Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Microbiology > Bacteriology Exam 4 (GPR) > Flashcards

Bacteriology Exam 4 (GPR) Flashcards

1
Q

Actinomycetes: definition and gram stain

A

Actinomycetes is an order of bacteria that is: NONMOTILE, BRANCHING, and FILAMENTOUS. It is a GPR.

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

Main genera of interest in Actinomycetes

A

Nocardia spp

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

Nocardia catalase

A

Catalase +

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

Nocardia (gram, catalase, oxygen requirements)

A

gram positive rods, catalase positive, strictly aerobic

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

Epidemiology of Nocardia spp.

A

Soil and water organisms (NOT normal flora)

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

Where does Nocardia abscessus cause disease? Nocardia brasiliensis?

A

N. abscessus can cause disease in any body source, N. brasiliensis causes diseases in skin/tissue only.

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

Who are at the greatest risk for Nocardia infections?

A

Immunosuppressed patients

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

What does could an acinomycete gram stain look like that causes speculation of Nocardia infection?

A

Gram-positive branching or partially branching beaded filaments

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

What kind of stain can help us to identify Nocardia spp and differentiate them from mycobacteria?

A

Acid fast stain to observe presence of yellow to orange granules

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

What are special selective media to grow Nocardia in vitro? Why do we use them?

A

We can use BCYE with antibiotics to grow Nocardia. Nocardia are non-fastidious and can grow on routine media, but they are VERY slow growing which is why we can use the selective media to speed up the growth process.

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

What is the most isolated human pathogen in Nocardia sp?

A

N. asteroides

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

Nocardia (+ or -): Acid fast, Lysozyme resistance, Urea hydrolysis, Nitrate reduction, growth anaerobically

A

+ acid fast, + lysozyme resistance, + urea hydrolysis, +/- nitrate reduction, - growth anaerobically

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

Lysozyme broth growth with Nocardia

A

Nocardia is resistant to Lysozyme so it will grow in Lysozyme broth and it will be more turbid looking.

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

E. rhusiopathiae epidemiology

A

Zoonotic bacteria associated with animal workers (fish handlers, farmers, slaughterhouse workers, food prep workers, vets)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Types of infections caused by E. rhusiopathiae (3 types)

A
  1. skin lesions (erysipeloid)
  2. diffuse cutaneous infection with systemic symptoms
  3. bacteremia and endocarditis (severe!)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

E. rhusiopathiae: Erysipeloid infection

A

localized skin infection resulting in sharply defined, purplish-red zone lesions on hands/fingers

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

Arcanobacterium epidemiology

A

Normal inhabitant of the mucosal membranes of sheep/dogs/cats/pigs (ZOONOTIC). Can cause infections in immunocompromised patients.

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

Gardnerella vaginalis epidemiology

A

Endogenous flora of the vagina that are opportunistic pathogens and kept in check by Lactobacillus sp.

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

Lactobacillus sp. epidemiology

A

Normal flora of human vagina to keep proper acidic pH, beneficial to the human host but may cause serious infections in immunocompromised patients

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

Primary purpose of Lactobacillus in vaginal areas

A

Metabolizes glucose to lactic acid to produce acidic vaginal pH environment to inhibit growth of pathogenic bacteria

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

Gram stain appearance of Arcanobacterium

A

delicate, curved, gram-positive rods with pointed ends

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

Lactobacillus gram stain appearance

A

pleomorphic GPR occurring in LONG chains and in coccobacilli and spiral forms

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

Ways to diagnose BV (bacterial vaginosis)

A
  1. Wet mount prepared in saline reveals “clue cells” which are squamous epithelial cells with numerous attached small rods
  2. Clue cells are present with lactobacilli being absent or very few in number
  3. Perform Nugent Scoring of BV grams
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What will Gardnerella spp. not grow in? Why?

A

Blood culture broths - Gardnerella spp. are inhibited by SPS

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

What is a distinguishable characteristic of E. rhusiopathiae?

A

One of the few GPR that has the ability to produce H2S.

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

How to ID Arcanobacterium vs. Trueperella spp.

A

A. haemolyticum is beta hemolytic. Truperella sp. is non-hemolytic. (except Trueperella pyogenes)
A. haemolyticum is negative for liquefaction of gelatin, T. pyogenes is positive

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

Trueperella pyogenes

A

Formerly Arcanobacterium; animal pathogen; rare cause of infections

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

Which organism will create a REVERSE CAMP positive reaction on BAP?

