TB Flashcards
What is TB?
Mycobacterial infection beginnin the lower airway resulting in caseating necrosis. Can spread to multiple body sites.
Where are most cases of TB found?
Africa and Asia (China and India)
Who is predisposed to TB infection?
HIV Steriod therapy Diabeter Chemotherapy Kidney Disease Malnutrion Homeless Drug addicts Prison inmates
What mycobacteria can cause TB?
Mycobacterium tuberculosis
Mycobacterium bovis
What is the type of sensitivoty associated with TB?
Type four hypersensitivity (delayed granulomas with necrosis)
How is TB spread?
Airborne
Droplet spread
Small number causes infection
What is the difference between primary and secondary TB?
Primary- first infection with Mycobacteria
Secondary- reinfection/reactivation in a person who already has some immunity
Which lymph nodes are drained to in primary TB?
hilar
What is a ghon focus?
Initial focus of the disease in periphery of mid zone of lung
Where does secondary TB tend to localise?
Apices
What are the key symptoms of TB?
Cough Sputum Malaise Weightloss NIGHT SWEATS Haemoptysis Pleurisy Pleural effusion Fever Hoarseness
What investigations would you use to diagnose TB?
ZN stain
PCR
Lowenstein- Jensen culture
What does a positive TB ZN stain look like?
red rods
Why does TB not gram stain?
Waxy coat
Acid alcohol fast bacilli
What is the treatment for TB?
six month antibiotics Rifamcin Isoniazid Pyrazinamide Ethambutamol All for two month, only first two for last two months
