Mecahism by which injury leads to valve vegetation formation
Endothelial injury usually occurs due to turbulent blood flow resulting from a pre-existing valvular disease
Endothelial injury may also occur due to foreign material within circulation-- venous catheters/ prosthetic heart valves
Once endothelial surface is exposed, platelets adhere to collaged and initiate the formation of a sterile thrombus -- Nonbacterial thrombotic endocarditis (NBTE)
List the common pathogens that cause infection for endocarditis
1. Staphylococci Aureus ( more virulent)
2. Streptococci ( specifically Viridans)
3. HACEK bacteria: Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, and Kingella)
- oral cavity
4. Acute Rheumatic Fever : Group A beta-hemolytic stretpococcal infection (GABH) -- starts as pharyngitis
Note that in a rural area with not IV drug users, Strep Viradans infection is greater than staph aureus
Mechanism for infections endocarditis
Formation of thrombus ( NBTE -- nonbacterial thrombotic endocarditis) is caused by endothelial injury that caused platelets to aggregate and form a sterile thrombus through fibrin deposition.
Fibrin-platelet deposit = surface of adherence by bacteria.
Fibrin then covers organisms and protects them from host defenses by inhibiting chemotadis and migraiton of phagocytes
Acute Endocarditis Clinical Presentation:
Acute onset of high-grade fever and shaking chills
Rapid onset of Cardiac Heart failure due to structural damage
- rapid valve failure
HIghly virulent organism attacking a normal valve
* Cerebellar complications -- large mobile and on mitral valve
High morbidity and mortality even with appropriate therapy/surgery
Subacute endocarditis Clinical Presentation
Low grade fever with non-specific fatigue, anorexia, weight loss, and "flu-like" symptoms
* fever may be absent in elderly
Less virulent organims but also happens due to an already abnormal valve
* Aortic valve (most common), Mitral valve (2nd common)
Tricuspid Valve ( tricuspid regurgitation) -- IV drug users
Endocarditis is assumed to be correct diagnosis (until proven otherwise) when what two criteria are present?
New regurgitant murmur + Recurrent/ unremitting fever
Clinical Features of infectious Endocarditis -- physical findings
1. Osler nodes: painful fingertip nodules
2. Janeway Lesion : painless palm or sole erythematous lesion
3. Splinter Hemorrhages: petechia nail bed
4. Roth Spots: Retinal hemorrhage
4. 90% of patients have a murmur
Rheumatic Fever Clinical features:
1. who does it affect?
2. when does it present?
Children
2-3 weeks after streptococcal infection
Rheumatic Fever major criteria:
JONES
J- Joints : polyarthritis : swelling, redness, warmth, tenderness
O-- carditis -- aortic or mitral regurgitation
N--Nodules (subcutaneous)
E-- Erythema marginatum
S-- Sydenham chorea: uncoordinated involuntary purposeless movements
- patient cannot maintain clenched fists
Rheumatic fever minor criteria:
CAFE PAL
C-- CRP increased
A-- Arthralgia
F-- Fever
E-- Elevated ESR
P -- Prolonged PR interval
L-- Leukocytosis
What are the requirements needed to diagnose RF?
2 major criteria
OR
1 major criteria and 2 Minor criterias
* throat culture and take blood titers of antibody. ** GO WITH BLOOD TITERS**
Recall that patients come 2-3 weeks after suffering from RF -- may no longer be in throat