A

A. haemolyticum

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

Colony morphology for E. rhusiopathiae

A

Two colonies exist: large and rough, or smooth and small
*Both may start as gamma hemolytic but become alpha hemolytic after prolonged incubation

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

E. rhusiopathiae: catalase, motility, gram stain, H2S, VP, urease, and esculin hydrolyze

A

Catase -
Nonmotile
pleomorphic GPR
H2S +
VP -
Urease -
Esculin hydrolyze -

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

E. rhusiopathie gram stain appearance

A

GPR that can form long filaments and arranged in V shape (can appear gram variable)

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

Colony morphology/hemolysis of Lactobacillus sp.

A

Multiple colony morphologies:
1. pinpoint alpha hemolytic
2. rough, gray colonies with alpha/gamma hemolysis

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

What 3 pathogenic bacteria does Lactobacillus suppress?

A

Gardnerella vaginalis, Mobiluncus spp., and Prevotella spp.

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

Lactobacillus infections

A

Only found in immunocompromised patients, can cause possible endocarditis (rare)

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

G. vaginalis hemolysis patterns on BAP vs. HBT agar

A

On BAP, G. vaginalis is nonhemolytic
On HBT agar, G. vaginalis is beta hemolytic

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

Nugent Scoring of BV grams: what does a normal score indicate?

A

High numbers of Lactobacillus (no BV)

37
Q

Nugent Scoring Criteria

A

Score of 7 or more indicates BV (no lactobacillus, high pathogens)
Score of 4-6 is intermediate
Score of 0-3 is normal (normal or high amounts of lactobacillus)

38
Q

Affirm VP

A

Tests vaginal specimens for Gardnerella, Trichomonas, and Candida (blue indicates positive presence)

39
Q

Many lactobacillus spp. are highly resistant to ________.

A

Vancomycin

40
Q

Arcanobacterium: What may it cross react with? How to troubleshoot this?

A

Arcanobacterium is beta hemolytic and can cross react with Group G beta hemolytic Strep: THIS is why it is always important to perform a gram stain. (Group G beta hemolytic step will be GPC, Arcanobacterium is GPR)

41
Q

Listeria monocytogenes epidemiology

A

Environmental opportunistic pathogen to humans through direct contact with animals, soil, and vegetation
*Primary transmission most often due to ingestion of contaminated foods (meats, veggies, dairy)

42
Q

Listeria monocytogenes - who does it most often infect?

A

immunocompromised and neonates due to vertical transmission from mother to fetus

43
Q

Listeria monocytogenes virulence and pathogenicity

A

Listeriolysin O - reduce T cell responsiveness
Phospholipases - enable escape from phagosome
Act A - induces hot cell actin polymerization

44
Q

Corynebacterium diphtheriae epidemiology

A

Not normal flora - transmission through direct person to person contact via respiratory droplets, exudative pus from skin lesions, or fomites

45
Q

What is C. diphtheriae virulence due to?

A

potent cytotoxic exotoxin from a plasmid (tox gene)

46
Q

S&S of diphtheria

A

pharyngitis, difficulty swallowing, fever
cell necrosis and exudate forms a tough gray-to-white pseudomembrane that attaches to tissue

47
Q

Non-toxigenic C. diphtheriae

A

Causes cutaneous diphtheria that is characterized by nonhealing ulcers and membrane formation (does not have the plasmid tox gene)

48
Q

What are most C. jeikeium infections associated with? Why?

A

HAI’s - colonizer of inguinal, axillary, and rectal areas of body (associated with catheters, shunts, medical devices)

49
Q

C. ulcerans epidemiology and infections

A

Normal microbiota in humans and cattle; zoonotic infections that usually present as skin infections or pneumonia

50
Q

C. pseudotuberculosis epidemiology and infections

A

normal microbiota of various animals such as sheep, goats, horses (zoonotic) infections in humans is rare but may cause suppurative granulomatous lymphadenitis (lungs)

51
Q

C. pseudodiphtheriticum epidemiology and infections

A

Normal microbiota of human upper respiratory tract and skin flora
Opportunistic pathogen that gain access to sterile sites and may cause sepsis, endocarditis, pneumonia, and lung abscesses

52
Q

C. stratium epidemiology/infections

A

normal microbiota of skin, considered to be nosocomial/HAI due to catheterization - may cause bacteremia, pneumonia, lung abscesses, osteomyelitis, meningitis

53
Q

C. urealyticum epidemiology/infection

A

Normal skin flora, big problem for HAIs
Most infections are related to UTIs, wound infections

54
Q

C. diphtheria: catalase, motility, urease

A

Catalase +
Nonmotile
Urease -

55
Q

C. jeikeium: catalase, oxygen requirements, urease, nitrate reduction, hemolysis

A

Catalase +
Urease -
Nitrate reduction -
Gamma hemolytic

56
Q

C. pseudodiphtheriticum: nitrate reduction and urease

A

nitrate reduction +
urease +

57
Q

C. pseudotuberculosis: urease

A

Urease +

58
Q

C. ulcerans: nitrate, urease

A

nitrate -
urease +

59
Q

C. urealyticum: nitrate, catalase, urease

A

nitrate -
catalase +
RAPID urease +

60
Q

What will enhance the growth of C. urealyticum?

