Miscellaneous GNB-Coccobacilli Exam 3 Flashcards Preview

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Flashcards in Miscellaneous GNB-Coccobacilli Exam 3 Deck (62)
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1
Q

Vibrio general info.

A

Oxidase pos. Gram neg bacilli. Ferments glucose. MAC pos. Non-lactose fermenter except for V. vulnificus. Facultative anaerobes. likes h20 environment. NOT apart of normal flora.

2
Q

Aeromonas general info

A

Oxidase pos. Gram neg bacilli. Ferments glucose. MAC pos. Non-lactose fermenter except for V. vulnificus. Facultative anaerobes. likes h20 environment. NOT apart of normal flora. Produces deoxyribonuclease.

3
Q

Chromobacterium general info.

A

Oxidase pos. Gram neg bacilli. Ferments glucose. MAC pos. Non-lactose fermenter except for V. vulnificus. Facultative anaerobes. likes h20 environment. NOT apart of normal flora.

4
Q

What is the specimen for vibrio, aeromonas ,and chromobacterium?

A

Stool or rectal swabs (stool needs to be transported in Cary-Blair medium when vibrio is suspected.

5
Q

What is the selected media for Vibrio spp?

A

Thiosulfate citrate bile salts sucrose (TCBS). Bile salts inhibit gram pos organisms and high ph (8.6) inhibits other intestinal flora.

6
Q

Presumptive ID for Vibrio?

A

Medium to large, smooth, opaque colonies with greenish hue on SBAP.

7
Q

Presumptive ID for Aeromonas?

A

Large, round, raised, and opaque.

8
Q

Chromobacterium- Presumptive ID?

A

round, smooth, convex, black to dark purple with almond like smell on SBAP.

9
Q

Should oxidase testing be done on MAC plate?

A

No. Fermentation of lactose can create acids that can acidify the medium and if falls below pH of 5.1 can get false negatives.

10
Q

What organism is the cause of cholera?

A

Vibrio cholerae

11
Q

How is cholera mostly transmitted?

A

Through contaminated seafood ( waters exposed to feces)

12
Q

What vibrio serotypes have been involved in epidemics/pandemics?

A

01 and 0139

13
Q

What virulence factors does Vibrio cholerae have?

A

Cholera toxin (CT), hemolysins, cytotoxins, and pili.

14
Q

What does cholera lead to?

A

dramatic fluid loss (dehydration), hypotension-damage to kidneys, and death can occur. Rice water stools Blood is absent in stool.

15
Q

What is the treatment for cholera?

A

Two vaccines OUTSIDE US. Antibiotics decrease severity (Tetracycline and doxycycline). Rehydration is vital.

16
Q

What kind of specimens are for Vibrio vulnificus?

A

Wounds, blood, or stool (from ingestion of seafood) oysters Doesn’t spread from person to person.

17
Q

How do you treat Vibrio vulnificus?

A

Amputation of infected limbs perhaps. Toxins released include lipases, proteases, and collagenases. *Doxycycline plus ceftazidime recommended.

18
Q

Signs of Vibrio parahemolyticus?

A

watery diarrhea, cramping, nausea, vomiting, fever w/in 24 hours. Self-limiting to 3 days. All cases of Vibrio spp. must be reported to state health depts.

19
Q

What is the treatment for Vibrio parahaemolyticus?

A

Hydration. Usually no antibiotics (tetracycline in severe cases)

20
Q

What organism can cause gastroenteritis with diarrhea most commonly in children?

A

Aeromonas spp. (Aeromonas hydrophilia)

21
Q

What can Aeromonas spp. cause?

A

HUS with kidney failure

22
Q

What organism starts as cellulitis and then progresses to lymphadenitis to systemic infection possible with visceral abscess formation and shock?

A

Chromobacterium violaceum

23
Q

What is the treatment for Chromobacterium violaceum?

A

No set guidelines. Pencillin activity is variable. Cefotaxime is effective

24
Q

Media for Bartonella?

A

Fresh chocolate NO BAP and MAC

25
Q

Media for Streptobacillus moniliformis?

A

Sheep in increased CO2 and humidity.

26
Q

Media for Helicobacter?

A

Chocolate or Brucella agar

27
Q

Campylobacter media?

A

CAMPY-BAP, CAMPY CVA, and CCDA (modified charcoal cefoperazone deoxycholate agar

28
Q

Media for Brucella?

A

Brucella agar (adds heated horse serum)

29
Q

Media for Francisella tularensis?

A

Media with cysteine (buffered charcoal yeast extract agar)

30
Q

What causes Tularemia (disease with a fever of 104 degrees C)?

