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Flashcards in Mycobacterium Deck (80):
1

mycobacterium has very long and complex ____

mycolic acid 

2

is Mycobacterium reportable?

YES!- hugely important must report

3

Mycobacterium has a very _____ cell wall and is acid fast ____

lipid rich, acid fast positive 

4

Does mycobacterium form spores?

no- it is non spore forming 

5

True/False: Mycobacterium has flagella and capsule 

False: Flagella and capsule are ABSENT from mycobacterium 

6

True/False: Mycobacterium does not survive in the environment for very long 

False: they are very heary and survive for very long periods of time in the environment due to their very lipid rich cell wall 

7

Is mycobacterium gram positive or gram negative? 

Gram positive 

8

What is the best diagnostic test for Mycobacterium?

Acid fast stain

Acid fast positive- they resist discoloration 

You'll be able to see macrophages packed with mycobacterium 

A image thumb
9

What other organism is a good differential for Mycobacterium?

Systemic fungi 

10

Mycobacterium can be either ______ or ______ pathogens

obligate or opportunistic

11

What diseases are caused by mycobacterium?

Tuberculosis- most common

Paratuberculosis (Johne's disease)- important in ruminants

Granulomatose disease 

12

What lipid virulence factors does mycobacterium have that aids in intra macrophage survival?

Lipids, glycolipids, and peptidoglyolipids 

13

Mycobacterium posses enzymes such as alkyl hydroperoxidase reductase that down regulates what?

the respiratory burst and the immune response in general 

14

Glycolipid attribuites to the ____ factor

Cord

(bacteria form cords when grown in liquid medium) 

15

Mycobacterium also produces ____ for iron acquisition 

siderophores 

16

Animal tuberculosis is a ____ disease

Reportable 

17

True/False: You treat food animals for tuberculosis

FALSE- you DO NOT treat food animals for tuberculosis. You immediatly eliminate those animals 

18

What type of inflammation does tuberculosis cause?

granulomatose 

19

Mycobacterium tuberculosis is found in what species 

humans and primates 

20

Mycobacterium bovis is found in what species?

cattle, humans, primates

 

humans get this from contaminated milk 

(picture shows tuberculosis in cattle with caseous necrosis)

A image thumb
21

mycobaterium avium is found in what species?

birds 

 

 

22

Which subspecies of mycobacterium is the most common causitive agent of tuberculosis in poultry?

mycobacterium avium subspecies avium 

23

What 4 species are known to be reservoirs for mycobacterium bovis?

white tail deer in USA- most important to know

badger

brush tailed possum

cape buffalo

24

How is tuberculosis transmitted?

respiratory tract and ailmentary routes

(inhalation or ingestion)

25

_____ zoonosis is also possible with Mycobaterium tuberculosis

reversible 

humans can transfer the mycobacterium to the animals 

26

What is the process if the organism is inhaled?

the mycobacterium can be taken in by macrophages and will start replicating within them and eventually reach the regional lymph nodes.

If strong immune response is evoked- the bacterial will be arrested in the lymph nodes. Granulomatose inflammation encapsulates the bacteria and shedding will not occur. In time, when the host gets stressed, the foci can open and release the live mycobacterium 

If the immune response is weak- the mycobacterium will continue replicating in macrophages. Reaches other tissue, including mammary gland and can be released in milk. Bacteria released in feces and contaminates the environment

27

What type of vaccine do we need for mycobacteria?

cell mediated vaccine

We need to stimulate TH1

28

_____ can also release a lot of bacteria into the environment

Coughing

29

What is a tubercle?

central area of calcification 

mycobacterium are associated with granulomatose lesions

30

If you are dealing with an immunosuppresed animal, that does not induce a cell mediated immune response, what kind of inflammation will occur?

Tuberculous pneumonia will occur and predominatly neutrophils will respond

Larger chance of rapid death and dissemination of the bacteria 

31

In a cell mediated immunity, what kind of cells with dominate?

macrophages- can protect from dissemination 

HOWEVER, can also aid in dissemination because tissue damage facilitates bacterial spread

32

What are some disease patterns of animal tuberculosis?

emaciation

enlarged lymph nodes

cough

diarrhea 

33

What should be high on your differentials if you have a cow with nasty lesions in the spleen, liver lungs, and lymph nodes with caseous necrosis?

mycobacterium bovis 

main agent causing tuberculosis in ruminants

(picture shows bovine tuberculosis)

A image thumb
34

What other types of mycobacterium have also been isolated in cattle other than mycobacterium bovis?

Mycobacterium avium- abortions

 mycobacterium tuberculosis 

35

If you do an acid fast stain and it is bovine tuberulosis positive, what should you see?

granulomatose inflammatory cells with acid fast organisms 

36

True/False Horses are commonly infected with mycobacterium

False: horses are rarely infected

 

37

What mycobacterium are swine normally infected by?

Mycobacterium bovis

usually via the ailmentary route 

38

what is the causitive agent for tuberculosis in swine and humans?

