Mycobacteria Flashcards
What is the feature of Mycobacteria ?
1- Not stained by Gram stain
2- acid-fastness: due to high lipid content (waxy mycolic acid )
3- They are stained by Ziehl-Neelsen stain (Z.N.)
Wnat is the feature of Mycobacterium tuberculosis ?
1- Acid- fast bacilli, slender
2- Non-motile, non-capsulated and non-spore forming.
3- obligate (strict) aerobes.
4- Virulent strains grow in parallel groups called cords (due to cord factor)
What is the initial infection site of Mycobacterium tuberculosis ?
apex of lung alveoli
Mycobacterium tuberculosis is survive and multiply ?
intracellular inside the macrophages & RES
What is the risk factors of Mycobacterium tuberculosis ?
AIDS patients due to Endogenous reactivation of tuberculosis
What is the Systemic effects of tuberculosis (TB) ?
Night fever and sweating , Loss of weight
What is the Culture of Mycobacterium tuberculosis ?
1- Lowenstein Jensen’s medium (Egg based solid media)
2- Commercial broth systems Automated BACTEC
What is the test of latent TB infection diagnosis?
Tuberculin Skin Test (TST)
What are the risk groups if the induration is ≥ 5 mm ?
1- Recent contacts of a case of TB.
2- Immunosuppressed as HIV patients and organ transplant recipients.
What is the vaccine of Mycobacterium tuberculosis ?
Bacille Calmette Guerin (BCG) vaccine. Type: live-attenuated
TB is killer of youth all over the world, due to ?
Increased of HIV, multidrug resistant strains .
Infection of Mycobacterium leprae is due to ?
close contact
What is the causative organism of leprosy ?
1- Tuberculoid type (immune response viaTH1)
2- Lepromatous type (immune response via TH2)
What is the stain of Mycobacterium leprae ?
modified Ziehl Neelsen (MZN)
lepromin test is negative in the ?
Lepromatous type (immune response via TH2)
