TB Flashcards
What bacterium causes TB
Mycobacterium tuberculosis
Full Latin name for TB
Mycobacterium tuberculosis
What group in the US is more likely to have TB
Foreign-born individuals
What are the six risk factors of TB
Malnutrition
Immunosuppressed
Overcrowded living conditions
Institutional living
HIV
Alcohol abuse
How do most people present with TB
Asymptomatic
Maybe slight fever
Many don’t seek treatment
Describe mycobacterium tuberculosis
Long rod shape
Slow growing
Waxy capsule
Resistant to gram stain
Need fast acid
What are non aerosol ways to contract TB
Direct inoculation through skin during post-mortem
Other than by mouth how else can you inhale TB aerosols
Improperly handling infected fluids (urine, feces)
What are classic presentations of TB (vitals and what you see)
Chronic (wracking) cough
Hemolysis
Wasted appearance
Tachycardia
Tachypnea
Classic symptoms of TB
Fever/chills
Soaking night sweats
Fatigue
Loss of appetite
What about a patients history can indicate TB
Recent weight loss
What might be heard during auscultation during TB
Crackles
Pleural friction rub
What is heard during percussion of a TB patient
Dullness over apices
What is seen on a CXR of a TB patient
Lymphadenopathy (first)
Primary TB
Cavitation
Post primary TB
Where in a CXR is pathology of TB focused
Middle and Apices (oxygen rich)
Who is a the highest risk of death associated with TB
The old and very young
Define Tuberculosis
Contagious, chronic infection from mycobacterium tuberculosis
By how much did the incidence of TB increase from 2020-2023
4.6%
Risk factors for TB (6)
Malnutrition
Institutional living
Living in crowded conditions
Immunosuppression
HIV
Alcohol abuse
Who in the US is more likely to have TB
Foreign-born individuals
Describe the bacteria that causes TB
Long rod
Slow growing
Waxy capsule
Resistant to gram stain
Acid fast!!
How is TB spread
Aerosolize droplets
Not touching objects (fomites)
Other than aerosolized droplets how can you contract TB
Direct inoculation through skin during post-mortem
Other than by mouth how can you come in contact with TB aerosols
Improperly handling infected fluids and inhaling them (urine, feces)
How do patients with TB usually present
Usually asymptomatic
Maybe slight fever
(Don’t get assessed)
Classic TB presentation (vitals and look)
Chronic (wracking) cough
Hemolysis
Wasted appearance
Tachycardia
Tachypneic
Classic symptoms of TB
Fevers, chills
Soaking night sweats
Fatigue
Loss of appetite
What history of presentation might a TB patient have
Recent weight loss
What will you hear during auscultation of a TB patient
Crackles, pleural friction rub
What is heard during percussion of a TB patient
Dull in apices
What are the three groups of TB
Primary TB
Post primary TB
Disseminated TB
What is the process of development of primary TB
Follows initial exposure
What inhaled bacilli implant in alveoli
Over 3-4 weeks bacteria multiply
How do the lungs react to primary TB
Inflammation
(Similar to acute PNA)
What is the process of development of primary TB
Neutrophils and MACs attempt to engulf bacilli but can’t kill them
Pulmonary cap dilate and interstitium fills w/ fluid
Alveolar edema
Patient has a positive ppd test
What does the lungs do what they can’t kill TB
Tissue will create a granuloma or tubercle to encase it
How does the TB tubercle core look
Cheese-like necrosis mixed with TB bacilli surrounded by WBCs
What is the initial lesion from TB called on a CXR
Ghon nodule or Ghon focus
What TB classification does reactivation TB fall under
Post primary TB
How long does it take for a tubercle in TB to form
2-10 weeks
What are the two ways TB bacilli can be controlled
The immune system
Antibiotics
What replaces the tubercles
Tissue fibrosis and calcification of the lung parenchyma
Once calcified the Ghon complex is termed…
The Ranke complex
What is the remaining scared and retracted TB lung tissue at risk of
Distorting the bronchi to the point of Bronchiectasis
What causes reactivation of TB
Patient immune system
AIDS/HIV
Malnutrition
Alcoholism
Aging
Caseous granulomas resurface
What is a patient at risk of with unchecked TB
Becoming highly contagious
Tubercle rupture
What happens if a tubercle is ruptured
Ruptures into the pleura space allowing air and infected material to flow into the space or the tracheobronchial tree
What is disseminated TB
What it spreads to throughout the body
How does TB bacilli spread
Escape through cavitation and rides through the bloodstream or lymphatics to places with high O2
What is the Ghon Complex
A sign of TB seen on a CXR caused by spread from nodules to the lymph nodes of the hilar
What test are done to diagnose TB
Mantoux Tuberculin skin test
Acid fast stain of sputum
Culture of sputum
CXR
QuantiFERON TB Gold test
Describe the Mantoux test
Injected with a purified protein derivative of TB bacillus
Check in 48-72 hrs
Does a positive Mantoux mean active TB
Not necessarily. It means recent or past infection
How long does it take to receive a TB sputum culture result
6 weeks
Explain a AFB test
Must test negative three times
8-12hrs apart for a rule out
First morning sputum is best
What does the Ziehl-Neelsen stain look like
red bacilli
What does the fluorescent AFB look like
Yellow-green bacilli with dark background
How many drugs and how long does a TB treatment last
2-4 med and 6-9 months
What antibiotics are used for TB
Rifampin
Isoniazid
What do you do if TB bacilli become resistant to one or more of the antibiotics
Add at least three antibiotics
In reference to TB What is (DOT) and who gets it
Direct observation therapy
For patients who are at risk of not complying with medication taking
What QuantiFeron-TB Gold Test
Blood is mixed with synthetic antigen and control and incubated for 16-24 hours
If infected, WBCs will release IFN-gamma
Recommended w/AFB and CXR