A

lipid-containing medium (lipophilic organism)

61
Q

How can you decipher C. diphtheria from other Corynebacterium? What will a positive C. diphtheria look like?

A

Cystine-tellurite blood agar and Modified Tinsdale agar
Presumptive positive for C. diphtheriae occurs when there is a brown-black halo produced on both media.

62
Q

What Corynebacterium will have a REVERSE camp reaction?

A

C. pseudotuberculosis and C. ulcerans

63
Q

What Corynebacterium is RAPIDLY urease positive?

A

C. urealyticum

64
Q

L. monocytogenes media to grow

A

VERY fastidious - needs lots of things to grow. BHI is most common nonselective media used for cultivation of Listera sp.

65
Q

Listeria monocytogenes: hemolysis, catalase, motility, bile esculin, CAMP

A

beta hemolytic
catalase positive
motile at room temp (umbrella motility)
bile esculin +
CAMP + (block/small arrowhead)

66
Q

Organism with block/rectangular CAMP positive result

A

L. monocytogenes

67
Q

What does L. monocytogenes usually cause?

A

meningitis in neonates/immunocompromised

68
Q

Organism that is motile at room temp

A

L. monocytogenes
“tumbling end over end” on wet mount
“umbrella motility” on agar tube

69
Q

What GPR is easily identified based on its salmon-colored colonies on BAP?

A

Rhodococcus equi

70
Q

What is the Elek Plate Testing used for? What is a positive result?

A

It is used to differentiate C. diphtheriae toxin-producing strains vs. non-toxin producing strains.
The presence of precipitin lines = strain produced the toxins.

71
Q

What is the lipophilic Corynebacterium?

A

C. jeikeium

72
Q

C. diphtheriae: CAMP test

A

CAMP negative

73
Q

B. anthracis: motility, hemolysis, morphology on BAP, gram stain

A

non-motile, gamma hemolytic, “medusa head”/”comet tail” morphology, large rectangular bacilli with centrally located spores

74
Q

Epidemiology of B. anthracis

A

Common soil and environmental organism - may be recovered in skin, blood, CSF, or respiratory samples

75
Q

When are endospores produced?

A

During harsh environmental conditions to enhance bacterial survival

76
Q

B. anthracis virulence and pathogenicity

A

Lethal toxin - kills the cells
Edema toxin - swelling and inflammation of tissue
protective antigen - carrier protein to facilitate LT/ET cellular entry

77
Q

Cutaneous B. anthracis

A

Most common infection type - endospores inoculate areas of broken skin.
2-3 days after exposure: small papule appears at site of inoculation
3-7 after exposure: black eschar appears

78
Q

Gastrointestinal B. anthracis infection

A

Ingestion of endospores leads to lesions on mouth area, results in N/V/D, vomiting blood

79
Q

B. anthracis inhalation (what is another name for it, S&S, mortality rates, what do chest x ray reveal)

A

Called wool sorter’s/rag pickers disease - from breathing in endospores. S&S include 2-5 days of non-productive cough, N/V, respiratory distress, shock, death
Highest mortality rates
Chest x ray reveals pleural effusion and mediastinal widening

80
Q

B. cereus epidemiology and common illnesses

A

soil/environmental organism that can cause food poisoning with ingestion of contaminated meats/veggies/rice/grains/dairy

81
Q

Heat Shock Testing

A

Used for growth and enhancement of endospore producing bacteria
- Sample heated 60-70C for 30 minutes to kill vegetative cells but keep endospores alive to increase recovery

82
Q

All labs must report _______ to the CDC with __ days.

A

B. anthracis; 7 days

83
Q

> 1 um with no endospore swelling within the cell

A

vegetative B. anthracis, cereus, thuringiensis

84
Q

<1 um with no endospore swelling

A

B. subtilis

85
Q

How to distinguish B. anthracis from other bacillus spp.

A

B. anthracis is gamma hemolytic and non-motile
Other bacillus sp. are beta hemolytic and motile

86
Q

B. anthracis: motility, catalase, colony morphology/hemolysis

A

non motile
catalase +
large gray and flat with medusa head and gamma hemolytic

87
Q

B. cereus: motility, hemolysis, gram stain

A

beta hemolytic, motile, frosted glass appearing bacilli on gram stain

88
Q

B. cereus: what does it cause? what 2 types?

A

Food poisoning
Diarrheal: 8-16 hour incubation period with longer duration
Emetic: 1-5 hour incubation period with shorter duration

89
Q

How to identify B. subtilis from other beta hemolytic and motile bacillus sp.

A

<1 um cell width

Microbiology (24 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions