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Old 06-29-2011
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Heart prophylaxis for Infective endocarditis

prophylaxis for Infective endocarditis look at difference in kaplan notes

PEDIATRIC page 140

Internal medicine page 225


for god sake any one can explain

for example in kaplan pediatric they said give prophylaxis for cystoscopy and prostatic surgery

but in Internal medicine they says no need for prophylaxis for previous two procedure
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what about rigid bronchoscopy in kaplan they say no need page 225

in MTB PAGE 32 ,,,,, flexibel bronchoscopy even with biopsy .
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Default IE case 1

A 55-year-old man presents to the emergency department with a 2-week history of fevers, chills, weakness, and shortness of breath. He was previously well and does not take any regular medications. On arrival, his blood pressure, is 130/70 mm Hg; pulse, 110 beats/min; temperature 39.3°C (102.7°F); and respirations, 32 breaths/min. Linear, red streaks are seen under the fingernails and are most prominent in the proximal nail bed. There is a pansystolic murmur heard over the apex that was not noticed 6 months ago during his annual health maintenance examination. An echocardiogram is performed and reveals mitral valve vegetations. Blood cultures are drawn. While awaiting results from the blood cultures, what is the most appropriate antibiotic regimen?

Answer Choices Correct answer Your answer
A. Ceftriaxone
B. Nafcillin, penicillin, gentamicin
C. Nafcillin, vancomycin
D. Penicillin
E. Vancomycin, gentamicin, rifampin
Explanation
Option B (Nafcillin, penicillin, gentamicin) is correct. This patient has infective endocarditis (IE) and is otherwise healthy. He is not predisposed to any unusual organisms and thus, the most appropriate empiric coverage is with nafcillin, penicillin, and gentamicin. This provides adequate coverage for the most likely causes of IE, including Staphylococcus, Streptococcus, and Enterococcus.

Option A (Ceftriaxone) is incorrect. Ceftriaxone is useful as outpatient therapy in patients who have Streptococcus viridans-associated IE.

Option C (Nafcillin, vancomycin) is incorrect. This is not appropriate empiric coverage for any situation as there is insufficient coverage of gram-negative organisms.

Option D (Penicillin) is incorrect. Monotherapy with penicillin can be started after the causative agent, usually Streptococcus viridans or Streptococcus bovis, has been identified as susceptible.

Option E (Vancomycin, gentamicin, rifampin) is incorrect. This is appropriate empiric coverage for patients who have prosthetic heart valves and are more likely to have gram-negative infections, as well as the more common Staphylococcus aureus and Staphylococcus epidermidis.

High-yield Hit 1
MANAGEMENT
Medical:
Box 8-2 describes antibiotic treatment of adults, based on positive blood culture results.
Antibiotic therapy (after identification of the organism) should be guided by susceptibility testing (minimum inhibitory concentration, minimum bactericidal concentration).
Peak serum bactericidal titers of 1:64 or greater and trough bactericidal titers of 1:32 or greater are recommended.
Initial intravenous antibiotic therapy (before culture results) is aimed at the most likely organism.
In patients with prosthetic valves or patients with native valves but allergic to penicillin: vancomycin plus rifampin and gentamicin
In intravenous drug addicts: penicillinase-resistant penicillin (oxacillin or nafcillin) plus gentamicin
In native-valve endocarditis: combination of penicillin and gentamicin; a penicillinase-resistant penicillin or vancomycin should be added if acute bacterial endocarditis is present or if S. aureus is suspected as one of the possible causative organisms; the combination of vancomycin and gentamicin provides broad empiric coverage while awaiting culture results.
Surgical: indications for cardiac surgery in patients with active native valve infective endocarditis are listed in Box 8-3. Box 8-4 describes indications for surgery in patients with prosthetic valve endocarditis.

