infective endocarditis Flashcards
(36 cards)
what is infective endocarditis?
infection of:
- heart valves
- endocardial lined structures eg pacemakers, septal defects or surgical patches
treatment of infective endocarditis
- antibodies/antimicrobials
- surgery to repair and remove infectious material
- then treat the complications which it has caused
name the different types of IE
- native valve IE (mitral or aortic) left sided - most common
- left sided prosthetic valve IE
- right sided IE - tricuspid or pulmonary
- device related IE
what is the most common type of IE
left-sided native valve IE
native valve IE and common organisms
- mitral or aortic
- natural heart valves
- caused by S. verdidans and S. aureas
left sided prosthetic valve IE
- infection of a prosthetic valve
- aortic / mitral
2 groups:
early = <1year of surgery
late = >1 year of surgery
right sided IE
- most common in IV drug users
- effects tricuspid more than pulmonary
device related IE
- infection of cardiac implantable devices
- can occur with/without concurrent valve IE
who is most commonly affected by IE?
- the elderly
- young IV drug users
- the young with congenital heart disease
- anyone with prosthetic heart valves
clinical presenttation
- depends on the site vand bacterial organism
- signs of systemic infection eg fever and sweats
- stroke, pulmonary embolus, bone infection, kidney dysfunction and MI - embolus
- valve dysfunction - heart failure and AF
name the major and minor points of Dukes criteria (2+5)
major:
- pathogen grown from blood cultures
- evidence of endocarditis on echo or valve regurgitation
minor:
- predisposing factors eg iv drug use
- fever above 38
- vascular phenomina eg janeway lesions
- immune phenomina eg roth spots
- equivival blood cultures
what criteria from the duke’s criteria are for a definite and possible diagnosis?
definite:
- 2 major / 1 major
- 3 minor / 5 minor
possible:
- 1 major, 1 minor / 3 minor
contrast the 2 types of echo
transthoracic echo:
- safe
- non-invasive
- no discomfort
- poor quality images - lower sensitivity
transoesophageal echo:
- excellent pictures
- more invase
- generally safe - risk of perforation or aspiration
peripheral stigmata
- classical signs of peripheral embolism from IE
Janeway lesions - painless red macules on palms and soles - embolism lodges in small arteries
oslers nodes - painful red/purple nodules on fingers and toes
splinters and haemorrhages - thin red / brown streaks under finger and toe nails
roth spots - retinal haemorrhage with pale centre
when may someone have a negative culture growth?
if they have had previous antimicrobial therapy
diagnostic tests
- transthoracic echo
- transoesophageal echo
- ECG - secondary complications
treatment
- empiric IV antibiotic until culture comes back
- antibiotics IV - 6 weeks
- treat complications
- surgery
when should you do surgery?
- if infection cannot be cured with antibiotics
- if complications arrive
- remove infected devices
- replace valve after infection cured
- to remove large vegetation before it embolises
who should receive prophylaxis?
only patients at high risk:
Prosthetic Heart Valves
- Previous Infective Endocarditis
- Congenital Heart Disease (CHD)
- Unrepaired cyanotic CHD
- Repaired CHD with residual defects
- Cardiac Transplant with Valvulopathy
takeaway message - F1
- do lots of blood cultures
- always consider IE in sepsis cases
- especially in high risk patients eg those with prosthetic valves
- always consider if INR has shot up (how long it takes blood to clot)
staph epidermidis
most common for prosthetics
staph aureas
IV drug user
frequently affects tricuspid
- symptoms of malaise and night sweats
strep sanguinis
tooth abcess
strep bovis
colorectal carcinoma
