Infective Endocarditis (IE) Flashcards
WHERE in the heart can IE be CONTRACTED?
Infection of:
1) Valves - Native or Prosthetic
2) Endocardium
3) Interventricular Septum, i.e. Septal Defect
4) Intra-Cardiac Devices
5) Chordae Tendinae
What are the some of the RISK FACTORS of IE?
1) Valvular Disease
2) > Age
3) Congenital Defects
4) Rheumatic Fever
5) Healthcare-Associated Infection
6) Invasive Procedures
7) Intra-Cardiac Devices
8) IV Drug Abuse (IVDA)
9) Immunocompromised Patients
10) Diabetes
Describe the PATHOPHYSIOLOGY of IE:
1) Damage or Inflammation of Endothelial Lining
2) Adherence + Colonisation of Bacteria to Fibrin-Platelet Clot
3) Inflammatory Mediators Mobilised
4) Activation of Coagulation Cascade
5) Vegetation Growth
How can BACTERAEMIA occur and spread?
1) Extra-Cardiac Infections
2) Invasive Procedures
3) Gingival Disease
4) Activities of Daily Living, i.e. Brushing Teeth
What are the SYMPTOMS of IE?
*Can be Variable and Non-Specific
1) Fever
2) Fatigue
3) Malaise
What is the MAIN CAUSE of IE?
Bacteraemia
What are some of the IMMUNE COMPLEX DEPOSITION SIGNS of IE?
1) Splinter Haemorrhages
2) Janeway Lesions
3) Roth Spots
4) Osler’s Nodes
5) Vasculitis Rash
What are some of the SEPTIC SIGNS of IE?
1) Pyrexia
2) Weight Loss
3) Night Sweats
4) Rigors
5) Anaemia
6) Splenomegaly
7) Clubbing
What are the potential SIGNS of IE due to CARDIAC LESIONS?
Change to Pre-Existing or New Murmurs
What are the OTHER potential SIGNS of IE?
1) Embolic Phenomena - PEs/Abscesses or Peripheral Emboli/Abscesses
2) Focal Neurological Signs
Under what CIRCUMSTANCES may SIGNS of IE be ABSENT?
1) In the Elderly
2) After Antibiotic Treatment
3) < Virulent/Atypical Organisms
4) Immunocompromised
What INVESTIGATIONS should be carried out to DIAGNOSE IE?
1) FBC - U + Es; Neutrophilia; CRP; ESR
2) Blood Cultures
3) Urinalysis
4) ECG
5) CXR
6) Echo - Transthoracic (TTE) + or - Transoesophageal (TOE)
What is the MAIN CRITERIA for BLOOD acquisition and subsequent CULTURING when diagnosing IE?
Obtain:
1) Prior to Commencing Antibiotics
2) 3 Sets
3) From Different Sites
4) > 6 Hours Apart
What might be evident on CXR for IE?
1) Congestive Heart Failure
2) PEs/Abscesses
What is the FIRST-LINE MODE of echocardiography for IE?
TTE
*Perform TOE if TTE is -ve; yet, > Clinical Suspicion Remains
What are the MAIN PATHOGENS involved in IE and are likely to return +ve in BLOOD CULTURES?
1) Streptococci - Strep. Viridans and Bovis
2) Enterococci
3) Staphylococci - Staph. Aureus and Epidermidis
What would be the REASONS for a -ve BLOOD CULTURE RESULT in IE?
1) Prior Antibiotic Treatment
2) Fastidious Organisms - i.e. Gram -ve Bacilli or Fungi
3) Intracellular Bacteria
What are the MAJOR CRITERIA for diagnosing IE according to DUKE CRITERIA?
1) Identification of an Organism via +ve Blood Cultures
2) Evidence of Infection in the Heart via Echo or Murmurs
What are some of the MINOR CRITERIA for diagnosing IE according to DUKE CRITERIA?
1) Predisposition
2) Pyrexia
3) Vascular Phenomena, i.e. Emboli
4) Immunological Phenomena, i.e. Osler’s Nodes
In order to obtain a DEFINITE diagnosis, which criteria MUST BE FULFILLED?
1) 2 Majors
2) 1 Major + 3 Minors
3) 5 Minors
What are the TREATMENTS for IE?
1) IV Antibiotics *After Blood Cultures
2) + or - Surgery
If IE pertains to NATIVE VALVES, which ANTIBIOTICS should be given?
*For 4 Weeks
Gentamicin + Amoxicillin
If IE pertains to NATIVE VALVES and PENICILLIN ALLERGIC, which ANTIBIOTICS should be given
*For 4 Weeks
Gentamicin + Vancomycin
If IE pertains to PROSTHETIC VALVES, which ANTIBIOTICS should be given?
*For 6 Weeks
Gentamicin + Vancomycin + Rifampicin
What are some of the COMPLICATIONS of IE; thus, INDICATIONS for SURGERY?
1) Heart Failure
2) Leaflet Perforation
3) Uncontrolled Infection
4) Abscess Formation
5) AV Heart Block
6) Embolism
7) Prosthetic Valve Dysfunction/Dehiscence
What does the EVIDENCE SUGGEST regarding the use of PROPHYLACTIC ANTIBIOTICS to prevent IE?
1) Unfounded Effectiveness
2) Should be Avoided
3) Limit to > Risk Patients
4) > Risk of Anaphylaxis
5) > Prevalence of Antibiotic Resistance
What PREVENTATIVE GUIDANCE should be OFFERED to AVOID IE in those at risk?
1) Benefits and Risks of Prophylaxis
2) Good Oral Health
3) Symptoms that Indicate IE
4) When to Seek Expert Advice
5) Risks of Invasive Procedures; Including Non-Medical, i.e. Piercing or Tattooing
