Infective endocarditis

Question 1

Pathophysiology of IE

Answer 1

• Damaged valves (prosthetic mainly)
• Fibrin and platelets will deposit
• on top of that organisms will deposit forming vegetations
• These vegetations are loosely attached which embolize
• can lead to strokes, infarctions, abscess

Question 2

IE

Define IE

Answer 2

it’s an endovascular infection of cardiovascular structures. such as cardiac valves, endocardium, large intrathoracic vessels, intrathoracic foreign bodies such as prosthetic valves, pacemakers

Question 3

IE

IE is more prone on

Answer 3

damaged heart valves

Question 4

IE

The two factors which contributes to the development of IE

Answer 4

• Presence of organisms in blood stream
• abnormal cardiac endothelium facilitating their adherence and growth

Question 5

IE

Reasons for bacteremia

Answer 5

• poor dental hygiene
• IV drug use
• Soft tissue infection - cellulitis, abscess
• therapeutic procedures- dental treatment
• IV cannulae/ venous access
• cardiac surgery/ pacemakers
• dialysis via central or femoral line

Question 6

IE

commonly affected valves

Answer 6

• AV
• MV

Question 7

IE

Prosthetic valve endocarditis

Answer 7

• Early- hospital acquired organisms
• Late- community acquired

Question 8

IE

Hospital acquired MOs causing PVE

Answer 8

Staph aureus. During the first 60 days after valve replacement

Question 9

IE

Community acquired PVE

Answer 9

Strep viridans. occurs after 60 days from the valve replacement

Question 10

IE

New PVE

Answer 10

• Early- upto 12 months
• Late- after 12 months

Question 11

IE

Which PVE is more common nowadays

Answer 11

hospital- acquired PVE

Question 12

IE

common MOs in the mouth

Answer 12

• alpha hemolytic strep viridans
• dental procedures

Question 13

IE

MOs in prolonged indwelling vascular catheters

Answer 13

• Staph aureus
• TPN pts, IVDU,Pts on long standing ABx

Question 14

IE

Gut and perineum MOs

Answer 14

• Enterococci
• prolonged hospitalizations, underlying GUT or GIT disease

Question 15

IE

Bowel malignancy MO

Answer 15

Strep bovis (rare)

Question 16

IE

Native and prosthetic valve endocarditis MOs

Answer 16

Staph aureus
Strep viridans
Staph epidermidis

Question 17

IE

Soft tissue infection MO

Answer 17

Staph. (iv drug users, diabetes)

Question 18

IE

Rare MOs causing IE

Answer 18

HACEK
* Haemophilus
* Actinobacillus
* Cardiobacter
* Eikenella
* Kingella

Question 19

IE

Culture (-) ve

Answer 19

• Coxiella burnetti
• Chlamydia
• HACEK
• Bartonella

Question 20

IE

Clinical features

Answer 20

• PUO
• Malaise
• Clubbing
• CVS- murmurs, HF
• Arthralgia, Pyrexia
• Skin lesions- oslers nodes, splinter hemorrhages, janeway lesions, petechiae
• Eyes- roth spots, conjunctival splinter hemorrhages
• Mild splenomegaly
• Neurological- cerebral emboli, mycotic aneurysm
• Renal- hematuria, glomerulonephritis

Question 21

IE

DDs of PUO

Answer 21

• TB
• Lymphoma
• HIV
• SLE
• Hepatoma
• RCC

Question 22

IE

Clubbing due to cardiac issues DDs

Answer 22

• Atrial myxoma
• Cynaotic HD
• IE

Question 23

IE

Osler’s nodes

Answer 23

paniful nodes on the pulp of fingers

Question 24

IE

Glomerulonephritis UFR

Answer 24

• Protein +
• RBC +

Question 25

# IE DDs for a mild splenomegaly

Answer 25

* Typhoid * IE

Question 26

# IE L/sided endocarditis sends emboli to

Answer 26

systemic circulation ( Brain abscess, splenic abscess)

