis of TB
- Alveoli macrophages ingest mycobacteria. Infection present but no symptoms; creates environment where they can multiply
- Bacteria survive & multiply, more macs recruited to site; tubercle forms & macs cannot destroy bacteria. They release enzymes & cytokines that cause lung damaging inflammation
- Few weeks later, symptoms appear, tubercle enlarges via liquefaction & TB cavity is formed where it multiples outside of walled off macrophages
- Liquefaction continues until tubercle ruptures to bronchioles>lungs>circulatory & lymphatic tissues
Treatment of Tuberculosis
prolonged treatment w/ multiple antibiotics for up to 6 months
What does a rupturing tubercle cause?
lung defect aka tuberculous cavity that spreads bacteria to other parts of lung
Lung defect aka tuberculous cavity can exist for how long?
months to years as it enlarges and sheds bacteria into bronchii
finding on chest X ray that signifies tuberculosis
Ghons Complex
Tuberculosis spread from human to human via
coughing/spitting/ droplets in air
Positive Tuberculin PPD Test suggests
current or previous infection of TB
asymptomatic Mycobacterium tuberculosis infection in which the bacterium is held in check by the immune system.
latent tuberculosis infection (LTBI)