Acid Fast Bacteria

Question 1

Acid Fast Bacteria

Answer 1

Rod shaped, aerobic
Do not form spores
Resist decolorization by acid or alcohol

Question 2

Mycobacterium tuberculosis

Answer 2

Intracellular organism
Slow growing (12-20hr)
Weakly G(+) cell wall
Resist drying
Sensitive to UV, phenol, hypochlorite, heat
Virulence factor: cord factor, intracellular survival
Growth: Lowenstein-Jensten medium
Aka Koch’s bacillus
CM: Pulmonary Tuberculosis (PTB), Extrapulmonary tuberculosis (EPTB)-bones and tissues,
Tb of the skin, bones, kidney, and other organs
s/s: afternoon fatigue, pm fever, loss of appetite and weight (rapid), cough, hemoptysis (bloody sputum)
Diagnosis o Mantoux test (told) – tuberculin o Purified protein derivative (new)
Treatment: TB Directly Observed Treatment, Shortcourse (TB-DOTS)

Question 3

Mycobacterium leprae

Answer 3

Causes Hansen’s disease aka Leprosy
Found in scrapings from skin or mucous membrane in lepromatous leprosy
Attacks colder tissues of the body (ears, nose, cheeks, scrotum)

Question 4

Two types of Leprae

Answer 4

A. Tuberculoid (TL)
Benign type
CM: blotchy, flat lesions
(+) in lepromin skin test

B. Lepromatous (LL)
CM: disfiguring appearance
(leonine/lion like), thickening of eyebrows, lips, cheeks
Disintegration of boy parts, malignant type
(-) in lepromin skin test

Rx: Dapsone (DOC)
SE: erythema nodosum leprosum