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Flashcards in Exam 1 - Endocarditis Deck (67)
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1
Q

What is Infective Endocarditis?

A

Severe infection invading endothelium of heart

2
Q

What and where is the endothelium of the heart?

A

Membrane lining the chambers of the heart and covers cusps of heart valves

3
Q

Which valves does endocarditis infect?

A

All valves in the heart

4
Q

Which valve has the worst prognosis of outcome if infected?

A

Aortic valves

5
Q

What is the presentation of Infective Endocarditis?

A

Might have low-grade fever, fatigue, heart murmur, and petechiae but might not. Can be non-specific.

6
Q

What is involved in the diagnosis of Infective Endocarditis?

A

Signs, symptoms, cultures, and echo. Cultures are most important.

7
Q

Which heart valve is the least commonly involved with IE?

A

Pulmonic

8
Q

What two conditions can affect the Mitral/Bicuspid Valve causing IE?

A
  1. Rheumatic Heart Disease

2. Calcified lesions in elderly

9
Q

Which valve is involved in IV drug users?

A

Tricuspid valve

10
Q

What are two major risk factors for developing IE?

A
  1. Prosthetic Valve

2. Previous endocarditis

11
Q

What is the best lab test to use for diagnosing IE?

A

Blood cultures. Get 3 sets within 24 hours, and one set before any abx administered.

12
Q

Which echocardiogram is best for IE?

A

Transesophogeal. Regular transthoracic might not show anything.

13
Q

Arterial embolization (septic emboli) occurs in when which valve in colonized?

A

Aortic valve. Nasty clumps of bacteria thrown at other organs.

14
Q

What is the mortality range for IE?

A

20-50%

15
Q

What are the three most common organisms in Infective Endocarditis?

A
  1. Staphylococcus
  2. Streptococcus
  3. Enterococcus
    All are Gram +.
16
Q

How does Subacute/Non-Virulent IE present in contrast to Acute/Virulent IE?

A

Subacute/Non-Virulent=Low grade fever, malaise, fatigue, weight loss, murmur (Strep Virdans)

Acute/Virulent=High grade fever, chills/sweats, sepsis, murmur (S. Aureus)

17
Q

What are the two types of acute and the associated virulence with Infective Endocarditis?

A

Subacute=Non-virulent organisms (Strep Virdans)

Acute=Virulent organisms (S. Aureus)

18
Q

Which organism causes Subacute/Low-virulent IE?

A

Virdans steptococcus (VSG)

19
Q

Which organism causes Acute/Virulent IE?

A

S. Aureus

20
Q

What is the predominant pathogen for IE?

A

S Aureus

21
Q

What are two risk factors that can cause S Aureus IE?

A
  1. Post cardiac surgery

2. IV Drug User

22
Q

What are two major risk factors of IE caused by Virdians streptococcus?

A
  1. Normal flora

2. Dental procedures

23
Q

What are two populations who develop IE caused by Enterococcus faecalis?

A
  1. Elderly men with prostatitis
  2. Women with GU infections
    Caused from Indigenous fecal and perineal flora
24
Q

Elderly men with prostatitis and women with GU infections are like to get IE caused by which organism?

A

Enterococcus faecalis

25
Q

How do you select the right antibiotic to use for IE?

A

Dependent on cultures and sensitivity. Resistance is on the rise.

26
Q

What is the Inoculum Effect?

A

When high bacterial concentration renders antimicrobial activity less effective

27
Q

In the Inoculum Effect the higher the bacterial concentration the ____ effective the antibiotics

A

Less effective

28
Q

What is the most important approach in treating IE?

A

Isolation of infecting pathogen and determining susceptibilities

29
Q

What level of dose and duration of antibiotics are used for IE?

A

High-dose, long duration of bactericidal antibiotics

30
Q

What is the benefit of using a combination antibiotics for treatment of IE? What can it help prevent?

A

Synergism, when the two working together provide better treatment then alone. Helps prevent resistance.

31
Q

List 4 situations where combo antibiotic therapy should be used? (Hint: Includes one organism)

A
  1. Infection of unknown origin
  2. Shorter duration for uncomplicated IE (2 weeks)
  3. Enterococcal endocarditis (Ampicillin + Gentamicin)
  4. Prosthetic valve (Rifampin)
32
Q

WhIch antibiotics to use for S Aureus IE? Which to use if resistant?

A

Initial: Nafcillin or Oxacillin if susceptible.
PCN allerg/tolerate prob: Cefazolin
MRSA: Vancomycin if resistant to Oxacillin.
VRSA: Daptomycin if resistant to Vancomycin.

33
Q

If PT is on Vancomycin and they stop producing urine or SrCr elevates showing kidney injury?

A

Hold Vancomycin and possibly switch to Daptomycin.

34
Q

What are initial treatments for Enterococcus Faecialis if kidney is good?

A
  1. Preferred: Ampicillin/Penicillin G + Gentamicin

2. Ampicillin + Gentamicin

35
Q

What us initial combo treatment for Enterococcus Faecialis if kidney is no good or gentamacin resistant?

