Infective Endocarditis Flashcards
(24 cards)
What is infective endocarditis
Inflammatory disease of the heart
One of the most serious
Characterized by colonization or invasion of the _______or the __________ by ______________ agents
Heart valves
Mural endothelium
Microbiological agents
Microbiological agents form ______, __________ with microbiological agents
Bulky, friable vegetations
Other sites it can affect include
Aorta, aneurysmal vessels
List the 2 clinical subtypes
Acute and subacute
Acute;
List the organism involved
Normal/ damaged valve
High or low virulence
Death in how many percent
Staph aureus
Destructive infection on previously normal valve
High virulence
50%
SubAcute;
List the organism involved
Normal/ damaged valve
High or low virulence
Death in how many percent
S viridans
Previously damaged valves
Low virulence
Patients recover after appropriate antibiotic therapy
Predisposing cardiac conditions to infective endocarditis
Rheumatic heart disease
Congenital heart disease
Myxomatous mitral disease
Degenerative Calcific valvular stenosis
Systemic conditions leading to IE
Neutropenia
Immunodeficiency state ( HIV)
Diabetes mellitus
Chronic alcoholism
Indwelling catheters (intracardiac and intravascular)
Drug abusers (injection)
Implicated organisms include
Bacteria
Strep viridans, S faecalis
Staph
S pneumoniae
Gram neg organisms: E. coli
Viruses
Fungi
Morphology
Friable , bulky vegetations on the heart valve
Ring abscess of the valves
Organization and fibrosis
Clinical course
Usually non specific
Fever
Malaise
Weight loss
Petechial haemorrhage
Subungal haemorrhage (injury of the nail bed)
Roth’s spot
Roth’s spot
Embolism of the central area of the retina may cause canoe shaped haemorrhagic spot with pale centre
Complications of infective endocarditis
Cardiac
Valvular insufficiency with cardiac failure
Myocardial ring abscess with perforations
Suppurative pericarditis
Dehiscence of artificial valves
Extracardiac complications
Emboli with septic infarcts of
Brain
Spleen
Kidneys
Lungs (pneumonia abscess)
Renal complications
Embolic infarcts
Focal GNitis leading to nephrotic syndrome and renal failure
Diffuse Gnitis due to Ag -Ab complex formation
Multiple renal abscess with staphylococci
Diagnosis :
Clinical and laboratory
Clinical: take a good history
Observe clinical features
Do a cardiac examination
Laboratory
Blood culture: this may harvest any of the causative organisms
Non bacterial thrombotic endocarditis is also called
Marantic endocarditis
NBTE
Vegetations are seen in _____
Patients with debilitating illness
NBTE is associated with
Mucinous adenocarcinoma
Mucin has a pro coagulant effect
Also associated with promyelocytic leukemia
Hyperestrogenic state
Morphology of NBTE
Deposition of small sterile fibrin masses in valve leaflets that are normal and vegetations do not contain microorganisms
NBTE mostly affects what valves
Aortic and mitral valves
May cause embolism
Liebman- sacks disease
Mitral and tricuspid valvulitis occurring in SLE
Morphology of LSD
Lesions are small
Sterile and granular
Located in under surface of AV valves
Consists of eosinophilia material that contains haematoxylin bodies
Intense valvulitis with fibrinoid necrosis
Vegetations rarely embolises but becomes fibrosed
