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
When there is a plural effusion sample what are the types you are looking for
Eosinophilic - not TB
Lymphocytic - TB
HIstological feature of TB
Granuloma
PCR use in TB
Species identification and resistance identification
Drug for acid TB
Pyrazinamide
Drugs for rapidly dividing TB
Isoniazid, rifampicin and streptomycin
Drugs for Dormant TB
Rifampicin and strptomycin
Four key drugs for TB
Isoniazid
Rifampicin
Pyrazinamide
Ethambutol
Which TB drugs require LFTs?
Isoniazid, rifampicin and pyrazinamide
Tuberculin skin testing
Mantoux
