Endocarditis

Question 1

There are 3 layers of the heart wall, describe each

Answer 1

1. EPICARDIUM = Outer Layer, Visceral Pericardium
2. MYOCARDIUM = Middle Layer, Makes up majority of the heart mass
3. ENDOCARDIUM = Inner Layer, Lines the chambers, valves, & vessels

Question 2

how does IE occur?

Answer 2

when bacteria enters the bloodstream and lodges onto a heart valve, esp those with prior damage or turbulent blood flow

Question 3

what is a common contributor to the etiology of IE? examples?

Answer 3

oral source
Dental extraction, periodontal surgery, tooth brushing, chewing candy

Question 4

other causes of bacteremia besides the main one?

Answer 4

IV drug use, EGD, colonoscopy, TURP, IV catheters

Question 5

The localization of infection is partly determined by ?

Answer 5

the production of turbulent blood flow

Question 6

what type of IE is MC, when is it not?

Answer 6

Left-sided IE is more common, except among IVDU

Question 7

MC pathogen to cause native valve endocarditis

Answer 7

Staph aureus; Streptococcus is next

Question 8

Valve/Heart disorders that increase risk for IE:

Answer 8

1. Rheumatic valvular disease
2. Congenital heart disease – PDA, VSD, tetralogy of Fallot
3. MVP with MR
4. Degenerative heart disease, AS due to bicuspid AV, Marfan syndrome

Question 9

Common causes/types of endocarditis

Answer 9

1. Prosthetic Valve Endocarditis
2. IV Drug User Endocarditis
3. Native Valve Endocarditis
4. Nosocomial/Healthcare-associated Endocarditis
5. Fungal Endocarditis

Question 10

MC pathogenetic cause of Prosthetic Valve Endocarditis

Answer 10

1. Staphylococci (coagulase-negative and coagulase-positive) - early (within 2 months)
2. Streptococci - Late (>2months)

Question 11

MC pathogenetic cause of IV Drug User Endocarditis? where is the infection MC?

Answer 11

1. Staph aureus is the MC causative organism
2. Streptococci (viridans) and enterococci are next most frequent
3. Tricuspid valve

Question 12

leading causes of Nosocomial/Healthcare-associated Endocarditis

Answer 12

Central and peripheral IV catheters, pacemakers and ICDs, HD shunts, and permacaths

Question 13

MC pathogenetic cause of nosocomial/healthcare-associated endocarditis

Answer 13

G+ cocci - S. aureus, enterococci, nonenterococcal streptococci

Question 14

what type of endocarditis is More commonly found in IVDU and ICU patients who receive broad-spectrum abx

Answer 14

Fungal Endocarditis

Question 15

complications with endocarditis

Answer 15

1. Rupture of valve tissue or chordal structures, leading to valvular regurgitation
2. Vegetation may obstruct the valve orifice or create a large embolus
3. Conduction system affected by myocardial abscess
4. Infection may invade the interventricular septum, causing intramyocardial abscesses or septal rupture
5. Septic systemic and pulmonary emboli

Question 16

MCC of death in pts with IE

Answer 16

Heart Failure

Question 17

Presentation of IE

Answer 17

1. within 2 wks - 6 months
2. sx of systemic infection, emboli, or other complications (CHF)
3. MC fever (90%), chills, weakness, shortness of breath, night sweats, loss of appetite and weight loss
4. MSK sx, such as back pain, are common
5. heart murmurs (80%)
6. CHF is present in up to 2/3 of cases
7. Septic emboli
   - Pulmonary emboli
   - Systemic emboli

Question 18

However, what pt population with TV endocarditis have murmur only 1/3 of the time

Answer 18

IVDU

Question 18

pleuritic chest pain, cough with blood-tinged sputum, and cavitating lesions on chest x-ray
what could be the cause?

Answer 18

Pulmonary emboli

Question 19

Systemic emboli OF IE to what arteries

Answer 19

renal, cerebral, coronary and mesenteric arteries

Question 20

Physical findings of peripheral manifestations in IE caused by vasculitis/emboli:

Answer 20

1. Petechiae (red, non blanching lesions in crops on conjunctiva, buccal mucosa, palate, extremities) - vasculitis or emboli
2. Splinter hemorrhages (linear, red-brown streaks in nail beds) - vasculitis or emboli
3. Janeway lesions - PAINLESS patches on palms/ soles
   Emboli; Staph
4. Osler nodes - PAINFUL nodules on pads of fingers/toes
   Vasculitis; Strep
5. Roth spots - Oval, pale lesions surrounded by hemorrhage
   Vasculitis; Strep

Question 21

petechiae seen in IE is MC caused by what pathogen

Answer 21

Strep and staph common causes

Question 22

Splinter hemorrhages is MC caused by what pathogen

Answer 22

Strep and staph common causes

Question 23

erythematous/hemorrhagic macular or nodular, painless patches on palms or soles
what is this?
MC pathogen?

Answer 23

Janeway lesions
Staph

Question 24

painful nodules on pads of fingers or toes) caused by vasculitis what is this? MC pathogen?

Answer 24

Osler nodes strep

Question 25

oval, pale retinal lesions surrounded by hemorrhage caused by vasculitis in IE what is this

Answer 25

Roth spots

Question 26

one of the most serious complications of IE

Answer 26

CNS embolization

Question 27

what must be in DDx in young pt with CVA? s/s?

