Endocarditis Flashcards
A 53 y/o homeless, alcoholic, male was admitted with a right hemiparesis. He had been seen in the ER two weeks ago and again one week ago after being picked up in the street by the police. He was found to have a fever of 38.3 degrees centigrade (101F) on both occasions. He was also found to be covered by body lice in each instance. A total of 6 blood cultures had been negative. Physical exam upon admission revealed a temperature of 39 degrees C, a diastolic descrendo murmur at Erbs area, and negative repeat blood cultures.
Fever of unidentified origin
Rule of threes
Three office visits, 3 weeks of fever, 38.3 C
Negative workup
Fever of unidentified origin
Primary causes of FUO
**Infection (TB and endocarditis, occult abscess)
Cancer (lymphoma, leukemia)
Autoimmune/Connective Tissue Disease (Still’s disease, SLE, cryoglobulinemia, PAN)
Miscellaneous (sarcoid, FMF, Whipples, thyroiditis)
Undetermined
What causes the fever
IL1, IL6, TNFα -> produce PGE2 via endothelial and glial receptor stimulation -> stimulate hypothalamus to produce fever
Modified Duke criteria for endocarditis
1) Two major out of three criteria of:
Two positive blood cultures
Echo evidence of endocardial involvement
New regurgitant murmur
2) One major and 3 minor or 5 minor, with minor being:
Predisposing condition
Fever of 38 degrees or higher
Vascular emboli (the actual bug): Janeway lesion, splinter hemorrhages (nails), mycotic aneurysm, conjunctival or cutaneous hemorrhage, PE, stroke, MI, etc.
Immunologic phenomena (IC deposition): Osler node, Roth spots, RF, GN (hematuria and proteinuria)
Janeway lesion
Flat, painless, septic microemboli
Hands and feet
Osler node
Painful and vasculitic
Can form anywhere
Roth spots
Retinal hemorrhages
Set up for infective endocarditis
Regurgitant valves, bicuspid valves, rheumatic valves, calcific valves, MVP, PDA, Coarctation, VSD
Acute endocarditis with virulent organisms
Valvular regurgitation, high fever, early embolization
Native valve endocarditis
Transient bacteremia as from brushing teeth to IV devices
Bacteria land on troubled valve
Bacteria most likely to cause native valve endocarditis
Staphylococcus
May also be Strep viridans or bovis, group D streptococcus or HACEK
IV drug users get endocarditis from
Staph
Then enterococcus and strep
Valve most effected in IV drug users
Tricispid valve
Prosthetic valve endocarditis (early and late)
Early - coagulase + and – staphylococcus
Late - streptococcusor or staph
What if culture is negative
1) Fungi
2) Need special media - Legionella, Bartonella, and Abiotrophia
3) No growth on artificial media - Tropheryma whipelli, Q fever or psittacosis pathogens
4) Slow growing with prolonged incubation - Brucella, anaerobes, HACEK
Eikenella corrodens
Aggregatibacter (Haemophilus) aphrophilus, Aggregatibacter (Acintobacillus) actinomcetemcomitans, Cardiobacterium hominis, Kingella
How to diagnose endocarditis
Draw 3 cultures one hour apart
2 positives
3 if skin contamination - coag neg staph
A patient, who works for a computer company and has a history of a prosthetic aortic valve, has had a low grade fever, a new diastolic murmur at the aortic area and negative blood cultures for the past three months. Cardiac ECHO has shown no vegetations, but an abdominal aortic aneurysm was accidentally found. He has had a cat for 10 years. He is positive for RF.
Endocarditis from Coxiella burnetii
Complications of endocarditis
Heart block, CHF, emboli, mycotic aneurysms, myocardial abscess
Specific treatment of endocarditis
Acute Coxiella infection - Doxycycline Chronic infection - Doxycycline Bartonella hensalae or quintana - Doxycline Streptococcus endocarditis - Penicillin Enterococcal endocarditis - Penicillin plus gentamicin (risk of renal failure) Staphylococcus endocarditis - Nafcillin Methicillin resistant – Vancomycin Surgery
Treatment of endocarditis before cultures
Native valve: Vancomycin
Prosthetic valve: Vancomycin, Gentamycin, Rifampin
Surgery consult, especially in prosthetic valve endocarditis
Why do you use Rifampin?
It kills staph adhered to foreign material (like prosthetic valve)
Antibacterial effect of Vancomycin
Interrupt cell wall synthesis
Antibacterial effect of Gentamycin
Disrupt protein synthesis
Antibacterial effect of Rifampin
DNA Dependent RNA Polymerase
Streptococcus bovis
GI neoplasms
Streptococcus mutans
Poor dentition
Enterococci
Elderly with urinary problems
HACEK
Prolonged incubation
Late prosthetic valve (>2 mo)
Streptococcus
IV drug users
Staph aureus (or epidermis)
Alcoholics and street people
Bartonella
No growth
Tropheryma, Q fever
Endocarditis Prophylaxis
High risk cardiac populations - Previous IE, Prosthetic valves or material, and Cyanotic congenital heart disease - Tetralogy of Fallot, Eisenmenger syndrome
Only for perforating procedures of - Teeth, Lungs, and Skin
Antibiotic before dental procedure
Amoxicillin 2 grams 1 hour
A 35 y/o female presents with fever, weight loss, leukocytosis, elevated sed rate, elevated RF, and episodic pulmonary edema and syncope, especially with standing (occludes mitral valve). The patient had a recent stroke. A physical exam shows a diastolic rumble with an occasional diastolic extra sound at the mitral valve area upon standing. There is a lesion resembling an Osler node on her right great toe. This patient most likely has an:
Atrial Myxoma
Can present like endocarditis
Myxoma vs endocarditis
Syncope true to myxoma
Atrial myxoma
Seen in Carney complex of pigmented skin lesions and endocrine neoplasia. Looks like a systemic illness with emboli-usually left atrium. Diastolic tumor plop and rumble, upright CHF. Cause is related to a cAMP activated protein kinase A with activated cell proliferation (PRKAR1A gene); a multiple neoplasia syndrome.
