Flashcards in Tuberculosis Deck (17):
What is the clinical presentation of TB?
Slow to resolve chest infection
Does TB affect upper or lower lobes?
Tends to affect upper lobes
Why are mycobacteria bacilli considered to be alcohol and acid fast bacilli?
They retain dye even after exposure to acid and alcohol whereas other bacteria don't.
How does TB appear on a Ziehl-Neelsen (ZN) stain?
The mycobacteria appear as red dots. However, this does not give any indication of sensitivity or species.
How long does PCR testing for TB take?
Why is PCR testing useful?
Gives some indication of species and sensitivity
Why is culture on Lowenstein-Jensen medium still important despite the slow growth time?
Best sensitivity to TB and gives information on antibiotic sensitivity.
What are the four drugs used to treat TB?
Why must an eye test be given before administration of ethambutol?
May cause optic neuritis and blindness. Patients must report any difficulties or changes in vision after starting this drug. LFTs must also be checked.
Which drug causes yellow body fluids?
Which two drugs are only taken for two months?
What is the only form of TB that is infectious?
How is TB spread?
Airborne droplets containing TB
How is the spread of TB infection halted in the lungs?
Granuloma formation occurs through cell-mediated immunity by activated T-lymphocytes and macrophages
This gives rise to the latent disease - the disease may never become active
Why does latent TB become active?
Will not become activated unless there is a deficiency in cell-mediated immunity
Active disease presents when a host’s immune response cannot contain MTB replication
What is the definition of pulmonary TB?
Pulmonary TB is defined as active TB that is affecting any of the following:
Mediastinal lymph nodes