Mycobacterium Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

Generally, what infections do mycobacterium cause?

A

pulmonary and extrapulmonary infections

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Mycobacteria are acid-fast. Why?

A

because of their high lipid content in their cell walls

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How do mycobacteria show up on gram stain?

A

they are gram negative rods

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What type of organisms are Mycobacteria in regards to oxygen?

A

they are aerobic but they grow better in CO2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What type of media is typically used to grow Mycobacteria?

A

media that is egg-based

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What disinfectants are mycobacteria resistant to?

A

halogen and quaternary ammonium disinfectants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What can kill mycobacteria?

A

phenol and substituted cresylic compounds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Are infections caused by Mycobacteria acute or chronic?

A

chronic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What type of parasites are Mycobacteria?

A

facultative intracellular parasites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What type of mycobacteria are killed by phagocytic cells and what type kill phagocytic cells?

A

saprophytic; pathogenic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Where in the cell are mycobacteria found?

A

in the cytoplasm of the macrophage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

When mycobacteria rypture macrophages and adjoining cells are infected, what is formed as a result?

A

tubercles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Where are lesions from mycobacteria typically localized?

A

in the lungs, spleen, or liver

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are some immune mechanisms and proposed mechanisms by which mycobacteria are able to resist or alter the immune response?

A
  1. promote phagosome-lysosome fusion 2. Aggregate macrophages into epithelioid granulomas to restrict and contain mycobacteria 3. processing and presentation of bacterial antigens 4. Activation of T cells to control infection 5. increase microbicidal capacity of the granuloma by recruiting effector T cells to it
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Why is the high lipid content of Mycobacteria important in their resistance to killing?

A

because they produce a variety of phospholipids, glycolipids, and sulfur-containing glycolypids that may interfere with host immune mechanisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the immune response to Mycobacterium?

A

it is largely cellular and almost entirely mediated by macrophages. Leukocytes have been known to release reactive nitrogen and oxygen intermediates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is Freund’s complete adjuvant?

A

a type of mineral oil that contains killed Mycobacterium smegmatis or M. phlei, but it is not used commercially due to lesions associated with the injection site

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How is mycobacteria diagnosed?

A

since mycobacteria induces a delayed-type hypersensitivity reaction, the DTH reaction (intradermal skin test) is used to expose tubercle bacilli associated with mycobacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What antigen is used in the DTH reaction?

A

tuberculin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the different types of tuberculins used in the DTH test?

A

PPD (purified protein derivative) and OT (old tuberculins)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How are PPDs prepared?

A

by growing the organism on synthetic culture media, autoclaving, removing the cells, and precipitating the proteins with either ammonium sulfate or TCA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How are OTs prepared?

A

by growing bacilli on synthetic culture media

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What type of tuberculins is used the majority of the time?

A

PPDs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What do drugs used to treat mycobacteria usually contain?

A

isoniazid and rifampin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What species does Mycobacterium tuberculosis infect?

A

primates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What specific disease does Mycobacterium tuberculosis cause?

A

tuberculosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What famous scientist is associated with Mycobacterium tuberculosis?

A

Robert Koch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What other species does Mycobacterium tuberculosis infect?

A

zoo animals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

In humans, tuberculosis is most often _______ in nature.

A

pulmonary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What lesions are associated with tuberculosis in humans?

A

lung lesions or cavitations that can develop and progress to the point that large blood vessels are compromised and the patient can bleed to death quickly; lesions occur in the vertebral column, kidneys, bladder, larynx, and other sites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

How is tuberculosis treated?

A

six months of anti-TB drugs (1/3 kilogram a day)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What is the resistant strain of tuberculosis called?

A

XDR-TB

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is the recommended treatment for extensive drug resistant tuberculosis (XDR-TB)?

A

removal of lungs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is the name of the most widely used human immunizing agent for TB in the world?

A

Bacille Calmette Guerin (BCG)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What does BCG contain?

A

a weakened live strain of Mycobacterium bovis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Who is BCG effective for?

A

infants and children

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

How do immunized individuals respond to PPD tubergulins?

A

positive - so it is hard to determine if they are immunized

38
Q

What disease does Mycobacterium bovis cause and in what species?

A

tuberculosis in cattle, pigs, cats, horses, primates, dogs, sheep, and goats

39
Q

What chemical in media inhibits the growth of Mycobacterium bovis?

A

glycerol

40
Q

How long does it take for Mycobacterium bovis to grow on media?

A

3-4 weeks

41
Q

What do cultures of Mycobacterium bovis look like?

A

rough and waxy

42
Q

How is Mycobacterium bovis destroyed?

A

via pasteurization or direct sunlight

43
Q

What species are making it difficult for Mycobacterium bovis eradication in the US?

A

white-tailed deer and farmed elk

44
Q

How is Mycobacterium bovis transmitted?

A

primarily through a respiratory route and a small percentage of infections occur through the ingestion of milk, congenitally, and possibly venereally

45
Q

What is the pathogenesis of Mycobacterium bovis?

A

once the individual is infected, the organism is ingested by macrophages, grows in the macrophage, kills and lyses it, then tuburcles made up of organism, macrophages, giant cells, and other inflammatory cells are encapsulated. The organism then travels through the lymph creating secondary metastasis

46
Q

What is the immune response to Mycobacterium bovis?

A

primarily cell mediated immune responses that are effective about 4 weeks following the infection

47
Q

How is Mycobacterium bovis diagnosed?

A

with the delayed type hypersensitivity (skin test) with PPD tuberculin (caudal fold test)

48
Q

Explain the testing process within a herd of a suspect bovine tuberculosis patient.

