Brainscape's Knowledge GenomeTM

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


See full index

Microbio > Bacterial infections of the blood > Flashcards

Bacterial infections of the blood Flashcards

1
Q

What is bacteremia?

A

Bacterial infection of the blood

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

True or false: bacteremia is not uncommon, and can occur from trauma to a body site that has normal flora

A

True

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

What type of bacteremia results from dental extraction?

A

Transient–goes away quickly

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

What type of bacteremia results from pneumococcal pneumonia?

A

Intermittent

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

What type of bacteremia results from gram negative sepsis? What is the consequence of this?

A

Intermittent, but constantly there

Need to take multiple cultures to “catch” the bacteria

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

What type of bacteremia results from an intraabdominal abscess?

A

Intermittent, with disappearing amounts

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

What type of bacteremia results from infective endocarditis?

A

Continuous and low

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

What type of bacteremia results from catheter bacteremia?

A

Continuous

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

What are the three possible consequences of bactermia?

A
  1. Transient and benign
  2. Sepsis/shock
  3. Endocarditis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is sepsis?

A

Systemic inflammatory response syndrome (SIRS) that has a proven or suspected microbial etiology

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

Is bacteremia required for sepsis?

A

No–microbial could release toxins into the blood

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

What are the signs that occur with SIRS/sepsis? How many of these signs are needed to make a diagnosis of sepsis?

A

Fever/hypothermia
Tachypnea
Tachycardia
Abnormal WBC

Need to have at least two of these

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

What is severe sepsis?

A

Sepsis with one more more signs of organ dysfunction

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

What is septic shock?

A

Severe sepsis + hypotension (systolic pressure <90 mmHg)

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

What is refractory septic shock?

A

Septic shock that lasts for >1 h and does not respond to fluid and pharmacological treatment

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

What is multiorgan failure?

A

Dysfunction of >1 organ, as well as disseminated intravascular coagulation

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

What are the inflammatory cytokines that result in sepsis?

A

IL-6
TNF-alpha
DIC

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

What causes the organ failure in sepsis?

A

DIC

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

What general type of microorganism is usually responsible for sepsis (viruses, bacteria, fungi, or parasites)?

A

Bacteria

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

True or false: bacteremia is required to have bacterial sepsis?

A

False–exotoxins can cause sepsis

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

What is the pathophysiology behind sepsis?

A

Gram Negative LPS (or other PAMPs) causes release of cytokines

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

How can gram positive bacteria cause septic shock?

A

Release of exotoxins or peptidoglycan

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

How do fungi cause sepsis?

A

PAMPs associated with yeast like teichoic acid

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

LPS binds to what?

A

CD14 and TLR4

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

Which major cytokines does TLR4 recruit that causes sepsis?

A

TNF-alpha
IL-1
IL-6

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

What is the gram stain, morphology of staph Aureus? Catalase?

A

Gram positive cocci in clusters

Catalase positive

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

What is TSST-1?

A

Superantigen from Staph. Aureus

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

Toxic shock syndrome is caused by what now?

A

Wound infections

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

How does strep pyogenes Toxic shock syndrome compare to staph toxic shock syndrome?

A

Most patients are bacteremic with strep, unlike staph Aureus intoxications

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

Most patients who develop strep toxic shock syndrome have what? What species of strep causes this?

A

Necrotizing fasciitis

Strep Pyogenes (GAS)

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

What are the pyrogenic exotoxins? What are the types that strep pyogenes has?

A

Superantigens that are produced by strep pyogenes (A, B, and C)

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

How do you diagnose sepsis?

A

Symptoms + Blood cultures

33
Q

What percent of blood cultures in pts with septic shock will be positive?

A

40-70%

34
Q

What happens to the sensitivity of cultures when you take many?

A

Increases

35
Q

In pts that are on abx therapy, are cultures still useful?

A

no

36
Q

What is the treatment for hypotension seen in sepsis? Hypoxia?

A

IVF

Ventilatory therapy

37
Q

What is the treatment for DIC seen in sepsis? (2)

A

Transfusion, heparain

38
Q

What is the treatment for sepsis of unknown etiology?

A

Vancomycin/gentamicin

39
Q

Which two bacteria present with erythroderma (in sepsis)?

A

Step pyogenes or staph aureus

40
Q

What are the presenting symptoms with neisseria meningitidis (for sepsis)?