Question 27

# IE R/ sided endocarditis sends emboli to

Answer 27

pulmonary circulation ( multiple lung abscess)

Question 28

# IE Ix

Answer 28

* Blood cultures * serological tests * FBC * BU, SE * LFT * ESR, CRP * Urine * ECG * CXR * Echo

Question 29

# IE Blood cultures

Answer 29

3 sets of cultures from 3 different sites

Question 30

# IE FBC findings

Answer 30

* Normochromic normocytic anemia * PMN leukocytosis * thrombocytopenia/ thrombocytosis

Question 31

# IE LFT

Answer 31

ALP elevated

Question 32

# IE ESR, CRP

Answer 32

both elevated

Question 33

# IE Urine tests

Answer 33

proteinuria, hematuria

Question 34

# IE ECG

Answer 34

evidence of MI, conduction defects

Question 35

# IE CXR

Answer 35

evidence of HF R/S endo- multiple pulmonary emboli

Question 36

# IE echo

Answer 36

transesoph > transthoracic

Question 37

# IE Complications

Answer 37

* Heart failure due to valvular lesions * AV block- brady arrythmias * Anemia- microscopic hematuria

Question 38

# IE Heart blocks occur due to

Answer 38

aortic root abscess

Question 39

# IE Why is giving PO ABx useless in IE

Answer 39

coz valves are relatively avascular. so giving PO ABx won't penetrate

Question 40

# IE Mx

Answer 40

high dose empirical ABx- benzyl penicillin + gentamicin (4-6 weeks)

Question 41

# IE ADRS of gentamicin

Answer 41

* ototoxicity * nephrotoxicity

Question 42

# IE Whats done while the pt is on ABx

Answer 42

adequate hydration, assess renal function regularly and ask the pt about any tinnitus

Question 43

# IE ABx for suspected staph endo (IVDU, recent Hx of cardiac surgery)

Answer 43

Vancomycin Gentamicin

Question 44

# IE ABx for clinical endo, culture results awaited, no suspicion of staph

Answer 44

penicillin gentamicin

Question 45

# IE ABx for strep endo

Answer 45

Penicillin Gentamicin

Question 46

# IE ABx for enterococcal endo

Answer 46

Amoxicillin Gentamicin

Question 47

# IE ABx for staph endo

Answer 47

* vancomycin * Flucloxacillin * Benzylpenicillin * Gentamicin

Question 48

# IE Indications for surgery

Answer 48

* severe HF due to valvular damage * Failure of ABx Rx * Large vegetations w evidence of systemic emboli * Abscess/ heart block formation in heart

Question 49

# IE Continued fever in a pt w IE

Answer 49

* Incorrect ABx * Inadequate dose * Complications- abscess * Recurrent embolization * Large vegetation * Unrelated to IE

Question 50

# IE Reason for continued fever in IE with large vegetation

Answer 50

ABx can't penetrate

Question 51

# IE What to look for in continued fever in a pt w IE

Answer 51

* cannula- site infection ( touch cannula site and see if its warm, red, swollen) * UTI- catheter * Dengue fever

Question 52

# IE for how long can you keep a cannula

Answer 52

for 3 days

Question 53

# IE For IE Mx

Answer 53

we usually put a central line

Question 54

# IE Prevention

Answer 54

* Good dental hygiene * ABx prophylaxis

Question 55

# IE ABx prophylaxis is given

Answer 55

**indicated cardiac conditions** * Unrepaired cyanotic HD * Prosthetic valves, valve repair * past IE **Indicated procedures** * Dental procedures involving gingival tissue * Respi procedures breaching mucosa * Procedures on infected skin/ soft tissue * GIT, GUT procedures on infected system

Question 56

# IE ABx prophylaxis

Answer 56

* Amxoicillin 2g, 1h prior to procedure * Clindamycin 600mg or azithromycin 500mg if allergic to penicillin