From Practical Guide to the Care of the Medical Patient 7E by Ferri
High-yield Hit 2
BOX 8-2 Antibiotic Treatment of Infective Endocarditis
Streptococci
Viridans streptococci and Streptococcus bovis
Penicillin G susceptible (MIC ≤0.1 μg/mL)
Regimen A: Penicillin G at 12-18 million U/d IV in divided doses q4h for 4 weeks
Regimen B: Penicillin as in regimen A plus gentamicin 1 mg/kg IV q8h both for 2 weeks
Regimen C: Penicillin plus gentamicin for 2 weeks as in regimen B with penicillin continued 2 weeks longer
*Regimen D: Ceftriaxone at 2 g IV or IM daily for 4 weeks
*Regimen E: Vancomycin at 15 mg/kg IV q12h for 4 weeks
Relatively penicillin G resistant (MIC >0.1 μg/mL but <0.5 μg/mL)
Regimen C
*Regimen D or E
Enterococci and viridans streptococci (MIC ≥0.5 μg/mL)
Regimen F: Penicillin G 18-30 million U/d or ampicillin at 12 g/d IV in divided doses q4h, plus gentamicin at 1 mg/kg IV q8h or streptomycin at 7.5 mg/kg IM q12h, both for 4 to 6 weeks
*Regimen G: Vancomycin at 15 mg/kg IV q12h plus gentamicin or streptomycin as in regimen F, both for 4 to 6 weeks
Prosthetic valve (see text)
Staphylococci
Native valve
Methicillin susceptible (Staphylococcus epidermidis, Staphylococcus aureus)
Regimen H: Nafcillin at 2 g IV q4h for 4 to 6 weeks with or without gentamicin 1 mg/kg IV q8h for the first 3 to 5 days
*Regimen I: Cefazolin at 2 g IV q8h for 4 to 6 weeks with or without gentamicin as in regimen H
Regimen J: Vancomycin at 15 mg/kg IV q12h for 4 to 6 weeks
Methicillin resistant
Regimen J
Prosthetic valve
Methicillin susceptible
Regimen H, I, or J: for 6 to 8 weeks with gentamicin for the first 2 weeks and rifampin at 300 mg orally q8h for 6 to 8 weeks
Methicillin resistant
Regimen J: for 6 to 8 weeks with gentamicin for the first 2 weeks and rifampin at 300 mg orally q8h for 6 to 8 weeks

*Regimens for patients allergic to penicillin.
MIC, minimal inhibitory concentration.
From Gorbach SL: Infectious Diseases, 2nd ed. Philadelphia, WB Saunders, 1998.
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Default IF case 2

A 39-year-old woman is referred to the physician by the dentist, because the dentist discovered a heart murmur on physical examination prior to a pulpectomy. She states that she has known for many years that she has had some form of heart murmur but cannot recall the exact type. On examination, there is a midsystolic click best heard at the apex that radiates into the axilla. An echocardiogram reveals mitral leaflet displacement greater than 4mm above the plane of the mitral annulus, normal leaflet thickness, and no retrograde flow through the mitral valve. What is the most appropriate management for this patient in regard to her dental pulpectomy?

Answer Choices Correct answer Your answer
A. Amoxicillin
B. Clindamycin
C. Gentamicin
D. No further management required
E. Vancomycin and gentamicin
Explanation
Option D (No further management required) is correct. Mitral valve prolapse is likely to be one of the most complicated scenarios for infective endocarditis (IE) prophylaxis on the exam. In asymptomatic mitral valve prolapse without valvular thickening or mitral regurgitation, prophylaxis is not required.

Option A (Amoxicillin) is incorrect. If the valve leaflets were thickened or there was evidence of mitral regurgitation, amoxicillin prophylaxis against IE would have been indicated.

Option B (Clindamycin) is incorrect. Clindamycin is used as prophylaxis for dental procedures in patients who are allergic to penicillin.

Option C (Gentamicin) is incorrect. Gentamicin is not used as monotherapy for prophylaxis against IE.

Option E (Vancomycin and gentamicin) is incorrect. This would be appropriate antibiotic therapy in patients who have a penicillin allergy, are at high risk for developing IE and are undergoing a gastrointestinal or genitourinary procedure.