A

Francisella tularensis

31
Q

B. Quintana and B. henselae most commonly associated with ….

A

Human disease

32
Q

Trench fever

A

B. Quintana (now reemerging as bactermia, endocarditis, lymphadenopathy)

33
Q

Cat scratch fever, bacteremia, enlarged lymph nodes and pustule at sight of infection from cat infection with fleas harboring the organism?

A

B. henselae

34
Q

Specimen for Bartonella spp?

A

Blood (lysed) and tissues

35
Q

Incubation for Bartonella spp?

A

Prolonged (2 weeks) with CO2 and high humidity

36
Q

Rat bite fever? From what organism?

A

Lymphadenitis, rash, flu-like symptoms, relapsing fever, chills. Systemic illness (arthritis, meningitis, liver, spleen, etc.) Streptobacillus monoiliformis

37
Q

Haverhill fever? From what organism?

A

ingesting contaminated milk rather than a rat bite (more pronounced GI symptoms). Streptobacillus moniliformis.

38
Q

What is the specimen of choice H. pylori?

A

Biopsy specimens

39
Q

H. pylori-urease test?

A

Positive

40
Q

What can H. pylori cause?

A

Chronic gastritis, peptic ulcer disease, gastric carcinoma.

41
Q

How can H. pylori survive in the stomach?

A

They secrete urease that produces ammonia and CO2 so it acts like a buffer for the HCL. Also secretes proteases and phospholipases that break down glycoproteins in mucus. destroying 1st line of defense (ulcers)

42
Q

Which organisms prefer micro aerobic (5-10% O2) environments?

A

Campylobacter and Acrobacter

43
Q

These organisms have animal reservoirs (pigs, poultry, sheep, bulls)

A

Campylobacter and Acrobacter

44
Q

This genera is the most common bacterial agent of gastroenteritis in the US

A

Campylobacter (2nd-Salmonella; Norovirus most common cause of acute gastroenteritis)

45
Q

Presumptive ID-Campylobacter?

A

Gray to pink to yellow gray colonies. Mucoid.

46
Q

Treatment for Campylobacter?

A

Erythromycin *usually self-limiting and don’t require antibiotics.

47
Q

3 Major pathologies from Campylobacter?

A

Febrile systemic disease, periodontal disease, and gastroenteritis.

48
Q

What is associated with neonatal meningitis or compromised adults?

A

Chryseobacterium

49
Q

Definitive ID-Chryseobacterium?

A

MAC pos. Oxidase pos. glucose oxidizer.

50
Q

What organism is normal flora of dogs and cats?

A

Bordetella bonchiseptica

51
Q

Definitive ID-Alcaligenes and Bordetella (nonpertussis)

A

MAC pos. oxidase pos. non-glucose utilizers.

52
Q

What organisms are capnophiles?

A

Actinobacillus, Aggregatibacter, Kingella, Cardiobacterium, and Capnocytophaga
**all ferment glucose, MAC neg, Oxidase pos.

53
Q

What are the organisms of HACEK?

A

Aggregatibacter aprophilus, Aggregatibacter actinomycetemcomitans, cardiobacterium hominis, Eikenella corrodens, Kingella spp.

54
Q

HACEK is found most common where?

A

Normal flora in oral cavity, upper respiratory, and genitourinary tracts.

55
Q

Where is Cardiobacterium hominis isolated from?

A

Blood cultures only

56
Q

Definitive ID -Eikenella corrodens

A

MAC neg, Oxidase pos. pits of the agar where colonies are located. bleach like odor.

57
Q

What is Eikenella corrodens associated with?

A

Human bite wounds or closed fist wounds (facial punches with abrasions)

58
Q

Media for K. denitrificans?

A

Thayer Martin* N. gonnorrhoeae also on media so have to differentiate with ID. K is catalase neg superoxol neg and nitrate pos.

59
Q

Summary-MAC pos. Oxidase neg.

A

Enterobacteriacae, Acinetobacter, Chryseomonas, Flavimonas, Stenotrophomonas.

60
Q

MAC-pos. Oxidase pos.

A

Pseudomonas, burkholderia, achromobacter, chryseobacterium, alcaligenes, bordetella (nonpertussis), vibrio, aeromonas, plesiomonas shigelloides, chromobacterium violaceum

61
Q

MAC-neg. Oxidase-pos.

A

Sphingomonas, Moraxella and elongated Neisseria, Eikenella corrodens, Pasterella, Actinobacillus, Kingella, Cardiobacterium.

62
Q

MAC-neg. Oxidase-variable.

A

Haemophilus