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Flashcards in Upper GI micro Deck (72)
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1
Q

What is it meant by normal flora?

A

part of the microbiome - the ecological community of commensal, symbiotic, and pathogenic microorganisms that literally share our body space.

2
Q

Where are Peyer’s patches found? What are they?

A

small masses of lymphatic tissue found throughout the ileum region of the small intestine.

3
Q

What are the 4 phyla in the stomach?

A

Proteobacteria, Firmicutes, Actinobacteria and Bacteroidetes

4
Q

Wgat are some things in the normal flora of the large intestine

A
Microbe rich, “microbiome” studied here
Anaerobes
Gram-negative rods
Enterococcus – can survive wide range of stressors and enviromental conditions
Spirochetes
5
Q

Define caries?

A

Infectious disease that causes tooth decay

Pain, tooth loss, spread of infection

6
Q

what are the risk factors of developing caries

A

high-sugar diet, poor oral hygiene, reduced amount of saliva, smoking, periodontal disease

7
Q

Who has the highest prelvance of caries?

A

children, common worldwild, at least 1 carried filled

8
Q

What causes demineralization?

A

fementable sugars + acid producing bacteria

9
Q

What is Periodontal Disease?

A

infectious disease destroying supporting structures of teeth- tissues and bone, -(common and mild form gingivitis- just the gums)

10
Q

How common is gingivitis?

A

Affects more than 30% of population worldwide

11
Q

Peridontisis is more severe than gingivitis- what else is peridontitis asscoaited with?

A

Heart attack
Stroke
Lung disease
Premature birth or having a baby with low birth weight, in women

12
Q

What is a biofilm made up of?

A

consist of two or more species of bacterial microcolonies that are enclosed in a glycocalyx(polysacchrides)

13
Q

What does a biofilm provide the bacteria?

A

Adherence
Protection from the immune system
Protection from antibiotics
Symbiotic (but also anti-symbiotic) relationships
Local conditions of pH, etc, in a normally inhospitable environment

14
Q

What microbes are dominate in the mouth?

A

Anaerobic organisms predominate but also have gram pos lactobacilli and spirochetes. Some bacteria assoacited with pathogenic infections are there but in lower amlounts considered commensals

15
Q

What groups of microbes play a role in protecting against dental caries and periodontitis

A

streptococci, they as producing hydrogen peroxide which inhibits the growth of other oral bacteria

S. sanguinis, S. oralis, S. gordonii, and S. mitis – the “mitis group”

16
Q

Microbes that cause caries are usually located in plaques on tooth surfaces, often in crevices or between teeth are usually gram pos/neg?

A

postive!

17
Q

Microbes that cause periodontal disease do their destruction primarily below the gumline – in the subgingival space are gram pos/neg

A

negative!

18
Q

The bad strep is hard to identify-why?

A

that many oral streptococci are naturally transformable and readily exchange DNA with one another- this complicates 16S rRNA analysis

19
Q

Strep mutans characterics?

A

gram pos, cocci beads on a string, cat neg, facultative anaerobe, alpha hemo, opotchin resistant

20
Q

Different bwtn virulence factors and toxins?

A

Toxins are virulence factors- which enable the microbe to establish itself within a host

21
Q

What are strep mutans virlence factors

A

adhesin-like surface-associated proteins (e.g. AgI/II family), extracellular glucosyltransferases (Gtfs)

22
Q

What are extracellular glucosyltransferases (Gtfs)

A

constituents of the pellicle and are capable of synthesizing glucans (a type of polysaccharide) in situ from sucrose. Glucans provide additional S. mutans binding sites, as it binds avidly and in large numbers to these polymers

23
Q

What are the “Keystone pathogens” in periodontal disease

A

Treponema denticola – a spirochete
Tannerella forsythia – anaerobic, gram negative
Porphyromonas gingivalis – best studied because it can be cultured
Aggregatibacter (formerly Actinobacillus) actinomycetemcomitans is related to the severity of the periodontal disease

24
Q

Porphyromonas gingivalis characteristics?

A

gram neg, bacillus, anerobic, assharolytic, black pigmented colonies on blood agar, bacitracin resistant

25
Q

Highlighted list of peridontal disease?

A

P. gingivalis, Capnocytophaga gingivalis, Prevotella denticola

26
Q

How can you prevent periodontal disease?

A

Less sugar in diet
Brush and floss frequently
Fluoride
Increased Saliva flow – sugar free gum

27
Q

What does fluoride do?

A

for remineralization to counteract the effects of demineralization under low pH conditions
Inhibits bacterial glycolysis and pH maintenance enzymes

28
Q

Is gingivitis reversible?

A

yes, treatment is the same as prevention

29
Q

What is mild periodontitis treatmetn?

A

scaling, root planing, antibiotics-topical, oral if goes to tissues, emperical-combo of amox/metronidazole

30
Q

what is severe periodontitis treatment?

A

surgical tx,

31
Q

What pathogen causes oral thrush

A

candida

32
Q

What pathogen causes Hairy leukoplakia

A

EBV

33
Q

Who gets hairy leukoplakia?