High-yield Hit 1
DIAGNOSTIC CRITERIA FOR INFECTIVE ENDOCARDITIS
The modified Duke criteria for the diagnosis of infective endocarditis are described in Table 8-7.
Table 8-7. Modified Duke Criteria for the Diagnosis of Infective Endocarditis* Comments
Criteria Comments
Major criteria
Microbiologic
Typical microorganism isolated from two separate blood cultures: viridans streptococci, Streptococcus bovis, HACEK group, Staphylococcus aureus, or community-acquired enterococcal bacteremia without a primary focus
or In patients with possible infective endocarditis, at least two sets of cultures of blood collected by separate venipunctures should be obtained within the first 1 to 2 hours of presentation. Patients with cardiovascular collapse should have three cultures of blood obtained at 5- to 10-minute intervals and thereafter receive empirical antibiotic therapy.
Microorganism consistent with infective endocarditis isolated from persistently positive blood cultures
or
Single positive blood culture for Coxiella burnetii or phase I IgG antibody titer to C. burnetii >1:800 C. burnetii is not readily cultivated in most clinical microbiology laboratories.
Evidence of endocardial involvement
New valvular regurgitation (increase or change in preexisting murmur not sufficient)
or
Positive echocardiogram (transesophageal echocardiogram recommended in patients who have a prosthetic valve, who are rated as having at least possible infective endocarditis by clinical criteria, or who have complicated infective endocarditis) Three echocardiographic findings qualify as major criteria: a discrete, echogenic, oscillating intracardiac mass located at a site of endocardial injury; a periannular abscess; and a new dehiscence of a prosthetic valve.
Predisposition to infective endocarditis that includes certain cardiac conditions and injection-drug use Cardiac abnormalities that are associated with infective endocarditis are classified into three groups:
High-risk conditions: previous infective endocarditis, aortic-valve disease, rheumatic heart disease, prosthetic heart valve, coarctation of the aorta, and complex cyanotic congenital heart diseases
Moderate-risk conditions: mitral-valve prolapse with valvular regurgitation or leaflet thickening, isolated mitral stenosis, tricuspid-valve disease, pulmonary stenosis, and hypertrophic cardiomyopathy
Low- or no-risk conditions: secundum atrial septal defect, ischemic heart disease, previous coronary-artery bypass graft surgery, and mitral-valve prolapse with thin leaflets in the absence of regurgitation
Fever Temperature >38° C (100.4° F)
Vascular phenomena Petechiae and splinter hemorrhages are excluded. None of the peripheral lesions are pathognomonic for infective endocarditis.
Immunologic phenomena Presence of rheumatoid factor, glomerulonephritis, Osler's nodes, or Roth's spots
Microbiologic findings Positive blood cultures that do not meet the major criteria
Serologic evidence of active infection; single isolates of coagulase-negative staphylococci and organisms that very rarely cause infective endocarditis are excluded from this category.

