Chapter 156: Endocarditis

Question 1

TRUE or FALSE: Pediatric endocarditis is common

Answer 1

FALSE: uncommon
causes: post op CHD, structural HD, RHD, catheter - related bacteremia

Question 2

most commonly affected site of endocarditis

Answer 2

Mitral valve

ATP
2nd: aortic
3rd: tricuspid - INJECTION DRUG USE
4th: pulmonic

Question 3

Healthcare-associated endocarditis

Answer 3

• > 72 hours after admission without evidence of endocarditis on admission
• develops within 6 months after hospital discharge
• develops within 6 months of cardiovascular manipulations

Question 4

other term for non bacterial thrombotic vegetations

Answer 4

marantic endocarditis

from: hypercoagulable states, malignancy, or systemic lupus erythematosus (Libman-Sacks endocarditis)

Question 5

single most common cause of infective endocarditis

Answer 5

Staphylococcus is the single most common cause

followed by: streptococci

Question 6

TRUE or FALSE: Streptococcal endocarditis is linked to increased risk of in-hospital death

Answer 6

FALSE: streptococcal endocarditis tends to be indolent

*staphylococcal endocarditis - increased risk of in-hospital death
*Enterococcal endocarditis - associated with underlying valvular disease and risk factors (DM, manipulation of the GU and lower GI)

Question 7

culture negative cases without prior antibiotic administration is most often due to?

Answer 7

fastidious organisms (usually from the HACEK group—Haemophilus, Aggregatibacter, Cardiobacterium, Eikenella, and Kingella—and also Bartonella and Coxiella burnetii)

*Polymerase chain reaction techniques aid pathogen detection

Question 8

common presenting symptoms of endocarditis

Answer 8

• fever (80% - both signs and fever)
• chills
• weakness
• dyspnea

Question 9

most common complications of IE

Answer 9

• CHF (44%)

*CNS findings (30%)
*peripheral embolization (22%)

Question 10

most common CNS complication

Answer 10

embolic stroke involving the middle cerebral artery

Question 11

Cutaneous findings of small, tender subcutaneous nodules on the pads of the digits

Answer 11

Osler nodes

*Cutaneous signs are not specific and occur in other types of vasculitis or bacteremia

Question 12

Cutaneous findings of small hemorrhagic painless plaques on the digits

Answer 12

Janeway lesions

*Cutaneous signs are not specific and occur in other types of vasculitis or bacteremia

Question 13

most common laboratory finding in IE

Answer 13

elevation of ESR (erythrocyte sedimentation rate)

Question 14

ECG findings suggestive of spread of infection into the conduction system

Answer 14

Prolonged PR interval, new left bundle branch block, or new right bundle branch block with left anterior hemiblock

Question 15

ECG findings suggestive of extension of infection from the mitral annulus into the atrioventricular node or proximal bundle of His

Answer 15

Junctional tachycardia, Wenckebach block, or complete heart block

Question 16

Intra-aortic balloon counterpulsation aids the emergency management of unstable mitral valve rupture but is contraindicated for?

Answer 16

aortic valve rupture

Question 17

to reduce the risk of hemorrhagic transformation for native valve endocarditis after CNS embolic event it should be managed by?

Answer 17

withholding anticoagulation for at least 2 weeks

*if with prosthetic valves being treated with anticoagulants - maintain as long as no evidence of bleeding

*Prosthetic valve + embolic stroke: anticoagulants and anti-platelet should be withheld at least 2 weeks to reduce the risk of hemorrhagic transformation

Question 18

Empiric treatment of suspected endocarditis of native valves

Answer 18

penicillinase-resistant penicillin, a cephalosporin, or daptomycin

*GENTAMICIN no longer recommended
*ADD Vancomycin for patients with complications

Question 19

Empiric treatment of suspected prosthetic valve endocarditis

Answer 19

antistaphylococcal ß-lactam agent or vancomycin adding gentamicin and rifampin

Question 20

Highest-Risk Conditions for Endocarditis

Answer 20

• Prosthetic heart valves
• Prosthetic material used for valve repair
• History of previous infective endocarditis
• Unrepaired cyanotic congenital heart disease
• Repaired congenital heart defect with prosthetic material or device
• Repaired congenital heart disease with residual defects
• Cardiac transplant recipients with valve regurgitation due to a structurally abnormal valve

NOTE: GIVE ANTIBIOTIC PROPHYLAXIS PRIOR TO DENTAL PROCEDURES

Question 21

Risk factors for repeat episode of Endocarditis

Answer 21

• IV drug use
• Hemodialysis

Question 22

Empiric Therapy of Suspected Bacterial Endocarditis

Answer 22

Uncomplicated history: Ceftriaxone, 1–2 grams IV, Nafcillin, 2 grams IV, Oxacillin, 2 grams IV, Cefepime, 1 gram IV and Vancomycin, 15 milligrams/kg, or Tobramycin, 1 milligram/kg IV

Injection drug use, HA, MRSA, on oral antibiotics: Nafcillin 2 grams IV plus Vancomycin 15 mg/kg IV OR Daptomycin 8–10 milligrams/kg IV

Vancomycin resistant Enterococcus: Daptomycin 8–10 milligrams/kg or Linezolid 600 milligrams

Prosthetic heart valve: Nafcillin 2 grams IV (if oxacillin-susceptible) or Vancomycin, 15 milligrams/kg IV (if oxacillin resistance is suspected) PLUS Gentamicin, 1–2 milligrams/kg IV PLUS Rifampin, 300 milligrams PO

Question 23

Modified Duke Criteria for IE

Answer 23

Definitive: pathologic criteria
Clinical criteria: 2 major OR 1 major 3 minor OR 5 minor
Possible criteria: 1 major 1 minor OR 3 minor
Rejected: does not meet criteria, resolution with antibiotic therapy for4 days or less, no pathologic evidence