Infective endocarditis
- common in pt with abnormal valves : rheumatic fever, valve
surgery/replacement/ congenital abnormalities
- common bacteria: staphylococcus aureus, strepto, psudomonas aeruginosa,
bartonella
Sample question:
A patient 40 years old male got admitted to the hospital, with fever for 7
days, will chills and rigor
Bp 120/80, pr 100bpm , T 38.5
Patient GCS 11, blur and unable to cooperate properly
On physical examination with a pansystolic murmur heard on the left
sternal border
Presence of nodules on both arms
What is your diagnosis?
Ddx: Infective endocarditis
Peripheral signs:
1. Nodes of the hand should prompt
for more history: for example any needle injection history or not prior to
this or it is just nodules. To differentiate between janeway lesion and
osler nodes.
- If they are IVDU highly suspected
IE
- generalised petechial as well due to
bacterial peritonitis
- splinter hemorrhage in proximal nail plate
- osler nodes: cause by the infection in blood stream a type of neutrophilic
vasculitis
- janeway lesion: bleeding in skin- staph aureus, microabscess from necrosis
and inflammatory infiltrate--> on palms, soles, thenear, hypothenar and
plantar surface of toes.
Central signs:
- hematuria: glomerulonephritis
- septic embolisation: lung embolisation
- Roth spots: red spot in the eye
Cardiac symptoms
2. Murmur heard at left sternal
border
- tricuspid border is related to the tricuspid regurgitation- common
on those heart valves with vegetative growth
- tricuspid valve endocarditis usually in drug abusers.
- damage by persistent bombardment of the endothelial
surface with particulate matter from injected material
- TR is accentuated with deep inspiration
- death usually from pulmonary regurgitation and RDS
or
- HF
- bradycardia
3. Fever most likely cause by the
infection
Neurological symptoms
4. Drop of GCS
- delirium - in meningitis/ encephalopathy
- confusion, drowsiness, reduced consciousness, vomiting, seizure - intracranial bleeding
- hemiparesis/aphasia: ischemic stroke
Any criteria to help with diagnosis of IE?
- Definite IE:
pathological criteria:
- microorganism demonstrated in culture/ histological examination of vegetation
- pathological lesion: confirm by histological examination with active endocarditis
clinical criteria: 2major/1major and 3minor/ 5 minor
- Possible IE: 1 major and 1 minor / 3minor
- Rejected IE: firm alternate diagnosis/ resolution of symptoms <4days antibiotic/ does not meet criteria above
- DUKEs criteria:
either 1 major 1 minor or 1 major 3 minor or 5 minor• Positive blood cultures for IE MajorEvidence of endocardial involvement Minor• Predisposition: IVDU• Fever>38• Vascular phenomena: janeway lesion• Immunologic phenomena: glomerulonephritis• Microbiologic phenomena: positive blood culture that doesnt meet major criteria
Blood Ix to be sent
- FBC: anemia, platelet count (thrombocytopenia)
- RFT: any acute kidney injury (a complication of IE)
- Electrolytes; to check if there are
any depletion that causes the gcs drop
- LFT: any liver disease:
hepatits
- Infective screening
- Urine C+S: any hematuria or UTI
- CRP, ESR: infection
- coag: if pt on anticoagulation
- Blood C+S :
1. to be taken 3 times from different sites before antibiotics/ treatment
- if remain negative for 5 days: consider negative
2. 3-4 days after commencement of treatment to document the eradication
Echocardiogram:
- irregular echo mass attached to valve
- if its tricuspid will relate to RV dilation, paradoxical septal motion and
dilated IVC
ECG: what to look out for?
- Any changes for AV block or conduction abnormalities suggesting intracardiac extension of infection
CXR: Note multiple cavitating lung nodules due to septic pulmonary emboli.
- infiltration, cavitation, pleural effusion and empyema are common in S.
aureus infection
Treatment:
- Medical
- strepto: common among the young with preexisting heart/ valve disease
- staphylo : common among old with healthcare related IE
while awaiting for investigation
- should give medical therapy first:
1. antibiotics with good coverage of staph aureus, streptococcus and
pseudomonas
-6-8 weeks of parental therapy required.
MONITOR treatment
- vital signs, regular examination
- daily ECG
- repeat echo once complete antibiotic (abx)
- review anticoagulant used
- surgical intervention
indications:
1. persistent sepsis
2. congestive heart failure
3. presented with cardiogenic shock
4. vegetation on echo >10mm in diameter
types of surgery: valve sparing debridement , valvulectomy with prosthetic
replacement
Common complications:
1. Heart Failure: valve dysfx
- Diuretics (e.g. furosemide).
- indicated for patients with symptoms of acute pulmonary oedema or fluid overload (raised jugular venous pressure; JVP and ankle oedema).
- Angiotensin converting enzyme (ACE) inhibitors.
- Beta-blockers:
- should also not be used in aortic regurgitation as this will increase diastolic time and regurgitation volume.
2. Persistent infection: causes AV block
3. Systemic embolism: occur in left sided IR within the first 2 weeks of therapy
- common sites are brain and spleen
4. neurological complications:
- early in course of IE (first 2 weeks)
- can be ischemic/hemorrhagic stroke/ aneurysm
- to w/hold anticoagulation base on severity of complication
Prophylaxis
1. Antimicrobial prophylaxis not encouraged for cardiac patients
2. to consult with dentist prior invasive dental/medical procedure regarding the risk from IE
3. maintain good oral and skin hygiene
Reference:
