infective endocarditis ug- 23 feb 2017
TRANSCRIPT
• “…..increases the physician's interest in the development of an infectious process". William Bart Osler, 1893
• One century age- 100% fatal- diagnosis only post-mortem
• Diagnosis- 1994- David Durack et al- Duke university gave a criteria
• Now- real time imaging and diagnosis with effective treatment
Infective endocarditis- Bacterial endocarditis in children
Basics
Objectives
• Basic pathogenesis
• Clinical features
• Diagnosis
• Treatment
• Summary
What is endocarditis?
• Infection and inflammation of the inner layer of the heart- endocardium
• Valvular surfaces commonly involved
Pathogenesis
Damaged cardiac endothelium (usually
over the valves)-produced by turbulent jet
flow- thrombotic foci
Nidus
Bacteremia Vegetation
High risk groups
• Intravenous drug abusers- right heart valves
• Immunocompromised
• Heart diseases:
– High velocity jet- VSD, AS, bicuspid aortic valve, MVP
– Uncorrected Cyanotic congenital heart disease
• Prosthetic heart valves, post cardiac surgery
• Indwelling venous catheters
Microbiology
• Gram positive organisms- most common- bind to fibronectin easily
• Gram positive:
– Streptococcus viridans
– Staphylococcus aureus, Staphylococcus epidermidis
– Enterococci
• Gram negative:
– HACEK group- Haemophilus sp, Actinobacillus sp, Cardiobacterium sp, Eikenella sp, and Kingella kingae
Clinical features
IE C/F
Bacteremia
Fever, Malaise
Local valve destruction
Acute cardiac failure
New or changing murmurs
Immune complex
formation
Glomerulonephritis
Osler nodes
Roth spots
Septic embolization
Hands- Janeway lesions, Splinter hemorrhages
Osteomyelitis, Septic arthritis
Pneumonia
Brain abscess
Infarcts
Others
• Splenomegaly
• Clubbing
Diagnosis• Consider IE- child with heart disease with an
unexplained fever
• Blood culture- vital
– Good volume- 1- 3 mL in infants; 5- 7 mL in older children
– Not necessary to time with fever- bacteremia in IE continuous
– 3 aerobic cultures over the first day before administering antibiotics
Modified Duke’s criteria
Modified Duke’s criteria
• Combination of clinical, microbiologic, and echocardiographic criteria
A, B- Splinter hemorrhages
C- Osler nodes-tender
erythematous nodules located in pulp of fingers
and toes
D- Janeway lesions- flat
painless bluish red spots on
palms and soles
Treatment• Empirical treatment- Crystalline penicillin G plus
Gentamicin
• Alternate- Ceftriaxone plus Gentamicin
• Prosthetic valve/ Staphylococcal endocarditis-Vancomycin plus Gentamicin
• Duration of therapy- 4- 6 weeks
• Modify regimen based on response and sensitivity pattern
Prevention• High risk heart conditions:
– Prosthetic cardiac valve – History of infective endocarditis – Congenital heart disease (CHD): (1) unrepaired cyanotic
CHD, including palliative shunts, (2) completely repaired congenital heart defect with prosthetic material or device, whether placed by surgery or by catheter intervention- first 6 months after the procedure, (3) repaired CHD with residual defects at the site or adjacent to the site of a prosthetic patch or prosthetic device
– Cardiac transplantation recipients
Except for the conditions listed, antibiotic prophylaxis is no longer recommended for any other form of CHD
High risk procedures
• Dental: single dose of oral amoxicillin
No if:
Placement of orthodontic brackets
Shedding of milk teeth
Bleeding from trauma to the lips or oral mucosa
Yes if :
Manipulation of gums/ periapicalregion of teeth/ perforation of
the mucosa
Others
• RS- yes for invasive respiratory tract procedures that involve incision or biopsy of the respiratory mucosa (eg, tonsillectomy, adenoidectomy, abscess drainage)- not recommended for bronchoscopy- single dose of oral amoxicillin
• Surgical procedure that involves infected skin, skin structure, or musculoskeletal tissue- yes-Antibiotic active against staphylococci and beta-hemolytic streptococci (eg, cloxacillin or cephalosporin)
• Genitourinary/ GIT procedures- No
Take home messages
• Etiologic agents of IE
• Pathogenesis
• When to suspect IE- any child with heart disease and unexplained fever
• Clinical features
• Modified Duke’s criteria
• Treatment and prevention