TB TCD Flashcards
TB is caused by…
Mycobacterium tuberculosis
complex
Is TB a notifiable disease?
Yes - refer to Health protection Agency HPA
Vaccine for TB
BCG vaccine (Live M. Bovis)
How much of the worlds population is infected with TB?
1/3
Where in the UK is TB highest?
Urban areas
Staining characteristics of mycobacteria
Acid And Alcohol Fast (AAFB)
How is TB spread?
Sputum smear-positive droplet infection
Is the primary infection normally symptomatic?
It is not symptomatic in 90%
Pathology timeline of TB
Primary infection - small lung lesion and regional lymph nodes. Post-primary disease - much greater immune response and usually symptomatic
Where do the mycobacteria hide?
In the macrophages. it’s when they become re-activated that the disease gets clinically bad
Is TB just a pulmonary disease?
No, it’s only Pulmonary in 54% of cases e.g lymph node tuberculosis, bone TB. Symptoms are site specific?
Is TB a common differential?
Yes
TB investigations
CXR ESR CRP HIV LFT Microbiology samples for any infected site
Post primary disease Chest findings
Very varied.
Classic stain used for TB
Ziehl-Neelsen for Acid fast bacilli, culture and drug sensitivities take 2-6 weeks
