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1
Q

T/F. Mycobacterium are gram neg.

A

F. Positive

2
Q

T/F. Mycobacterium do not have an outer memb

A

T

3
Q

T/F Mycobacterium have mycolic acid in their cell wall

A

T

4
Q

Contributes to the acid fast staining

A

Mycolic acid

5
Q

Gram +, acid fast +, Rod shaped bacteria

A

Mycobacterium

6
Q

Mycobacterium grow in aerobic/anaerobic conditions

A

Aerobic

7
Q

Do mycobacterium survive in the environment well?

A

yes

8
Q

Genus of historic importance in developed countries because of human and bovine tuberculosis

A

Mycobacterium

9
Q

What spp of mycobacterium cause Johne’s Dz

A

M. avium subsp. paratuberculosis

10
Q

Mycobacterium are intra/extracellular pathogens?

A

Facultative intracellular

11
Q

What type of immunity protects animals against Mycobacterium?

A

Cellular immunity (Th1 resp.)

12
Q

What is the pathogenesis of mycobacterium spp.

A

Chronic bacterial infections and granulomatous inflam.

13
Q

Mycobacterium are facultative intracellular pathogens of _______.

A

Macrophages

14
Q

What are the 3 virulence factors of Mycobact.

A
  1. Lipid rich- protection from IS
  2. Lipoarabinomannan
  3. Cell protein antigens
15
Q

Virulence factor of mycobac. that inhibits the phagosome from fusing with the lysosome

A

Lipoarabinomannan

16
Q

What are the 3 spp. of mycobac. that are obligate pathogens?

A
  1. M. tuberculosis complex
  2. M. avium subsp. paratuberculosis
  3. M. leprae
  4. M. lepraemurium
17
Q

Which spp of Mycobac. causes mammalian TB?

A

M. TB complex:

  1. M. tuberculosis
  2. M. bovis
  3. M. africanum
  4. M. microti
18
Q

Which spp. of mycobac. causes Avian TB?

A

M. avium subsp. avium

19
Q

Which spp of mycobac. causes Leprosy?

A

M. leprae- human

M. lepraemurium- cat

20
Q

Which spp. of mycobac, forms caseous granulomas

A
  1. M. tuberculosis

2. M. bovis

21
Q

What is the transmission of TB?

A

Inhalation and ingestion

22
Q

What is the pathogenesis of TB?

A
  1. Local multiplication
  2. uptake by macrophages
  3. Migration to lymph node
  4. lymphadenitis
23
Q

_____ IR is important in the destruction of bacilli

A

Cell mediated

24
Q

What type of hypersensitivity is seen with TB?

A

type 4 (delayed type)

25
Q

The classic lesion of TB. Well organized granulomas of varying sizes

A

Tubercles

26
Q

What are the two possible centers of tubercles?

A
  1. Hard tubercle: solid packed with epithelioid macrophages

2. Soft Tubercle: caseous necrosis

27
Q

Who is the main reservoir for M. tuberculosis

A

Humans

28
Q

What spp. are effected by M. tuberculosis

A

humans, dogs, cats, pigs, primates

29
Q

What are some methods of diagnosing M. tuberculosis

A
  1. Radiographs
  2. AFB staining, culture, PCR of sputum
  3. TB test (mantoux test)
30
Q

T/F. TB is a treatable and cureable Dz

A

T

31
Q

What is the standard treatment of TB?

A

6 months course of antimicrobial drug combinations (mix of primary and secondary drugs)

32
Q

What are the 4 primary TB drugs?

A
  1. Isoniazid
  2. Rifamycins
  3. Ethambutol
  4. Pyrazinamide
33
Q

What are teh 2 categories of secondary drugs used to tx TB?

A
  1. Aminoglycosides

2. Fluoroquinolones

34
Q

Why must you use combination drug therapy when treating TB?

A
  1. bacteria n lesion can be intra or extracellular
  2. Grow in log pahse and exhibit quiescent phase
  3. Drug resistance
  4. poor distribution to walled off lesions
35
Q

What is MDR TB?

A

Multidrug resistant TB- resistant to at least isoniazid and rifampin

36
Q

What is XDR?

A

Extensively Drug resistant TB- Resistant to isoniazid and rifampin, plus any fluoroquinolone and at least one of the 3 inj second line drugs

37
Q

What is the human vaccine for TB?

A

BCG (bacillus Calmette Guerin)

38
Q

What Mycobac. causes zoonotic TB?