Answer 27

IE HA or develop seizures, possibly due to toxic encephalopathy, meningoencephalitis

Question 28

diagnostic testing for IE

Answer 28

1. _START WITH_: **CBC, blood cx** 2. Nonspecific labs are possible - Anemia - obtain CBC - inflammation - elevated erythrocyte-sedimentation rate, CRP, LDH, lactic Acid (these are very non specific markers for inflammation) - UA - proteinuria and hematuria 3. Bacteremia - Blood cx should be obtained prior to initiation of antibiotics - At least 3 sets of blood cx obtained from different venipuncture sites, with the first and last samples drawn at least 1 hour apart - May be negative, due to previous antibiotics, or fastidious organisms, such as Legionella, Bartonella, Chlamydia or fungi

Question 29

collect 3 sets of what type of blood cx?

Answer 29

1. aerobic bacteria 2. anaerobic bacteria 3. fungi

Question 30

what diagnostic testing is recommended in all cases of suspected IE? which is most sensitive?

Answer 30

1. echo - TTE may be sufficient - TEE is more sensitive, especially for small vegetations, in patients with large body habitus

Question 31

diagnostic criteria used for IE

Answer 31

Duke Criteria 1. Major criteria - Positive blood culture for IE - Typical organisms, 2 or more positive cultures - Evidence of endocardial involvement on echo intracardiac mass on a valve or supporting structure - myocardial abscess; partial dehiscence of a prosthetic valve - New regurgitant murmur 2. Minor criteria - Predisposing heart condition or IVDU - Fever (>38 C or >100.4 F) - Vascular and embolic phenomena - including major arterial emboli, septic pulmonary infarcts, mycotic aneurysm, intracranial hemorrhage, conjunctival hemorrhage, or Janeway lesions - Immunologic phenomena - glomerulonephritis, Osler nodes, Roth spots, and rheumatoid factor - Microbiologic evidence - Single positive blood culture or serologic evidence of active infection with typical organism

Question 32

diagnostic criteria interpretation of duke diagnosis

Answer 32

1. Definitive IE - 2 major criteria, or 1 major and 3 minor, or 5 minor 2. Possible IE - 1 major and 1 minor, or 3 minor

Question 33

overall management for IE

Answer 33

1. Management of patients with IE involves multiple aspects - Antibiotic therapy (Involve ID for this) - Management of CHF - Management of systemic/pulmonary sequelae - Surgery - dental eval

Question 34

abx tx for IE (all types)

Answer 34

1. Antibiotic therapy - 4 to 6 weeks - Native valve IE - Pen G and gentamicin, vancomycin (MRSA) - IVDU - Nafcillin, gentamicin, vancomycin - Prosthetic valve IE - Vancomycin, gentamicin, and rifampin - Fungal IE - Amphotericin B (not curative), surgery (definitive tx) Subsequent antibiotic choice is based on blood or pathology culture results

Question 35

surgery management for IE usually involves what 3 things?

Answer 35

1. Involves open sternotomy valve replacement, repair or debridement - Timing and necessity is individualized for each patient (only ~25% undergo surgery) - Prosthetic valve IE rarely occurs after valve replacement for IE, so delaying surgery to prolong antibiotic therapy is never appropriate if patient remains hemodynamically unstable or fulfills one of the following criteria

Question 36

7 indications for surgery in IE

Answer 36

1. **CHF refractory to standard medical therapy (MC indication)** 2. Fungal IE 3. Persistent sepsis after 72 hrs of abx 4. Recurrent septic emboli, esp after 2 weeks of abx 5. Ruptured aneurysm of the sinus of Valsalva 6. Conduction disturbances caused by septal abscess 7. Kissing infection of anterior mitral leaflet with IE of AV

Question 37

what eval should be thoroughly evaluated to identify and eliminate oral disease for IE

Answer 37

dental eval should focus on periodontal inflammation and pocketing around teeth and caries that may result in infection and subsequent abscess A full series of intraoral radiographs should occur when the patient is stable

Question 38

Maintaining ____ is just as effective as abx for Endocarditis Prophylaxis

Answer 38

good oral hygiene only 10% of IE cases can be prevented by the administration of preprocedure antibiotics

Question 39

the most common source of spontaneous bacteremias in IE (oral health)

Answer 39

Gingivitis

Question 40

Antibiotic prophylaxis is reserved for who?

Answer 40

1. high risk for IE and only for those procedures that have higher likelihood of bacteremia risks: - Prosthetic heart valves - Prior endocarditis - Cyanotic congenital heart disease (unrepaired, repaired, or partially repaired) - Cardiac transplantation recipients who developed cardiac valvulopathy

Question 41

Endocarditis Prophylaxis Procedures

Answer 41

1. Dental procedures - Any procedure involving manipulation of gingival tissue or the periapical region of teeth, or perforation of the oral mucosa 2. Respiratory tract procedures - Tonsillectomy or adenoidectomy - Other invasive procedures involving incision of the respiratory mucosa 3. Procedures on infected skin or musculoskeletal tissue including I&D of an abscess No longer recommended for GI or GU procedures

Question 42

abx regimen for Endocarditis Prophylaxis

Answer 42

1. Amoxicillin 2. If allergic to penicillin: - Clindamycin 600 mg PO - Cephalexin 2 grams PO - Azithromycin or clarithromycin 500 mg PO 3. If unable to take PO: - Ampicillin 2 grams IM or IV - If allergic to penicillin: Cefazolin or ceftriaxone 1 gram IM or IV, or clindamycin 600 mg IV