A

HIV patients

34
Q

What pathogens are assocaited with Ludwig’s angina

A

Bacterial: alpha-hemolytic streptococci, staphylococci and bacteroides groups

35
Q

Who gets ludwigs angina>

A

people who a severe tooth infection or peridontal disease

36
Q

What pathogens cause Diphtheria/

Strep throat

A

Corynebacterium diphtheriae

Streptococcus pyogenes

37
Q

What are the symptoms of ludwigs angina?

A
Breathing difficulty
Confusion or other mental changes
Fever
Neck pain
Neck swelling
Redness of the neck
Weakness, fatigue, excess tiredness
38
Q

What form of candidis is dangerous?

A

Esophageal form

39
Q

Tx candidis

A

Most commonly a topical treatment: clotrimazole troches and nystatin suspension (swish and swallow).
Unresponsive cases: a systemic antifungal such as fluconazole
Worst case: IV administration of amphotericin B (significant side effects)

40
Q

If candidias is untreated what can happen?

A

invasive candidiasis

41
Q

Where would C.diptheriae be found? Characterics?

A

gram pos, bacilli, non spore forming, non motile, PSEUDOMEMBRANE!

42
Q

S. pyogens characterics, where would it be found?

A

gram pos, cocci, catalase neg, b hemolytic, bacitracin senstive- on the tonsils!

43
Q

Characteristics of canidad albicans?

A

fungus, hyphael forms, bacilli, non-spore forming, non motile,

44
Q

Leukplakia not caused by a virus is thought to be caused by what?

A

smoking and chewing tobacco – or other irritations

45
Q

What are the characterics of EBV?

A

herpesviridae, ds, linear, DNA, enveloped

46
Q

Whats the difference bwtn thrush and leukoplakia?

A

leukoplakia cannot be wiped away!

47
Q

How is h.pylori transmitted?

A

fecal-oral

48
Q

What percent is infected with H. pylori?

A

US: 50% of adults are infected

Third world: virtually all adults infected

49
Q

Characteristics of H. pylori?

A

gram neg, flagellated helix shaped rod (spirilli), microaerophilic, catalase and oxidase POS, urease pos,

50
Q

t percent of those with H. pylori infection get ulcers? cancer?

A

only 10-20, 1-2% get distal gastric cancer

51
Q

Its possible that H. pylori disease outcomes may be related to what?

A

YOUR micrbiome!

52
Q

inflammation of gastric mucosa is called?

A

Gastritis

53
Q

What are the symptoms of gastritis

A

Gnawing or burning ache in upper abdomen. May become either worse or better with eating
Nausea
Vomiting
A feeling of fullness in your upper abdomen after eating

54
Q

What is a gastric ulcer?

A

Open sores that develop on the inside stomach lining.

55
Q

What are the more common symptoms of the gastric ulcer?

A

Felt anywhere from navel to breastbone
Worse when stomach is empty
Flare at night
Often temporarily relieved by eating foods that buffer stomach acid
Disappear and then return for a few days or weeks

56
Q

how does h. pylori evade the immune response ?

A

Inhibit phagocytic uptake
Inhibit adaptive immune response
Evade killing by reactive oxygen species and nitric oxide
Evade recognition by pattern recognition receptors

57
Q

H pylori is urease pos, what does that due to the local environment

A

raises pH- annomia

58
Q

How does h pylori get through the low PH layer?

A

flagella!

59
Q

What does the increase pH allow the bacteria to do?

A

Swim around!

60
Q

What are the two best virulence factors of H. pylori?

A

VacA and CagA

61
Q

What does VacA do?

A

Pore forming cytotoxin that allows leakage of Ca+ from epithelial cell

62
Q

What deos CagA do?

A

Type 4 secretion system (TFSS) is a needle through which CagA travels into the host cytosol and affects the proliferative activities, adhesion, and cytoskeletal organization of epithelial cells.

63
Q

How do you diagnosis H. pylori>

A

Endoscopy + culture
Breath Test
Stool test
Blood test

64
Q

Tx of H. pylori

A

Antibiotics will be necessary (often clarithromycin and amoxicillin; the 1,2) to remove H. pylori
Proton pump inhibitor (3rd arm of triple therapy) to aid in the healing of ulcer

65
Q

Whats the gold standard of diagnosing H. pylori?

A

endoscopy but its invasive and expenisve, instead use a use a guided biopsy

66
Q

How is the rapid urease test done>

A

With a biopsy, sample is put on a plate containing urea and phenol red, if H. pylori is present, it will hydrolize urea to ammonia and produce a red color. Yellow=neg

67
Q

What does the breath test detect?

A

radioactive Co2- the patient is given capsule with urea and if they have H.pylori will be converted to ammonia, Good for diagnosis
Good for confirming cure
Requires skilled technician

68
Q

What does the blood test H. pylori detect?

A

antibodies, Useful for initial diagnosis only

Not useful for confirming cure

69
Q

What is a stool antigen test good for regarding H pylori?

A

Easy
Good for diagnosis
Good for confirming cure

70
Q

What kind of cancer can H. pylori cause?

A

MALT and Gastric carcinoma

71
Q

What kind of cancer is MALT? symptoms? tx?

A

b cell, Indigestion, heartburn (stomach pain),antbiotics

72
Q

What kind of cancer is

Gastric carcinoma

A

Cancer of stomach lining (epithelial cells)