Patient will present as → a 45-year-old female with a long history of a heart murmur with one week of increasing fatigue and low-grade fevers. She had a dental cleaning two weeks ago. She denies any hematuria, neurological symptoms, or changes in the appearance of her hands and fingernails. Her past medical history is otherwise insignificant. On physical exam, her temperature is 38.1 C (100.6 F), heart rate is 92/min, blood pressure is 118/67, and respiratory rate is 16/min. She appears fatigued but in no acute distress. Cardiac auscultation reveals a grade III/VI holosystolic murmur heard best at the cardiac apex in the left lateral decubitus position. Pulmonary, abdominal, and extremity exams are within normal limits. An echocardiogram is performed and is shown here. The patient is admitted and started on empiric IV antibiotics. Three days later, 4/4 blood cultures grow Streptococcus viridans that is highly sensitive to penicillin.
It causes fever, heart murmurs, petechiae, anemia, embolic phenomena, and endocardial vegetations.
- Acute bacterial endocarditis: Infection of normal valves with a virulent organism (S. aureus)
- Subacute bacterial endocarditis: Indolent infection of abnormal valves with less virulent organisms (S. viridans)
- Endocarditis with intravenous drug users - Staph aureus
- Prosthetic valve endocarditis - Staph epidermidis
"Differentiate bacterial endocarditis from acute rheumatic fever which is a multi-system autoimmune response and may also affect the heart and valves - diagnosed by Jones criteria"
Vegetations may result in valvular incompetence or obstruction, myocardial abscess, or mycotic aneurysm.
- Candida is a slow-growing organism. Most common source is a contaminated line. It typically causes large vegetations in endocarditis.
- Large vegetation endocarditis in the early post–valve replacement period (2 months post-surgery) is most likely due to fungus, that is, Candida infection. Amphotericin B is recommended followed by several weeks of antifungals that carry less adverse events.
- HACEK organisms tend to grow on native valves
- Staphylococcus aureus causes smaller vegetations; it is more common in injection drug users
- Streptococcus viridans is the most common cause of endocarditis. It typically occurs as late complication of valve replacement and presents as small vegetations and embolic events.
- Endocarditis can occur at any age. Men are affected about twice as often as women. IV drug abusers and immunocompromised patients are at highest risk.
- Most patients with new murmur or change in existing murmur; signs of heart failure (rales, edema) if valve function compromised
Peripheral stigmata of IE:
- Splinter hemorrhages in fingernail beds
- Osler nodes painful lesions on fleshy portions of extremities
- “Roth spots” retinal hemorrhages
- Janeway lesions (cutaneous evidence of septic emboli)
- Palatal or conjunctival petechiae
- hematuria (due to emboli or glomerulonephritis)
Neurologic findings consistent with CVA, such as visual loss, motors weakness, and aphasia
Modified Duke Criteria for Diagnosis of Infectious Endocarditis
Definite: 2 major criteria, or 1 major and 3 minor criteria, or 5 minor criteria
Possible: 1 major and 1 minor criteria, or 3 minor criteria
- Major clinical criteria
- Positive blood culture: isolation of typical microorganism for IE from 2 separate blood cultures or persistently positive blood culture
- Single positive blood culture for C. burnetii or antiphase-1 IgG antibody titer >1:800
- Positive echocardiogram: presence of vegetation, abscess, or new partial dehiscence of prosthetic valve; must be performed rapidly if IE is suspected
- New valvular regurgitation (change in preexisting murmur not sufficient)
- Minor criteria
- Predisposing heart condition or IV drug use
- Fever ≥38.0°C (100.4°F)
- Vascular phenomena: major arterial emboli, septic pulmonary infarcts, mycotic aneurysm, intracranial hemorrhage, conjunctival hemorrhage, Janeway lesions
- Immunologic phenomena: glomerulonephritis, Osler nodes, Roth spots, rheumatoid factor (RF) Microbiologic evidence: positive blood culture, but not a major criterion (excluding single positive cultures for coagulase-negative staphylococci and organisms that do not cause endocarditis) or serologic evidence of infection likely to cause IE
Diagnosis requires demonstration of microorganisms in blood and usually echocardiography
- Blood cultures (before antibiotics are started) 3 sets at least 1 hour apart
- EKG at regular intervals
Transesophageal echocardiogram is Gold Standard
LABS: CBC, ESR, RF
Management - treatment consists of prolonged antimicrobial treatment and sometimes surgery
- IV antibiotics (based on the organism and its susceptibility)
- Sometimes valve debridement, repair, or replacement
- Initial therapy before organism identification (but after adequate blood cultures have been obtained) should be broad spectrum to cover all likely organisms.