A

A normal vet will do a caudal fold test, then they will report it to the state, then the state will do a comparative cervical test on that individual and if it comes back positive they will do a single cervical test on the entire herd

49
Q

How are exotic ruminants diagnosed for Mycobacterium bovis?

A

Cervid TB Stat-Pak test which is a serologic test - only need to handle animals once

50
Q

What is MAC?

A

Mycobacterium avium complex

51
Q

What disease does Mycobacterium avium cause and in what species?

A

tuberculosis in avian species and swine

52
Q

Which Mycobacterium avium species are more virulent for birds but can produce disease in swine and other animals?

A

Serotypes 1, 2, and 3

53
Q

How are serotypes 1, 2, and 3 of Mycobacterium avium transmitted?

A

by ingestion of contaminated feces or soil in which organisms survive for a long time

54
Q

What lesions are associated with serotypes 1, 2, and 3 of Mycobacterium avium?

A

lesions in bones, joints, liver, spleen, and the intestinal tract

55
Q

What do lesions in the intestinal tract due to serotupes 1, 2, and 3, of Mycobacterium avium look like?

A

nodules that open and discharge into the lumen of the intestine

56
Q

What serotypes of Mycobacterium avium typically cause disease in swine?

A

serotypes 1, 2, 4, and 8

57
Q

What lesions are associated with serotypes 1, 2, 4, and 8 of Mycobacterium avium in swine?

A

foci in the mandibular and mesenteric lymph nodes and occasionally in the intestinal tract; lesions can occur in the liver and elsewhere

58
Q

How are serotypes 1, 2, 4, and 8 of Mycobacterium avium transmitted in swine?

A

via ingestion

59
Q

What disease is Mycobacterium leprae associated with and in what species?

A

leprosy in humans and armadillos

60
Q

How is Mycobacterium leprae transmitted?

A

via respiratory to respiratory

61
Q

What disease is associated with Mycobacterium lepraemurium and in what species?

A

leprosy-like disease in cats and rats

62
Q

What lesions does Mycobacterium marinum cause and in what species?

A

swimmin pool granuloma on the arms and legs of humans and granulomatous lesions in cold-blooded aniimals

63
Q

How do humans become infected with Mycobacterium marinum?

A

the organism travels from a site of trauma on an extremity that has contact with water

64
Q

What occurs to Mycobacterium marinum when grown in the presence of light?

A

it produces a yellow pigment

65
Q

What lesions does Mycobacterium kansasii cause and in what species?

A

lymph node lesions in cattle, deer, and swine

66
Q

Mycobacterium kansasii is the second leading cause of ____-_________ mycobacterial _______ and causes both ______ and occasionally ________________ lesions in humans.

A

non-tuberculosis; infections; pulmonary; extrapulmonary

67
Q

Mycobacterium kansasii is a _____ grower and is ________.

A

slow; photochromogenic

68
Q

What lesions are associated with Mycobacterium fortuitum and in what species?

A

it produces pulmonary disease in dogs and humans

69
Q

As compared to other Mycobacterium species, Mycobacterium fortuitum is _____ growing?

A

fast

70
Q

What species does Mycobacterium chelonae typically infect?

A

swine, cold-blooded animals, and humans

71
Q

What type of lesions does Mycobacterium chelonae cause in swine and cold-blooded animals?

A

lymph node lesions

72
Q

What type of lesions does Mycobacterium chelonae cause in humans?

A

skiin lesions associated with patients receiving porcine heart valve transplants

73
Q

True or False: Mycobacterium chelonae is a fast growing bacteria.

A

TRUE

74
Q

What is MAP?

A

Mycobacterium avium subspecies paratuberculosis

75
Q

What does MAP cause?

A

Johne’s disease

76
Q

What lesions does Johne’s disease cause?

A

chronic proliferative enteritis

77
Q

What species does Johne’s disease affect?

A

cattle, sheep, goats, camels, llamas, and some wild ruminants

78
Q

What is the morphology of MAP?

A

smaller than the tubercle bacilli; short rod

79
Q

Where is MAP found in infected species?

A

in tissues and feces

80
Q

How long does it take for MAP to grow?

A

4-16 weeks on solid media

81
Q

What compound is required for primary isolation of MAP?

A

mycobactin - an iron chelating compound

82
Q

Where is MAP found in the environment?

A

in soil

83
Q

What can kill MAP?

A

moderate heat, 5% formalin or 5% phenol

84
Q

How is MAP transmitted?

A

from feces of individuals in the later stage of the disease to calves by ingestion; in utero ingestion is also found

85
Q

What is the pathogenesis of MAP?

A

once ingested, the organism penetrates into the epithelium of the ileum and colon and is phagocytosed by macrophages, the organism multiplies within the macrophages and stimulates a granulomatous response that spreads through the intestines and regional lymph nodes. The intestine becomes very thickened due to proliferation of epitheliod cdells

86
Q

What are the symptoms of clinical disease in cattle affected with Johne’s disease?

A

intermittent diarrhea and emaciation

87
Q

How is MAP diagnosed?

A

PCR, culture, serologic responses, acid fast stain, and delayed type hypersensitivity testing

88
Q

When diagnosing MAP, what are PCRs done on (what organic material)?

A

feces

89
Q

What is the additive used to detect MAP in DTH?

A

johnin which is produced from culture filtrates of MAP

90
Q

Is there treatment for MAP?

A

No - it is not attempted

91
Q

How is Johne’s disease controlled?

A

immunization only in populations that have confirmed cases

92
Q

Where is the Johne’s vaccination injected?

A

into the brisket of young calves