AFB

Question 1

Liquifcation

Answer 1

Step #1

NALC

Question 2

Decontamination

Answer 2

Step #2

NaOH and Oxalic acid

Question 3

Neautralization

Answer 3

Step #3

Buffer or Water

Question 4

Centrifugation

Answer 4

Step #4

3000g x 15-20 minutes

Question 5

Acid Fast

Answer 5

Org is surrounded by mycolic acid layer (hydrocarbons and wax)
Gram Stain does not penetrate wax = ACID FAST

Question 6

Carbol Fuschion

Answer 6

Zich-Neelson: hot (heat removes wax)

Kinyoun: cold (pheynol removes wax)

Question 7

Runyoun Group I

Answer 7

Photochromogens
Yellow pigment when exposed to light
(M. kanasii, M. marinum, M. simiae)

Question 8

Runyoun Group II

Answer 8

Schotochromagens
Pigmented WITHOUT light, gets darker when exposed to light
(M. scrofulaceum, M. gordonae, M. Szulgi, M. Flavescens, M.xenopi, M. thermoresistible)

Question 9

Runyoun Group III

Answer 9

Nonphotochromogens
non-pigmented
(M. avium-intercellulare, M. ulcerans, M.tb, haemophilum, gasti, terrae)

Question 10

Runyoun Group IV

Answer 10

Rapid Growers
Grow is <7 days
M. fortuitum, M. chelonae, abscessus, smegmatis

Question 11

Mycobacterium tuberclosis

Answer 11

Niacin +
Nitrate +
Urease +
Catalase -
Tween 80 Hyrdolysis -

Virulence: Antigen 85 Complex: “walls off” Mtb, high lipid content, grows intracellularly (inhibits phaygocytosis)

ID: PPD, Quantiferon (if infected, patient WBCs release IFN-gamma and amount of IFN-gamma is measured)

TX: Isonaizid, rifampin

Question 12

Mycobacterium bovis

Answer 12

TB in cattle, cats, dogs, swine

Niacin (variable)
Nitrate - 
Catalase -
Urease +
Tween 80 Hydrolysis -

Question 13

Mycobacterium avium complex

Answer 13

Pulmonary disease similar to TB (cough, fatigue, fever)
lymphadenitis
Immunocompromised patients, AIDS
Affects bowels of AIDS patients

Niacin -
Nitrate -
Catalase-
Urease -
Tween 80 Hydrolysis-

Question 14

Mycobacterium kansasii

Answer 14

Pulmonary disease (TX, LA, , FL, CA)

Chronic Cavitary Disease
Infects upper lung lobes with cavitation and scarring
AIDS/immunocompromised

Question 15

Mycobacterium asiaticum

Answer 15

Rarely a pathogen

Question 16

Mycobacterium gastri

Answer 16

Rarely a pathogen

Question 17

Mycobacterium gordonae

Answer 17

Found in tap water and soil
Found often, but not always a pathogen (contam)

Niacin -
Nitrate -
Catalase +
Urease-
Tween 80 Hydrolysis +

Question 18

Mycobacterium haemophilum

Answer 18

Patients with AIDS and Hodgkin’s Disease
Associated with painful swellings, abscessed, subcutaneous nodules
Needs hemoglobin or hemin for growth (CHOC)

grows better at 30 degrees
Niacin-
Nitrate -
Tween 80 -
Catalase -

Question 19

Mycobacterium marinum

Answer 19

Associated with fish/aquariums
Cutaneous infections in humans after contact with water (lesions in life guards; “swimming pool granuloma”)
Grows better at 30

Question 20

Mycobacterium scrofulaceum

Answer 20

cervical lymphadenitis in KIDS “ scrofula” (enlarged nodes in neck)
Treated with drainage, no anti-TB drugs needed

Question 21

Mycobacterium szulgi

Answer 21

Pulmonary disease

Question 22

Mycobacterium terrae Complex

Answer 22

Septic arthritis, synovitis, osteomyelitis

Question 23

Mycobacterium ulcerans

Answer 23

Painless nodules under the skin, ulcer
Grows better at 32

Niacin -
Nitrate -
Catalase +
Urease (variable)
Tween 80 Hydrolysis -

Question 24

Mycobacterium xenopi

Answer 24

Only seen in Southeast England

Lung infections in people with pre-existing conditions (alcoholism,lung disease, diabetes)

Question 25

Mycobacterium chelonae

Answer 25

Found in the environment | Infections in immunocompromised patients

Question 26

Mycobacterium fortuitum

Answer 26

From soil, water, dust Skin and soft tissue infections Associated with infections from long-term use catheters, surgical wounds, injection sites

Question 27

Mtb Stage 1

Answer 27

Droplet nuclei inhaled

Question 28

Mtb Stage 2

Answer 28

Engulfed by macrophages 7-21 days after incubation

Question 29

Mtb Stage 3

Answer 29

T cells activated, releasing cytokines Skin Test + Tubercules form ("cheesy necrosis")

Question 30

Mtb Stage 4

Answer 30

Mtb replicates | Tubercules grow/spread outside lung (extra-pulmonary TB/Military TB.... brain, liver, kidney)

Question 31

Mtb Stage 5

Answer 31

Center of tubercules liquifies Bronchi rupture and form cavity Lesions calcify = "Ghon Complex"

Question 32

Mycobacterium leprae

Answer 32

Leprosy, Hansen’s Disease US reservoir = 9-banded armadillo Grows better at 30 degrees Disease: loss of eyebrows, lesions, ticketed ears/cheeks

Question 33

Grows better at lower temps (28-32)

Answer 33

Ulcerans Marinum Haemophilum Chelonei

Question 34

Grows better at higher temps (42-45)

Answer 34

Xenopi | Thermoresistible

Question 35

PANTA

Answer 35

polymixin B, amphotericin B, naladixic acid, trimethoprim, azlocillin

Question 36

Treatment for NTM infections

Answer 36

Rifampin, Ethambutol, Azithromycin

Question 37

Nocardia

Answer 37

Soil organisms Usually affect immunocompromised No toxins, no virulence factors identified Pulmonary and cutaneous infections Branching GPB, beading partial acid fast positive might grow better using "paraffin bait technique"

Question 38

Nocardia asteroides

Answer 38

pulmonary infections

Question 39

Nocardia brasiliensis

Answer 39

cutaneous infections thorns or slivers after outdoor activity