*Criteria are adapted from Li JS, Sexton DJ, Mick N, et al: Proposed modifications to the Duke criteria for the diagnosis of infective endocarditis. Clin Infect Dis 30:633-638, 2000.
Cases are defined clinically as definite if they fulfill two major criteria, one major criterion plus three minor criteria, or five minor criteria; they are defined as possible if they fulfill one major and one minor criterion, or three minor criteria.
HACEK, Haemophilus species (Haemophilus parainfluenzae, H. aphrophilus, and H. paraphrophilus), Actinobacillus actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, and Kingella kingae.
SPECIAL DIAGNOSTIC CONSIDERATIONS
Right-sided endocarditis
Usually seen in intravenous drug users.
Physical examination: may reveal a murmur of tricuspid regurgitation (holosystolic, heard at left lower sternal border, increased by inspiration, decreased by expiration and Valsalva's maneuver); evidence of failure of right side of heart may also be present (neck vein distention, congestive hepatomegaly, edema).
Blood cultures: S. aureus (50% of cases), streptococci and enterococci (20% of all cases), and gram-negative bacilli (approximately 10% of cases)
Chest x-ray: may demonstrate peripheral wedge-shaped infiltrates with cavitation (septic pulmonary emboli).
Right-sided endocarditis is less aggressive than left-sided disease; the prognosis for patients with isolated tricuspid valve endocarditis caused by S. aureus is generally favorable, with good response to medical therapy. A penicillase-resistant penicillin (e.g., cloxacillin 2 g IV q4h) is effective for most patients with isolated tricuspid endocarditis caused by methicillin-susceptible S. aureus. Ceftriaxone is frequently used for outpatient intravenous therapy (if S. aureus is sensitive), since it can be given once daily.
Prosthetic valve endocarditis
Overall frequency is approximately 2%.
Overall mortality rate is 59%.
The microbiologic agent involved and the mortality rate are related to the time of onset of endocarditis after cardiac valve implantation.
Early-onset prosthetic valve endocarditis (within 2 months of implantation)
(a) Frequency of endocarditis is 0.78%.
(b) Usually resulting from surgical infection
(c) Staphylococci are the most common organisms (S. epidermidis the predominant one); they are usually resistant to cephalosporins and semisynthetic penicillinase-resistant penicillins.
(d) Mortality rate is 77%.
(e) Replacement of the valve is usually necessary.
Late-onset prosthetic valve endocarditis (occurring more than 2 months postoperatively)
(a) Frequency of endocarditis is 1.1%.
(b) Usually community-acquired infection
(c) Streptococci are the predominant organisms.
(d) Overall mortality rate is 46%.
Streptococcus bovis endocarditis
Often associated with large bowel lesion, frequently carcinoma
A gastrointestinal work-up should be undertaken.
MAJOR COMPLICATIONS OF INFECTIVE ENDOCARDITIS
Congestive heart failure caused by valvular destruction or associated myocarditis
Embolism
Central nervous system (CNS): hemiplegia, sensory loss, aphasia, meningeal irritation, mycotic aneurysm, brain abscesses, seizures, headaches, cerebral hemorrhage (from rupture mycotic aneurysm or stroke)
Kidneys: hematuria resulting from focal glomerulonephritis, renal failure resulting from diffuse proliferative glomerulonephritis, renal emboli, and infarction
Coronary arteries: heart failure, angina, myocardial infarction
Spleen: splenic infarct
Musculoskeletal: osteomyelitis and infectious arthritis also possible embolic phenomena
Anticoagulation therapy has not been shown to prevent embolization in patients with infective endocarditis. It increases the risk of intracerebral hemorrhage and is contraindicated.
Arrhythmias, various degrees of heart block
Pericarditis, myocardial abscess (perivalvular abscess), myocarditis
MANAGEMENT
Medical:
Box 8-2 describes antibiotic treatment of adults, based on positive blood culture results.
Antibiotic therapy (after identification of the organism) should be guided by susceptibility testing (minimum inhibitory concentration, minimum bactericidal concentration).
Peak serum bactericidal titers of 1:64 or greater and trough bactericidal titers of 1:32 or greater are recommended.
Initial intravenous antibiotic therapy (before culture results) is aimed at the most likely organism.
In patients with prosthetic valves or patients with native valves but allergic to penicillin: vancomycin plus rifampin and gentamicin
In intravenous drug addicts: penicillinase-resistant penicillin (oxacillin or nafcillin) plus gentamicin
In native-valve endocarditis: combination of penicillin and gentamicin; a penicillinase-resistant penicillin or vancomycin should be added if acute bacterial endocarditis is present or if S. aureus is suspected as one of the possible causative organisms; the combination of vancomycin and gentamicin provides broad empiric coverage while awaiting culture results.
Surgical: indications for cardiac surgery in patients with active native valve infective endocarditis are listed in Box 8-3. Box 8-4 describes indications for surgery in patients with prosthetic valve endocarditis.
PROPHYLAXIS OF INFECTIVE ENDOCARDITIS
Cardiac conditions associated with endocarditis are described in Box 8-5.
Prophylactic regimens for various procedures are described in Table 8-8.
BOX 8-2 Antibiotic Treatment of Infective Endocarditis
Streptococci
Viridans streptococci and Streptococcus bovis
Penicillin G susceptible (MIC ≤0.1 μg/mL)
Regimen A: Penicillin G at 12-18 million U/d IV in divided doses q4h for 4 weeks
Regimen B: Penicillin as in regimen A plus gentamicin 1 mg/kg IV q8h both for 2 weeks
Regimen C: Penicillin plus gentamicin for 2 weeks as in regimen B with penicillin continued 2 weeks longer
*Regimen D: Ceftriaxone at 2 g IV or IM daily for 4 weeks
*Regimen E: Vancomycin at 15 mg/kg IV q12h for 4 weeks
Relatively penicillin G resistant (MIC >0.1 μg/mL but <0.5 μg/mL)
Regimen C
*Regimen D or E
Enterococci and viridans streptococci (MIC ≥0.5 μg/mL)
Regimen F: Penicillin G 18-30 million U/d or ampicillin at 12 g/d IV in divided doses q4h, plus gentamicin at 1 mg/kg IV q8h or streptomycin at 7.5 mg/kg IM q12h, both for 4 to 6 weeks
*Regimen G: Vancomycin at 15 mg/kg IV q12h plus gentamicin or streptomycin as in regimen F, both for 4 to 6 weeks
Prosthetic valve (see text)
Staphylococci
Native valve
Methicillin susceptible (Staphylococcus epidermidis, Staphylococcus aureus)
Regimen H: Nafcillin at 2 g IV q4h for 4 to 6 weeks with or without gentamicin 1 mg/kg IV q8h for the first 3 to 5 days
*Regimen I: Cefazolin at 2 g IV q8h for 4 to 6 weeks with or without gentamicin as in regimen H
Regimen J: Vancomycin at 15 mg/kg IV q12h for 4 to 6 weeks
Methicillin resistant
Regimen J
Prosthetic valve
Methicillin susceptible
Regimen H, I, or J: for 6 to 8 weeks with gentamicin for the first 2 weeks and rifampin at 300 mg orally q8h for 6 to 8 weeks
Methicillin resistant
Regimen J: for 6 to 8 weeks with gentamicin for the first 2 weeks and rifampin at 300 mg orally q8h for 6 to 8 weeks

