Mycobacteria

Question 1

General growth rate of Mycobacteria

Answer 1

Slow
16-18 hours for one division

Question 2

Why is Mycobacteria Acid Fast?

Answer 2

Large amounts of lipids in cell wall

Question 3

Aerobic/Anaerobic?
Motile/NonMotile?
Spore forming/nonspore forming?

Answer 3

Aerobic
Non motile
Non spore forming

Question 4

Shape of Mycobacteria

Answer 4

Rod shaped
Beaded

Question 5

Virulence mechanisms of Mycobacteria?

Answer 5

Intracellular survival resisting phagocytic acidification

Question 6

Bodily defenses against Mycobacteria?

Answer 6

Delayed type hypersensitivity
Acquired cellular immunity

Question 7

TB most often route of entry?

Answer 7

Respiratory

Question 8

Mode of infection for TB

Answer 8

Alveolar macrophages eat TB, T-Cells arrive 4-6 weeks later, bacteria eliminated –> primary lesion heals or hard tubercle/granulomar forms if bacteria not eliminated

Question 9

Who develops miliary TB?

Answer 9

Young kinds, immunosuppressed, old people

Question 10

Factors contributing to reactivation of TB

Answer 10

Malnutrition
Alcoholism
Homelessness
Immunosuppressed
AIDS
Incarceration

Question 11

Pathology of Tuberculosis

Answer 11

Tubercle or Caseation
Tubercle - Physical walling off of TB
Caseation - Cheese-like necrotic tissue from the original alveolar lesion

Question 12

Other sites for TB

Answer 12

Cervical lymphadenitis
Pleuritis
Pericarditis
Synovitis
Meningitis
Skin
Miliary tuberculosis (disseminated)
Spine

Question 13

Lab features of TB

Answer 13

Slow growing
Non-pigmented, rough
Serpentine cording in liquid media

Question 14

Key lab test results for TB

Answer 14

Niacin pos
Nitrate pos
68C Catalase neg

Question 15

Hansen’s Disease AKA

Answer 15

Leprosy

Question 16

How is Leprosy transferred?

Answer 16

From the nose

Question 17

Incubation period of M. leprae

Answer 17

Years

Question 18

Symptoms of Leprosy

Answer 18

Anesthetic skin lesions
Peripheral neuropathy
Nerve thickening
Deformation

Question 19

How is Leprosy diagnosed?

Answer 19

Clinical symptoms, acid fast, armadillos

Question 20

What does M. leprae grow on?

Answer 20

Cannot grow on artificial media

Question 21

Tuberculoid Leprosy

Answer 21

More localized,
More serious
Not very infection

Question 22

Lepromatous Leprosy

Answer 22

Disseminated
More infectious

Question 23

How is Leprosy treated?

Answer 23

Curable with antibiotics
Non-infectious after 3 days
Treatable with thalinomide

Question 24

Slow growing bacteria other than TB

Answer 24

Avium
kansasii
marinum
szulgai
scrofulaceum
ulcerans

Question 25

Most commonly isolated Mycobacteria sp.?

Answer 25

M. avium

Question 26

Pathogenicity of avium

Answer 26

Low, except AIDS/immunosuppressed

Question 27

Diseases M. avian causes

Answer 27

TB-like pulmonary disease Cervical lymphadenitis Disseminated Chrons Disease (M. avium paratuberculosis)

Question 28

Colony lab features of M. avium

Answer 28

Slow-growing Non-pigmented Heterogenous morphology

Question 29

Biochemical reactions M. avium

Answer 29

HS Catalase pos T2H pos Tellurite pos Pyrazinamidase

Question 30

Yellow bacillus

Answer 30

M. kansasii

Question 31

Source of M. avium

Answer 31

Environment Animals

Question 32

Sources of M. kansasii

Answer 32

Environment Tap-water

Question 33

2nd most common Mycobacteria

Answer 33

M. kansasii

Question 34

Diseases caused by M. kansasii

Answer 34

Chronic pulmonary disease Skin infection Disseminated in immunosuppressed

Question 35

Lab characteristics of M. kansasii

Answer 35

Pigmented Photochromogen Slow-grower

Question 36

Biochemical reactions for M. kansasii

Answer 36

T2H pos Nitrate pos 68C Catalase pos Tween pos Pyrazinamidase neg

Question 37

M. marinum sources

Answer 37

Fresh and salt water from fish Gets into a cut

Question 38

Ex. of cases of M. marinum

Answer 38

Fish-tank granuloma Watermen (sporotrichosis-like, wound travels up limb) Swimming pool granuloma in life guards

