How is TB transmitted?
Must be inhaled
-must be prolonged, repeated, close exposure
-N95 mask prevents transmission
How does the immune system respond to TB?
Macrophages and immune cells form a granuloma in the lungs surrounding the pathogen, stopping it from becoming a disease
-only 5-10% of those with healthy immune responses get the disease
Which 2 groups are at higher risk of not being able to prevent an infection from being active?
Immunocompromised, very young, very old
What is the primary manifestation of TB?
Dry cough that becomes productive with purulent sputum
What are some initial manifestations of TB?
Dry cough
Fatigue, weight loss, low fever, night sweats
What are 2 complications of TB?
Miliary TB: spread to other organs
Pleural TB: reaches pleural space of lungs
What does the TB skin test do?
Tests if the person has EVER had an immune reaction to TB
When is a TB skin test able to be read/assessed?
must be 48-72 hours after application of test
TB skin test
-An induration of ___mm or more is considered positive in high-risk patients?
5 mm
TB skin test
-an induration of __mm or more is considered positive in low-risk patients?
15mm
TB skin test
-an induration of __mm or more is considered positive in medium-risk patients?
10mm
What does a chest xray show for TB?
Chest XRAY shows if there are signs of active TB, but does not diagnose it
How are sputum cultures collected to diagnose TB?
At least 3 consecutive cultures, each collected 8-24 hours apart, with at least 1 early morning specimen
How long does a TB patient need to remain isolated after starting treatment?
2-weeks
Isoniazid
Often the first med for TB
-give with vitamin B to decrease peripheral neuritis
Rifampin
Decreases the effects of birth control and warfarin
Turns urine/sweat/tears orange
Stains contacts- use glasses
Rifabutin
Turns urine/sweat/tears orange
Not safe if pregnant
GI upset: give with food
Ethambutol
GI upset: give with food
Can cause optic neuritis-visual changes
Pyraxinamide
GI upset: give with food
What do all TB meds cause?
Liver toxicity: check for jaundice
How long does TB medication treatment take?
6-12 months on a combo of meds
How is latent TB treated?
Isoniazid for 6-9 months to prevent disease formation
What does the BCG vaccine cause?
A positive TB skin test reaction