A

M. bovis

39
Q

Transmission of M. bovis

A

ingestion
inhalation
contact with mucus memb

40
Q

What is the main portal of entry for M. bovis

A

GIT

41
Q

M. bovis is maintained primarily in _____ spp., but has the broadest host range of all TB organisms

A

Bovine

42
Q

how long can M bovis survive outside of the host?

A

few weeks

43
Q

T/F. there are significant differances in M bovis and M. tuberculosis infections

A

F. indistinguishable

44
Q

____ transmission of M bovis is most common among cattle

A

Aerosol

45
Q

T/F. M bovis can be spread in milk

A

T

46
Q

list some Dx of M bovis

A
  1. TB test
  2. Gamma IFN blood test
  3. Clinical dz + Histopathology
  4. Direct Acid-fast stain
  5. Culture
  6. DNA based methods
47
Q

What is the tuberculin hypersensitivity skin test?

A

inj. animal with M. bovis protein, look for swelling of inj site in 72 hrs.

48
Q

T/F. cows infected with M. bovis can be treated and cured

A

F. not recommended to tx, culling is best option

49
Q

T/F. there are no vaccines available for M bovis

A

T

50
Q

What are the 5 elements of bovine TB eradication programs?

A
  1. Dz surveillance
  2. Pre and post movement cattle testing
  3. Removal of cattle exposed to TB
  4. Tracing source
  5. Wildlife control
51
Q

A chronic, progressive granulomatous enteritis in cattle infected with M. avium subsp paratuberculosis

A

Johne’s Dz

52
Q

Who is the primary host of Johne’s Dz

A

Cattle

53
Q

What is the pathogenesis of Johnes Dz

A

ingestion of contaminated milk or in utero. found in macrophages in the intestine and ln. will lay dormant for 2-5 years

54
Q

symptoms of Johne’s Dz

A

diarrhea and wt. loss

55
Q

3 Dx methods for paratuberculosis

A
  1. Acid fast stain
  2. Culture
  3. PCR
56
Q

Dx method for Johne’s dz commonly used in cattle herds to detect humoral immune response to MAP

A

ELISA

57
Q

When do false negative ELISAs occur when testing for Johne’s Sz

A

In advanced stages of dz due to anergy

58
Q

How do yo treat Johne’s Dz

A

Not recommended to tx

59
Q

List some prevention measures for Johne’s dz

A
  1. culling infectd
  2. detection of asymptomatic carriers
  3. Separation of calves at birth
  4. pasture rotation
60
Q

Is their a vaccine available for Johne’s dz

A

Yes, restricted due to reactions

61
Q

In Johne’s dz who is most susceptible?

A

Young

62
Q

What 3 subsp. of Mycobacterium avium intracellular complex?

A
  1. subsp. avium
  2. subsp. sylvactium
  3. subsp. hominisuis
63
Q

disease caused by M. ulcerans

A

Buruli ulcer

64
Q

one of the fequent mycobacteral diseases in humans in certain geographic regions

A

Buruli ulcer

65
Q

What causes tissue necrosis in buruli ulcer?

A

cytotoxin mycolactone

66
Q

Mycobacterium that causes leprosy or hansen’s dz

A

M. leprae

67
Q

how is M leprae shed?

A

through the nose, not the skin

68
Q

What is the only known animal reservoir for M leprae?

A

9 banded armadillo

69
Q

What is the diff. between tuberculoid leprosy and lepromatous leprosy?

A

TL (paucibacillary)- few acid fast positive bacilli in the lesion
LL- (multibacillary)- no cell mediated response, severe dz with numerous acid fast positive bacilli

70
Q

What is M. lepraemurium

A

Feline and murine leprosy

71
Q

What does it mean when an organism is fastidious

A

hard to culture

72
Q

what is the result of M lepraemurim infection

A

granulomatous dermatitis and panniculitis

73
Q

How do you dx M lepraemurium?

A

Direct staining
culture
biopsy and histopathy
PCR

74
Q

In Gram stain of M. lepraemurium positive/negative stained bacilli are generally observed

A

negative

75
Q

T/F In a gram stain fof M lepraemurium gram negative bacilli are commonly observed

A

F. negative stained not gram negative

76
Q

How do you tx M. lepraemurium

A
  1. surgical excision

2. Rifampin, Clarithromycin, Clofazimine

77
Q

What abx can be given to dogs with M. lepraemurium?

A

Doxycycline

78
Q

What are the 2 categories of Saprophytic Mycobacterium

A
  1. rapid growing

2. slow growing

79
Q

type of mycobacterium that causes chronic, non-healing cutaneous lesions that do not respond to common antibacterial tx

A

Saprophytic mycobacterium