*Regimens for patients allergic to penicillin.
MIC, minimal inhibitory concentration.
From Gorbach SL: Infectious Diseases, 2nd ed. Philadelphia, WB Saunders, 1998.
BOX 8-3 Indications for Cardiac Surgery in Patients with Infective Endocarditis
Indications*
Moderate to severe congestive heart due to valve dysfunction
Partially dehisced unstable prosthetic valve
Persistent bacteremia in the face of optimal antimicrobial therapy
Absence of effective bactericidal therapy
Fungal endocarditis
Relapse of PVE after optimal antimicrobial therapy
Persistent unexplained fever (≥10 days) in patient with culture-negative PVE
Staphylococcus aureus PVE
Staphylococcus epidermidis PVE
Relative Indication†
Perivalvular extension of infection (myocardial, septal, or annulus abscess, intracardiac fistula)
Poorly responsive Staphylococcus aureus endocarditis involving the aortic or mitral valve
Relapse of native valve IE after optimal antimicrobial therapy
Large (>10 mm diameter) hypermobile vegetations
Persistent unexplained fever (≥10 days) in patient with culture-negative native valve IE
Endocarditis due to highly antibiotic-resistant enterococci or gram-negative bacilli

8.13 Acquired Immunodeficiency Syndrome
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Old 06-29-2011
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miss patho can you be specific i can't even read all this

my question is when to give prophylaxis or when to not give

i don't need to know criteria of diagnosis of IE

life is simple ....
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Quote:
Originally Posted by kemoo View Post
miss patho can you be specific i can't even read all this

my question is when to give prophylaxis or when to not give

i don't need to know criteria of diagnosis of IE

life is simple ....
read mtb page 32
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Quote:
Originally Posted by kemoo View Post
miss patho can you be specific i can't even read all this

my question is when to give prophylaxis or when to not give

i don't need to know criteria of diagnosis of IE

life is simple ....

You give prophylaxis in all patient who had endocarditis previously, a unrepaired cyanotic cardiac defect, a prosthetic valve, or a cardiac transplant.

AND

There is a risk of bacteremia such as dental work and respiratory tract surgery. Endoscopy, Colonoscopy, urological procedures are NOT considered into this criteria.

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prophylaxis for Infective endocarditis, need simple explanation

Kemoo, check this out
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