Tuberculosis

Question 1

what type of infection is TB?

Answer 1

mycobacterial infection

Question 2

what is the main pathogen in TB?

Answer 2

M Tuberculosis

Question 3

what body sites can TB occur in?

Answer 3

lung
gut
kidneys
lymph nodes
skin

Question 4

How many people remain well after exposure to TB?

Answer 4

90%

Question 5

Name the symptoms of TB?

Answer 5

persistent productive cough >3wks
haemoptysis
pleuritic pain
hoarseness
upper zone crackles
night sweats fever
weight loss

Question 6

What is the pathology of TB?

Answer 6

granuloma with necrosis

type 4 hypersensitivity reaction

Question 7

why may TB reactivate?

Answer 7

decreased T cell function (age, HIV, Immunosuppressant [steroids, chemo])

-reinfection at high dose or more virulent organism

Question 8

how is TB investigated?

Answer 8

Ziehl Neilsen Stain

CXR

Question 9

How is active TB treated?

Answer 9

4 drugs for 2 months: Rifampicin, Isoniazid, Pyrazinamide, Ethambutol
2 drugs for a further 4 months: Rifampicin, Isoniazid

Question 10

How is Latent TB treated?

Answer 10

2 drugs for 3 months: Rifampicin, Isoniazid

Or 1 drug for 6 months: Isoniazid

Question 11

What is latent TB?

Answer 11

symptom free, no evidence for active TB + evidence of previous TB infection

Question 12

why does HIV increase risk of TB?

Answer 12

Immuno-deficient most at risk group e.g. 25% of deaths occur in HIV +ve

Question 13

what therapy may reactivate TB?

Answer 13

ANTI TNF Therapy