tb Flashcards
what is TB
A contagious and airborne infectious disease caused by bacteria
which bacteria causes TB
Bacteria belonging to mycobacterium tuberculosis complex
is it gram positive or negative and why?
positive
This is because they have a layer of mycolic acid (exterior walls) and peptidoglycan cell wall
what is the life cycle of MTB
1) gets infected via cough by MTB
2) inflammatory response - host macrophages in lungs phagocytise the pathogens
3) bacterial burden is contains din a foamy macrophage
4) formation of granuloma
5) granuloma matures
6) granuloma fuse in the airway and release pathogens
what is latent tb
no symptoms
what is extra pulmonary disease
MTB pathogens enter the blood stream and reach not just the lungs but other organs
who is at risk
-health care worker HIV patients drug users diabetics chronic illness using tobacco
what are the diagnoses for active tb
-sputum microscopy
chest xray
and symptoms
what is the symptoms
-purulent sputum
- cough over 3 weeks
-blood in cough - haemoptysis
fever
weight loss
night sweats
what is the diagnoses for extra pulmonary TB
-ECG
-biopsy
ultrasound
what are some counselling points of rifampicin
-body fluid decolourisation
contradiction with oral contraception
what is the diagnosis for latent tb
-skin test - tuberculin skin test - mantoux test
who can be offered latent tb treatment
-chronic disease
-hiv
younger than 5
-alcohol or drug users
what are the treatment options (first line) for active and what are the doses which needs to be given
isoniazid
ethambutol
pyrazinamide
rifampicin
2 months : all 4
rifampicin and isoniazid - further 4 months
why is all 4 drugs given at the same time
to avoid resistance