A

Kidney no good=Ampicillin + Ceftriaxone

Gent Resist=Amp/PenG + Streptomycin or Amp + Ceftriaxone

36
Q

Treatments for Enterococcus if resistant to Gentamicin?

A
  1. Ampicillin + Ceftriaxone

2. Ampicillin or PenG + Strepomycin

37
Q

Enterococcus resistant to PCN or unable to tolerate Beta-lactam?

A

Vancomycin + Gentamycin

38
Q

Treatment for Enterococcus Faecialis if resistant to everything including Vancomycin?

A

Daptomycin or Linezolid

39
Q

What is initial treatment for IE from PCN-susceptible Viridins Group Strep? What can be added-on if normal renal function?

A

Penicillin G

Normal renal function: Gentamicin for 2 weeks

40
Q

What is most likely the cause of IE from dental issues? Which organism most common?

A

Poor oral hygiene or dental procedure.

VGS most common as part of normal mouth and respiratory flora.

41
Q

What two prior issues require someone to have prophylaxis before a dental procedure?

A
  1. Prosthetic heart valve

2. Prior endocarditis

42
Q

What antibiotic is the standard oral regiment for prophylaxis against IE from dental issues? What if allergy to PCN?

A

Standard=Single dose Amoxicillin PO 1h prior to procedure

PCN Allergy: Clarithromycin or Azithromycin. High dose Cephalexin.

43
Q

What is treatment for VGS if poor kidney function (CrCl less than 50mL/min)?

A

Longer duration of Ceftriaxone and hold Genatmicin

44
Q

What is treatment for IE from Viridins Group Strep if rash from PCN? Anaphylaxis?

A

Rash=Ceftriaxone + Gentamicin

Anaphylaxis=Vancomycin

45
Q

What is mechanism of intravenous Penicillins and Celpahosporins and which organism does it not cover?

A

Binds to Penicillin Binding Proteins to inhibit cell wall synthesis. No MRSA coverage.

46
Q

Which bacterial infection can PT get from being in intravenous PCN?

A

C. Diff

47
Q

What is cross-reactivity of PCN and Cephalosporins? How does generation fit into that?

A

7-10%. Later generation PCN the less cross-reactivity.

48
Q

Which 4 organisms are Vancomycin used and when?

A

MSSA, MRSA, some entero, streptococcus. When there is actual resistance.

49
Q

Emperic dosing and interval of Vancomycin is based on what two criteria?

A
  1. Actual body weight

2. CrCl

50
Q

What is Red Man Syndrome? Treatment?

A

From Vancomycin. Treat by slowing down infusion.

51
Q

What should trough concentration be for Vancomycin? After which dose do you check?

A

15-20, before fourth dose

52
Q

If SrCr increases with Vancomycin or urine output decreases what do you do?

A

FREAK OUT!

consider lower dose or change to daptomycin

53
Q

What is mechanism for Daptomycin and when is it used?

A

Induces cell membrane dysfunction resulting in death. Used for skin/soft tissue infx, bacteremia, endocarditis.

54
Q

What two diseases/body places can you not used Daptomycin?

A
  1. CNS for meningitis

2. Lungs for pneumonia

55
Q

What is MOA of intravenous Gentamicin and what it does to bacteria?

A

Aminoglycoside. Disrupts 30S subunit. Bactericidal based on concentration.

56
Q

What is the post-antibiotic effect of Gentamycin and what does it allow?

A

Larger dose=longer effect. Allows for once-daily dosing.

57
Q

What does Gentamycin have synergy with?

A

Beta-lactam antibiotics

58
Q

What is the standard interval and extended interval for Gentamycin? How is Gentamycin dosed?

A

Standard=every 8h
Extended=1/day

Dosed on Ideal Body Weight.

59
Q

Gentamycin is preferred for _____ but not recommended for ___/___ NVE.

A

Preferred for VGS non-complicated IE.

Not recommended for MRSA/MSSA NVE.

60
Q

What is Gentamycin’s effect on hearing and kidneys?

A

May be ototoxic by concentrating in hair cells.

Nephrotoxic with pre-existing kidney damage. Don’t use if CrCl less than 50ml/min.

61
Q

Linezolid is used in what two forms?

A

PO or IV

62
Q

Linezolid static against ____ and ____; Cidal against _____

A

Static: S. Aureus and enterococci
Cidal: streptococcus

63
Q

Linezolid approved against

A

enterococcus resistant to PCN, AG, and vanco

64
Q

Intravenous Rifampin used against ____ caused by which organism?

A

PVE caused by staphylcocci

65
Q

Rifampin is a strong inducer. What does this mean for meds like Wayfarin?

A

Increases metabolism of drugs which decreases their concentrations. Ex: Wayfarin concentration reduced with Rifampin so INR not as high as needed thus need to increase Wayfarin dose. Becareful when discontinuing Rifampin and other drugs.

66
Q

What two things must be monitored with long-term amino glycosides?

A
  1. Renal function

2. Otic disorders, get serial audiographs

67
Q

C. Diff can occur ___ weeks after last dose of abx for IE

A

4 weeks