Mycobacteria

Question 1

why do these cells need acid fast stain?

Answer 1

cell wall has high lipid content, rich in mycolic acids

Question 2

what are the environmental requirements?

Answer 2

strictly aerobic
increased CO2 enhance growth
require 2-6 weeks incubation

Question 3

what organisms are a part of the mycobacterium tuberculosis complex?

Answer 3

tuberculosis
bovis
africanum
microti

Question 4

what are some characteristics of the m. tuberculosis complex?

Answer 4

all cause tuberculosis
slow growers
nonpigmented

Question 5

what are symptoms of primary tuberculosis?

Answer 5

productive cough
low grade fever
night sweats
fatigue
anorexia
weight loss

Question 6

how is tuberculosis transmitted?

Answer 6

air droplets

Question 7

what is skeletal TB of the spine called?

Answer 7

Pott disease

Question 8

what is the treatment for tuberculosis?

Answer 8

9 month course of isoniazid and rifampin

Question 9

what causes treatment failures?

Answer 9

patient noncompliance

drug resistance

Question 10

what organism has serpentine cords on middlebrook after 5 - 10 days

Answer 10

M. tuberculosis

Question 11

how long does it take for M. tuberculosis to grow on LJ

Answer 11

14 -28 days at 37

Question 12

niacin +
nitrate +
inhibited by NAP
catalase -
Tween 80 >5 days

Answer 12

tuberculosis

Question 13

niacin -
nitrate -
tween 80 > 5 days

Answer 13

bovis

Question 14

what groups make up the NTM?

Answer 14

photochromogens
scotochromogens
non photochromogens
rapid growers

Question 15

what organisms are photochromogens?

Answer 15

kansasii
marinum
asiaticum

Question 16

characteristics of photochromogens

Answer 16

dark = buff
light = pigmented
potential pathogens - pulmonary disease

Question 17

what photochromogen causes cutaneous disease after exposure to contaminated water

Answer 17

marinum

Question 18

what organisms are scotochromogens

Answer 18

gordonae
scrofulaceum
szulgai

Question 19

characteristics of scotochromogens

Answer 19

pigmented in light and dark

most nonpathogenic

Question 20

what organisms are nonpathogenic nonphotochromogens

Answer 20

terrae
triviale
nonchromogenicum
gastri

Question 21

what organisms are rare pathogens in nonphotochromogen group?

Answer 21

shimoidei
celatum
xenopi
ulcerans

Question 22

what organisms are the most common pathogens in the nonphotochromogen group?

Answer 22

mycobacterium avium complex

avium, intracellulare

Question 23

how is the MAC spread?

Answer 23

inhalation or ingestion

Question 24

what is the reservoir for MAC?

Answer 24

water

Question 25

what organisms are rapid growers?

Answer 25

fortuitum chelonae smegmatis

Question 26

what organism causes leprosy (hansens disease)?

Answer 26

leprae

Question 27

how is leprosy transmitted?

Answer 27

inhalation | person to person contact

Question 28

photo nitrate + niacin - Tween 80 < 5 days

Answer 28

kansasii

Question 29

photo nitrate - niacin V Tween 80 < 5 days

Answer 29

marinum

Question 30

scoto niacin - nitrate -

Answer 30

scrofulaceum

Question 31

characteristics of m. leprae

Answer 31

cannot be grown in vitro only cultivate in armadillos and mouse footpads optimal growth temp 30

Question 32

what temperature is required for marinum culture

Answer 32

30 - 32 for 7 -21 days

Question 33

Specimens that require digestion

Answer 33

Sputum and other specimens with normal flora

Question 34

Incubation requirements

Answer 34

35 | 5 - 10% CO2

Question 35

Incubation period for slow growers

Answer 35

2 - 6 weeks

Question 36

Ziehl neelsen: Primary stain Decolorizer Counterstain

Answer 36

Carbolfuschin Acid alcohol Methylene blue

Question 37

What does ziehl neelsen stain require

Answer 37

Heat

Question 38

Kinyoun: Primary stain Decolorizer Counterstain

Answer 38

Carbolfuschin Acid alcohol Methylene blue

Question 39

Fluorochrome: Primary stain Decolorizer Counterstain

Answer 39

Auramine-rhodamine Acid alcohol Potassium permanganate

Question 40

organisms that are niacin -

Answer 40

tuberculosis | simiae

Question 41

nitrate + organisms

Answer 41

``` tuberculosis kansasii szulgai fortuitum flavescens ```

Question 42

tween 80 +

Answer 42

kansasii (6 hours) | gordonae

Question 43

urease +

Answer 43

scrofulaceum gastri bovis

Question 44

scoto only positive for Tween 80 and heat stable catalase

Answer 44

gordonae

Question 45

what is the only thing M. avium-intracellulare positive for?

Answer 45

pyrazinamidase

Question 46

what patients are at increased risk of tuberculosis

Answer 46

patients with diminished cell mediated immunity

Question 47

What about the cell wall allows mycobacterium to resist decolorization

Answer 47

Lipids and mycolic acid

Question 48

Safety requirements

Answer 48

BSL3 PPE tb test every year Separate room

Question 49

Best specimen for sputum

Answer 49

First morning deep expectorated cough

Question 50

What organism is being looked for in fecal specimens

Answer 50

Avium-intracellulare

Question 51

What condition is avium- intracellulare associated with

Answer 51

AIDS

Question 52

Reagents for decontamination

Answer 52

N-acetyl-L-cysteine Dithiothreitol 2% NaOH 4% NaOH

Question 53

What does digestion of sputum do

Answer 53

Split disulfide bonds in mucin

Question 54

Primary host defense in tuberculosis

Answer 54

Cell mediated immunity

Question 55

How long does it take for a healthy person to show signs of tuberculosis infection

Answer 55

2 weeks - 3 months

Question 56

What forms granulomas in TB

Answer 56

T cells and macrophages

Question 57

Tap water bacillus

Answer 57

Gordonae

Question 58

preferred carbon source

Answer 58

glycerol

Question 59

mucolytic reagent

Answer 59

N-acetyl-L-cystine-NaOH

Question 60

rhodamine staining: potassium permanaganate function

Answer 60

quenching reagent

Question 61

why must middlebrook media be stored in the dark?

Answer 61

exposure to light may cause formaldehyde production

Question 62

method used to process specimens contaminated with pseudomonas

Answer 62

oxalic acid

Question 63

presumptive diagnosis of hansens disease

Answer 63

detect weakly acid fast bacilli in infected tissue

Question 64

nonchromogen grows best at 42 | highly resistant to antibiotics

Answer 64

xenopi

Question 65

how are intracellulare and avium differentiated?

Answer 65

DNA probe

Question 66

organism that does not fluoresce on fluorochrome stain

Answer 66

fortuitum