Microbiology: Acid-Fast Organisms Flashcards
What does the genus mycobacterium have as its outer layer?
glycocalyx
How easy is it to stain a mycobacterium?
difficult to stain
What kind of disease is caused by a mycobacterium in terms of transmission?
zoonotic
What are the most common mycobacterium strains?
- M. tuberculosis
- M. bovis
- M. avium
What kind of organism is mycobacterium?
Shape?
O2 tolerance?
- obligate aerobe
- slender rod
- acid-fast
What is the causative agent of tuberculosis?
Mycobacterium tuberculosis
M. bovis
M. avium
Where can mycobacterium survive?
can survive for weeks in dried sputum and is very resistant to chemical antimicrobials
How is mycobacterium transmitted?
by inhalation
How do most healthy people react to a mycobacterium exposure?
most people defeat a potential infection with activated macrophages
What happens if a person’s exposure turns into an infection?
the host isolates the pathogen in a walled off lesion called a tubercle
Where are tubercles located?
in the lungs
What happens when the disease is stopped?
the lesions will slowly heal and become calcified in the lungs
What happens if you recovered from a mycobacterium infection but your immune system is weakened by something else?
What is this called?
- tubercles break down and release virulent bacilli into the airways and cardiovascular system
- miliary tuberculosis
How can healed tubercles be seen in the body?
on an x-ray
What are tubercles also called?
ghon complexes
What is another name for miliary tuberculosis?
consumption
What are the symptoms of miliary tuberculosis?
- weight loss
- coughing with blood
- general loss of vigor
How is miliary tuberculosis treated?
a variety of drugs are available but long term therapy is required
Why are there so many strains of drug resistant mycobacterium?
- people don’t continue taking their antibiotics long term
- it can take years to get rid of this infection and people are not willing to do this
Why is miliary tuberculosis called consumption?
the body’s remaining defenses are overwhelmed
