2nd Exam: Pathology of Endocarditis Flashcards
When talking about endocarditis we are most often talking about:
disease of the valves
Indicate endocarditis in slides:
Fibrin, PMNs, bacteria (not NBTE, right? More lymphos)
Surgical specimen of NBTE:
incompetent valves, leaflets thickened, fibrotic, covered w sterile fibrinous vegetations
TF? All forms of endocarditis involved inflammation of the endocardium.
F. NBTE does not
How to id splenic infarct:
wedge shaped palor
NBTE leads to:
hypercoaguability and abnormal clot formation
Found in area of splenic infarct:
debris, dead tissue
Gross appearance of spleen w infarct:
Discreet area of coagulation necrosis
Infective endocarditis is characterized by:
microbial invasion of heart valves or mural myocardium
characteristic feature of endocardidits:
vegetations
Ex’s of vegetations:
necrotic debris, microorganisms, fibrin, inflammatory cells
Causes of infective endocarditis:
usually bacteria, but also fungi, Chlamydia, Coxiella, Bartonella
Predisposing factors to infective endocarditis:
degenerative valve disease (older pts), valve lesions at birth, IV drugs, before surgery and prosthetic valve replacement, vascular shunts/ grafts, vascular instrumentation, indwelling lines and catheters, systemic infections, poor oral health, chronic valve disease + dental procedures, neutropenia, immune suppression
Ex’s of indwelling lines and catheters:
PADS: pacemakers, angioplasty, dialysis, stents
Clinical presentation of infective endocarditis:
elevated ESR and CRP, EKG abnormalities, pos blood culture (10% come back neg, septic emboli, fuo, chills, fatigue, heart murmur, known source of infection, evidence of emboli, pathologic evidence of endocarditis
TF? Blood cultures of a pt w IE will come back positive almost all the time.
F. some difficult to be cultured/ sequestered in valve leaflet
Main organism that causes IE:
staph a., over 50%, high mortality w sepsis, IV drug users, acute
Infective endocarditis via Staph a., effects normal or abnormal valves?
normal
This organism is part of the normal flora, but can cause IE:
Strep viridians (and all HACEK?)
Strep viridians:
subacute (prolonged course), less virulent than Staph a., damaged valve, normal oral flora,
Infective endocarditis via Strep v., effects normal or abnormal valves?
abnormal
Organisms that lead to subacute IE:
Strep v., Strep bovis (gallolyticus), HACEK organisms (usually)
Strep bovis (gallolyticus):
subacute IE, from GI tract, (ca, polyp IBD)
HACEK organisms:
usually subacute IE, about 5%, most commonly oral source
List HACEK organisms:
Hemophilus, Actinobacillus, Cardiobacterium, Eikenella, Kingella
Vegetations form here with IE:
Valves, esp. mitral and aortic
TF? Subacute IE agents have to be more virulent than those that cause acute.
F. vice-versa
What causes heart murmur in IE?
valve leaflets covered by plaque, blood flow altered
Complications of IE:
Local extension, embolic complications
Ex’s of local extension of IE:
ring abscess, valve perforation, and insufficienty
Ex’s of embolic complications of IE:
septic emboli, distant infarcts and abscesses, splinter hemmorhages, Janeway lesions, Osler nodes, conjunctival hemmorhages/ petechiae
non-painful, small red or bleeding macular (distinct spots) or nodular lesions on palms or soles, few mm, indicative of infective endocarditis:
Janeway lesion abscess can happen in any organ
small areas of bleeding under fingernails or toenails:
splinter hemmorhages
osler nodes:
painful, red, raised lesions found on the hands and feet
In which organs can abscess form (from septic emboli?)?
any
What type of vegetation is there on the aortic valve with IE:
destructive
Acute Staph a. IE of aortic valve can lead to:
valve cusp destruction, ring abscess
Lesions in valve and myocardium, think:
IE, septic emboli, left sided endocarditis
Gives rise to persistent bacteremia in endocarditis:
organisms w/in vegetations
What are required for subacute endocarditis:
damaged valve or abnormal endothelium
difference between acute and subacute endocarditis:
time frame, not amount of damage
Why is it normally hard to get infections in heart?
Normally smooth, insult promotes clot formation and bacteria set up
Pathogenic mechs for endocarditis:
bacteremia, predisposition to infection-abnormality of endothelium, virulent microorganism in body, organisms w vegetations = persistent bacteremia
NBTE:
row of non-infective vegetations on border of valve leaflets, more lymphos than neutrophils, not inflammation/ wall to wall w cells, bland thrombus loosely attached to valve
Are neg blood cultures reliable w NBTE?
no
Basic pathological process in heart:
thombosis, NBTE
Most malignancies can make you:
hypercoagulable
Causes of cadiac valve lesions:
hypercoagulable state, aseptic thrombi on valve
Symptoms of IE are similar to:
emboli-infarcts and ischemia
How is a spleen lesion related NBTE
Infarct attributed to embolism from valve lesion
Causes of systemic emboli:
mural thrombi in heart, IE, NBTE, ath plaque
Why is difficult to fight infection in heart?
Does have its own blood supply to get pmns to fight