- Typically, patients with native valves and no IV drug abuse receive ampicillin 500 mg/h continuous IV infusion plus nafcillin 2 g IV q 4 h plus gentamicin 1 mg/kg IV q 8 h.
- Patients with a prosthetic valve receive vancomycin 15 mg/kg IV q 12 h plus gentamicin 1 mg/kg q 8 h plus rifampin 300 po q 8 h.
- IV drug abusers receive nafcillin 2 g IV q 4 h.
- In all regimens, penicillin-allergic patients require substitution of vancomycin 15 mg/kg IV q 12 h.
Antibiotic prophylaxis to prevent recurrent endocarditis is recommended : 2 g of Amoxicillin 30-60 minutes before procedure
|Bacterial endocarditis is an infection of the inner surface of the heart or heart valves due to bacteria in the bloodstream, typically introduced via dental or medical procedures in the mouth, intestinal tract or urinary tract. The bacteria can grow on the edges of a heart defect or surface of an abnormal valve and continue to grow producing large particles called vegetations. These particles can then break off and embolize to the lungs, brain, kidneys, and skin. Symptoms and signs of endocarditis vary but include prolonged fever, a new or changing heart murmur and specific vascular and immunologic phenomena. Vascular phenomena include septic emboli, Janeway lesions, splinter hemorrhages and renal and splenic infarcts. Immunologic phenomena include Osler’s nodes and Roth’s spots.|
|The Duke criteria are a set of clinical criteria set forward for the diagnosis of infective endocarditis. Fulfilling the criteria includes either having 2 major criteria, 1 major and 3 minor criteria, or 5 minor criteria. The two major criteria are positive blood cultures for infective endocarditis and evidence of endocardial involvement. The five minor criteria are having a predisposing heart condition or intravenous drug use, fever, vascular phenomena, or having microbiologic evidence or echocardiographic evidence that does not meet the major criteria.|
This patient does not require antibiotic prophylaxis for a routine dental cleaning.
This should receive Pen VK 250 mg p.o. QID for 10 days after the procedure.
This patient should receive Amoxicillin 2 grams 30-60 minutes before the procedure
This patient should receive Erythromycin 250 mg QID for 1 day before the procedure and then 10 days after the procedure.
See B for explanation.
Systemic arterial embolization of vegetation
Hypotension and tachycardia
See B for explanation.
Activation of the immune system
Glomerulonephritis and arthritis result from activation of the immune system.
Acute myocardial infarction
Acute MI presents with complaint of chest pain, SOB, not with fever and myalgias.
Pericarditis does not present with systolic or diastolic murmur or vegetation, more commonly pericardial friction rub would be noted.
Restrictive cardiomyopathy will show impaired diastolic filling on echocardiogram and is not associated with fever.
Bicuspid aortic valve
Prosthetic heart valve
Congenital heart disease
History of endocarditis
Amoxicillin 2g 30-60 minutes before the procedure
Amoxicillin 1g 30-60 minutes before the procedure
Amoxicillin 2g three hours before the procedure
Clindamycin 600 mg 30-60 minutes before the procedure
Fever greater than 100.4
Sustained bacteremia (2 + blood cultures by organism known to cause endocarditis)
Predisposing condition (abnormal valves, IVDA, indwelling catheters)
Immunologic phenomena: Osler's nodes, Roth spots
Vascular and Embolic phenomena: Janeway lesions, pulmonary emboli
HACEK organisms tend to grow on native valves.
Staphylococcus causes smaller vegetations; it is more common in injection drug users.
Streptococcus viridans is the most common cause of endocarditis. It typically occurs as late complication of valve replacement and presents as small vegetations and embolic events.