TB Flashcards
What statistic is significant about TB?
- Second leading cause of death from an infectious disease
How does TB proliferate the formation of granuloma?
- Activation of macrophages
- Epitheliod cells
- Langhans giant cells form
- Accumulation = granuloma
What can the granuloma cause?
- Central caseating necrosis
What can occur to the central caseating necrosis if left untreated?
- Can calcify
What can TB do in susceptible hosts?
- Tissue destruction
- Proliferation of other organisms
- Progressive disease
Where does lymphatic spread of TB occur?
- Lungs
- Bones
- Genitourinary system
What are the initial symptoms of TB?
Usually none
- Fever
- Malaise
- Erythema nodosum
- Chest signs (rare)
What are the symptoms following primary pulmonary TB?
Usually none but
- Fever
- Malaise
- Cough
- Sputum
- Haemoptysis
- Pleuritic pain
- Dyspnoea
- Weight loss
What are the signs are primary pulmonary TB?
- Erythema nodusum
- Crackles
- Bronchial breathing
- CAN HAVE FINGER CLUBBING BUT VERY RARE
What are the risk factors of TB?
- Malnutrition
- Dependent age
- Diabetes
- Immunosuppression
- Previous TB
- Alcohol
- IVDA
- Poor social class
- Immigrant from high incidence areas
What are the two common organisms that cause TB?
- Mycobacterium TB
- Mycobacterium bovis
How is mycobacterium TB diagnosed?
- Needs to grow first
- Can’t be identified until then
What does myco mean?
- Fungus
How do mycobacterium TB and bovis spread between hosts?
- Droplets
- Can remain airborne for a long time
What is performed first in screening for TB?
- Heaf test
- Mantoux test
What is the mantoux test?
- Injection of tuberculoprotein
- Results in lymphocytic/macrophage accumulation in administered site
- If no such recruitment occurs test is negative
What other diagnostic test is there for TB?
3 sputum specimens on successive days
- Sputum smear (ziehl nielsen stain)
- Sputum test
- Sputum PCR
What will be the findings on a CXR of a TB sufferer?
- Patchy shadowing on apices/upper zones
- Apex of lower zones can be affected
- Often bilateral
- Cavitation if advanced TB
- Calcification possible if chronic/healed
If sputum tests are negative what is the next step?
- CT scan of thorax
- Bronchoscopy
- Pleural aspiration/biopsy
How would a bronchoscopy be performed?
- Broncheoalveolar samples + biopsy
- Z-N stain
- Culture
- PCR
- Histology
What others tests should be done with TB?
- HIV tests
What should be done to people in close contact to the patient?
- Should all be screened as 1 in 6 will develop disease
What type of treatment should be followed for TB?
- Multiple drug treatment along with santorium regime
What happens if you use single drug treatment for TB?
- Rapid resistance