Question 39

Pathogenicity of M. marinum

Answer 39

Lesion that is hard and lumpy (sporotrichosis)

Question 40

Lab characteristics of M. marinum

Answer 40

Slow growing photochromogen --> dark yellow

Question 41

Biochemicals M. marinum

Answer 41

Tween pos Pyrazindamidase pos urease pos

Question 42

M. szulgai sources

Answer 42

Water Soil

Question 43

M. szulgai disease

Answer 43

Chronic pulmonary disease Disseminated in immunosuppressed

Question 44

Lab characteristics of M. szulgai

Answer 44

Photochromogen at 25C Scrotochromogen at 37C

Question 45

Biohcemicals for M. szulgai

Answer 45

T2H pos Nitrate pos 68C catalase pos Pyrazinamidase pos

Question 46

M. scrofulaceum sources

Answer 46

Dairy products Soil Water

Question 47

M. scrofulaceum disease

Answer 47

Cervical lymphadenitis in kids Pulmonary disease

Question 48

Lab characteristics of M. scrofulaceum

Answer 48

Slow grower Scrotochromogen

Question 49

Biochemicals M. scrofulaceum

Answer 49

T2H pos 68C Catalase pos

Question 50

M. ulcerans sources

Answer 50

Tropical wetlands Diseases in wild animals

Question 51

(in developing nations) 3rd most frequent Myco. infect

Answer 51

M. ulcerans

Question 52

M. ulcerans lab characteristics

Answer 52

Hard to grow (lower temperature, heat sensitive) No pigment 8-12 week incubation

Question 53

M. ulcerans biochemical results

Answer 53

T2H pos 68C Catalase pos

Question 54

M. forticum Source

Answer 54

Water Soil Dust

Question 55

M. forticum diseases

Answer 55

Post-Surgical wounds Traumatic wounds

Question 56

M. forticum lab characteristics

Answer 56

Nonpigmented colonies Multi-Lobed colonies Growth on Modified MAC (no crystal violet)

Question 57

Biochemicals M. forticum

Answer 57

Nitrate pos Iron uptake pos

Question 58

M. chelone sources

Answer 58

Environment, exactly where is unknown

Question 59

M. chelone diseases

Answer 59

Nodules in skin w draining lesions Cystic Fibrosis patients

Question 60

Slowest growing organism of Rapid Growing Mycobacteria?

Answer 60

M. chelone

Question 61

Lab characteristics of M. chelone

Answer 61

Likes lower temps Off-white smooth colonies

Question 62

Biochemicals M. chelone

Answer 62

Nitrate neg Iron uptake neg

Question 63

M. abscesses sources

Answer 63

Tap water

Question 64

M. abscesses diseases

Answer 64

Nosocomial, related to surgery Environmental, related to trauma Chronic Lung disease (CF)

Question 65

M. abscesses lab characteristics

Answer 65

Non-pigmented Off-white Irregular Smooth or Wrinkled

Question 66

M. abscesses biochemicals

Answer 66

Similar to M. chelone RFLP Most reliable

Question 67

M. gordonae sources

Answer 67

Tap water bacillus soil

Question 68

Most common non-pathologic species

Answer 68

M. gordonae

Question 69

Lab characteristics of M. gordonae

Answer 69

Scotochromogen Yellow to Orange Smooth

Question 70

Biochemicals M. gordonae

Answer 70

Nitrate neg

Question 71

Species of Mycobacteria Tuberculosis Complex

Answer 71

M. tuberculosis M. africanum M. bovis

Question 72

What prevents TB from bovis?

Answer 72

Pasteurization Herd control programs

Question 73

M. avium complex

Answer 73

M. avium M. paratuberculosis M. intracellulare