A

Sepsis + petechiae in skin

41
Q

What are the presenting symptoms with rickettsia rickettsii?

A

Petechial skin lesions

h/o tick bite

42
Q

What are the presenting symptoms with vibrio vulnificus?

A

Hemorrhagic skin lesions who has recently eaten raw oysters

43
Q

What is the endocardium?

A

The innermost layer of the tissues that lines the chambers of the heart

44
Q

Most endocarditis infections occur where within the heart?

A

On cardiac heart valves

45
Q

What are the symptoms of acute endocarditis? What is the usual pathogen?

A

Acute onset of high fever

usually Staph Aureus

46
Q

What are the symptoms of subacute endocarditis? What is the usual pathogen that causes this?

A

Nonspecific but weight loss, and night sweats

Usually associated with viridans strep

47
Q

What are the four clinical features of endocarditis?

A
  1. New or unchanging heart murmur
  2. Splenomegaly
  3. Skin lesions
  4. Retinal lesions
48
Q

What are Roth spots?

A

Retinal hemorrhages that can be caused by endocarditis

49
Q

What are splinter hemorrhages?

A

Red linear streaks in the nail bed. Can be caused by endocarditis

50
Q

What are janeway lesions? Painful?

A

Painless lesions on palms or soles of the feet

51
Q

What are the Osler nodes? Painful?

A

Painful, subcutaneous nodule sin the pads of the digits

52
Q

What are the two most common etiological agents of endocarditis?

A
  1. Viridans strep

2. Staph Aureus

53
Q

What percent of endocarditis cases are caused by enterococci?

A

5-18%

54
Q

What percent of endocarditis cases are caused by fungi?

A

2-4%

55
Q

What is the gram stain and morphology of strep? Catalase result?

A

Gram positive cocci in chains. Aerobic

Catalase negative

56
Q

What is GAS?

A

Strep pyogenes

57
Q

What is GBS?

A

Strap agalactiae

58
Q

What is GDS?

A

Enterococcus

59
Q

What are the three strep groups that are not labeled in the lancefield groups?

A

Strep viridans group:
Strep pneumonia
Strep mutans
Strep mitis

60
Q

S mitans and S salovarius can cause what serious disease?

A

Endocarditis

61
Q

What are the hemolytic results of the viridans strep?

A

Alpha

62
Q

True or false: viridans strep are normal flora

A

True

63
Q

What is the treatment for infections with viridans strep?

A

PCN or vanco if resistant

64
Q

How does the virulence compare for strep compared to staph

A

Less

65
Q

How can you tell difference between strep viridans from strep pneumonia (since both are Alpha-hemolytic)?

A

Optochin test

Pneumonia is susceptible

66
Q

What are the two risk factors required for endocarditis?

A
  1. Susceptible cardiovascular substrate (prosthetic heart valve)
  2. Source of bacteremia
67
Q

Why are IV drug users susceptible to endocarditis?

A

Constant exposure to bacteria

68
Q

What is the average age of onset for endocarditis?

A

70 years

69
Q

What is the common nosocomial cause of bacterial endocarditis?

A

Central catheter placement

70
Q

What is the pathophysiology of endocarditis?

A

Vegetations on the heart valves where there are cardiac abnormalities

71
Q

How does splenomegaly occur with endocarditis?

A

Septic emboli

72
Q

What are the two major criteria for diagnosing endocarditis?

A
  1. Positive blood culture with a typical organism

2. Evidence of endocardial involvement (echo)

73
Q

What are some of the minor criteria for endocarditis?

A
  1. Fever
  2. Predisposition
  3. Vascular phenomenon
74
Q

What is the treatment for endocarditis?

A

Prolonged, aggressive IV abx

75
Q

What is the MOA of superantigens?

A

Stimulate T cells by binding to MHC II in the V-beta region of the T cell receptor

76
Q

Endocarditis with acute onset is likely caused by what pathogen?

A

Staph Aureus

77
Q

Endocarditis with subacute onset is likely caused by what pathogen?

A

Viridans strep

78
Q

What are the two general genera of bacteria that are the usual suspects for endocarditis?

A

Strep (enterococci too) or staph

79
Q

What causes the DIC seen in sepsis?

A

Impairment of the protein C pathway of coagulation

Microbio (50 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions