tuberculosis

Question 1

what is mycobacteria

Answer 1

a few species responsible for human disease like tuberculosis
mon - motile bacillus, very slow growing
aerobic
has a very thick fatty cell wall

Question 2

how is tb spread

Answer 2

airborne
if someone w tb in their lungs coughs
tb is attached to aerosol droplets which can remain suspended in air for many hours especially if theirs poor air circulations
mycobacteria is eliminated by uv radiation and dilution

Question 3

what happens in transmission

Answer 3

activated macrophages —-> epitjeloid cells—-> langhans giant cells
accumulation of macrophages, epitheloid and langhans cells ——> granuloma
central ça seating necrosis

Question 4

how does mycobacteria spread

Answer 4

via lymphatics you draining hilar lymph nodes

Question 5

what can primary infection result in

Answer 5

progressive disease
contained latent
cleared cured

Question 6

how does primary infection progress in a small number of people

Answer 6

to tuberculosis bronchopneumonia
primary focus continues to enlarge - cavitation
enlarged hilar lymph compress bronchi, lobar collapse
enlarged lymph node discharges into bronchus

Question 7

what happens post primary disease

Answer 7

tb bacteria entering dormant stage with low or no replication over prooonged periods of time
balances state of replication and destruction by immune mechanisms

Question 8

what is the clinical presentation of tb

Answer 8

cough
feber
swears
weight loss

Question 9

how is tb diagnosed

Answer 9

spices soft fluffy/modular upper zone, cavitation in 10-30%
lymphadenopathy rare
norma CXR in 13% of définitive pulm

Question 10

when would u consider a CT

Answer 10

normal CXR but clinical suspicion 
military tb 
cavitation and other differential 
lymphadenopathy alternative diagnosis 
targets for BAL

Question 11

how do u diagnose actuve pulmonary tb

Answer 11

mediastinal lymphadenopathy
pleural effusion
miliary

Question 12

how do u make sure u get the bug

Answer 12

sputum - 3 samples 8-24 hrs gap and at least one early morning sample
induces sputum 
bronchoscope w BAL 
endobronchial ultrasound w biopsy 
lumbar puncture in CNS TB 
urine in urogénital TB
aspirate/biopsy from tissue

Question 13

what are the legal requirements for treatment of tb

Answer 13

multiple drug therapy is essential
single agent treatment leads to drug resistant organisms w 14 days
therapy must continue for at least 6 months
tb therapy is a job for committed specialists only
legal requirement to notify all cases
test for HIV, hep b&c

Question 14

what are typical treatments

Answer 14

pyridoxine
steroids
vitamin d

Question 15

how do you screen for latent tb

Answer 15

contacts of pekple with actuve pulmonary or laryngeal tb who are aged