Mycobacterium avium subspecies hominissuis 

39

What is the most common mycobacterium of dogs and cats?

Mycobacterium bovis 

(dogs may also be infected with Mycobacterium tuberuclosis)

40

What disease does mycobacterium cause in dogs?

Marie's disease 

 

41

What mycobacterium are humans usually associated with?

Mycobacterium tuberculosis and mycobacterium bovis 

 

A image thumb
42

What are the routes of transmission to humans?

Mycobacterium tuberculosis- airborne (ex. homeless shelters)

Mycobacterium bovis- ingestion of contaminated milk

43

What are the most common areas of lesions for mycobacteria?

liver, spleen, and lungs 

These tissues are rich with macrophages, which is where mycobacteria can accumlate 

44

Pathogenesis of mycobacterium in Birds

disseminate to liver and spleen - wide nodules are spread throughout the tissues 

A image thumb
45

Tuberuolosis has high _____ in confined groups 

communicability 

46

What type of cattle are more resistant to tuberculosis and what type has a higher prevalence?

Zebu cattle- more reistant

dairy cattle- higher prevalence 

47

Tuberculosis is more associated with the ______ immune response 

cell mediated 

(without it the disease is more likely to disseminate)

48

Vaccines (BCG) for tubercuolsis is focused on ______

infants 

49

What can you use to disinfect a sample and isolate mycobacterium?

hypochlorite 

50

True/False: Tubercle bacilli are very hardy

True

survive long periods in soil

resistant to many disinfectants 

51

Laboratory diagnosis: Is it better to grow mycobacterium on media or do a molecular diagnosis?

molecular diagnosis

Grows very slow on media 

52

What is the most common test done to look for tuberculosis?

Tuberculin Test (hypersensitivty) 

Subcutaneous injection- fever

Conjuntival injection- conjunctivits

Intradermal route- local swelling 

53

What is the downfall of the Tuberculin test?

False positives and false negatives are frequent

 

54

What do positive tuberculosis skind test results look like?

Like this:

A image thumb
55

What is the treatment for mycobacterium?

identification and elmination of infected animals

 

56

True/False: eradication of bovine, human, and avian tuberculosis will dimish infection hazards for other species

TRUE 

57

What species is Johne's disease most important in?

ruminants 

(Guernsey, Jersey, and Shorthorn)

58

What is the causative agent of Johnes disease?

mycobacterium avium subspecies paratuberculosis 

59

What does Johne's disease cause?

wasting disease of ruminants

lesions in the GI tract. Does not allow absorption of nutrients which leads to loss of liquids 

REPORTABLE 

60

Who is the reservoir for Mycobacterium avium subspecies paratuberculosis?

symptomatic and asymptomatic wild and domestic ruminants, swine and rabbits 

spread mainly through ingestion or contact with feces

61

Pathogenesis of Johne's disease

1. bacteria are ingested and uptaken by MALT and M cells in GI tract

2. 12 month incuabtion period- slow growing

3. Form tuberculoid lesions with granulomas

4. Th1 lymphocyte recruitment

5. if IFN gamma is compromisd there will be dissemination (possible for IFN gamma to maintain the bacteria in the tuberculin stage so it won't disseminate)

6. granulomatous reaction

7. damage to the mucosl eptthelium (lepromatous stage)

62

What percent of John'es diseae progress to clinical diseases?

5% 

malabsorption, protein loosing entropathy 

63

What does Johnes disease cause in ruminants?

weight loss, diarrhea, enlarged lymph nodes 

 

64

What age group is most susceptible to Johne's disease?

young 

disease is mostly due to stress factors 

65

Is a vaccine used for Johne's disease in the US?

no, because the vaccine interfere with the diagnosis (false positives)

66

Best way to diagnose Johnes disease 

sample of ileocecal area

Ziehl neelsen stain- acid fast (positive rods)

67

What needs to be added to the media for Johnes disease to grow?

mycobactin- siderophore

68

_____ test are of high value because there are high antibody titers 

serological 

69

Johnes disease causes a _____ type hypersensitivity 

delayed 

70

Treatment for Johnes disease

eliminate infected animals 

overall cleanliness techniques 

71

______of milk is extremely important 

pasteurization 

72

Causative agent of Feline Leprosy 

Mycobacterium lepraemurium 

73

How is feline leprosy transmitted? 

rodent bite

74

Feline leprosy causes mycobacterial infection of the ____ and is acid fast _____

skin 

acid fast positive 

75

Feline leprosy treatment

surgical excision of affected sites 

76

True/False: Mycobacterium can also be present in reptilians, fish and amphibians associated with chronic type inflammation

True 

77

True/False: all mycobacterium have a zoonotic risk

True 

78

Which mycobacteria are found in aquatic organisms?

M. marinum

M. fortuitum

M. chelonae

79

Most common inflammation caused by mycobacterium 

granuloma inflammation packed with acid fast positive bacilli 

80

what is the zoonotic significance of the aquatic mycobacteria?

Fish handlers diease aka swimming pool granuloma