Subacute bacterial endocarditis (SBE) is the microbial infection of the endocardium with an indolent nature. It has the potential to disseminate by means of septic emboli.
Presentation
Although subacute bacterial endocarditis (SBE) develops insidiously and has a slow progression over weeks to months, it is often aggressive. Usually, no evident portal of entry or source of infection can be found. The most common causative microorganism is streptococci (especially viridans, anaerobic, enterococci, microaerophilic, and non-enterococcal group D streptococci). SBE is less commonly caused by staphylococcus epidermidis and staphylococcus aureus. SBE is generally developed on abnormal valves after asymptomatic bacteremia resulting from gastrointestinal, genitourinary, or periodontal infections.
The initial symptoms are vague, including night sweats, malaise, fatigability, weight loss, anorexia, myalgia, dyspnea, and low-grade fever (< 39°C) [1]. Arthralgias and chills are possible. Valvular insufficiency features may be the first clue. Early in the course of the disease, ≤ 15% of patients have a murmur or fever but all eventually develop both. On physical examination, normal findings can be observed or fever, pallor, tachycardia, and change in a murmur or a new regurgitant type may be detected.
Approximately 35% of cases show CNS effects like transient ischemic attacks, stroke, or brain abscesses and subarachnoid hemorrhage due to mycotic aneurysm rupture. Potential renal emboli can result in flank pain. Splenomegaly and clubbing of fingers and toes may occur because of prolonged infection.
The four peripheral signs of endocarditis include:
- Roth spots: Retinal emboli that appear as oval or round hemorrhagic lesions on the retina with white centers on fundoscopic examination. Roth spots are also found in hypertension, vasculitis, diabetes mellitus, and intracranial hemorrhages [2]. Other ocular manifestations are retinal hemorrhages and infectious vitritis in embolic disease [3].
- Osler nodes: Painful subcutaneous and erythematous nodules on the digits tips. Osler nodes are one of the classic signs in late-phase SBE. However, they can be found in other conditions such as bacteremia, systemic lupus erythematosus, and disseminated gonococcal infection. Adequate intravenous antibiotics can resolve Osler nodes within 3 days [4].
- Janeway lesions: Small, erythematous, non-tender, or hemorrhagic macular lesions. They do not have an immunological origin and are present on the palms and soles [5].
- Splinter hemorrhages: Small vertical blood clots under nails. They can also be observed in scleroderma, systemic lupus erythematosus, rheumatoid arthritis, and trauma [6].
Immune System
- Splenomegaly
Findings compatible with both SBE and marantic endocarditis due to a B-cell lymphoproliferative disorder included an elevated ESR, and splenomegaly. Blood cultures eventually became positive during hospitalization. [ncbi.nlm.nih.gov]
It is characterized by a slow, quiet onset with fever, heart murmur, splenomegaly, and development of clumps of abnormal tissue, called vegetations, around an intracardiac prosthesis or on the cusps of a valve. [medical-dictionary.thefreedictionary.com]
Splenomegaly and clubbing of fingers and toes may occur because of prolonged infection. [symptoma.com]
[…] to microemboli and microabscesses with neutrophilic capillary infiltration ) Osler nodes : painful nodules on pads of the fingers and toes Roth spots : retinal hemorrhages with pale centers Signs of acute renal injury, including hematuria and anuria Splenomegaly [amboss.com]
Entire Body System
- Fever
Fever, anaemia, splenomegaly and positive blood cultures for Gram-negative bacteria were found on admission. The fever resolved with antibiotic therapy on the third hospital day but he then developed hemiplegia and multifocal seizures. [ncbi.nlm.nih.gov]
Early in the course of the disease, ≤ 15% of patients have a murmur or fever but all eventually develop both. [symptoma.com]
Diagnosis Endocarditis is suspected in a patient with a heart murmur and unexplained fever for at least one week, and in an intravenous drug abuser with a fever, even in the absence of hearing a murmur. [healthcentral.com]
- Weight Loss
The diagnosis of subacute bacterial endocarditis (SBE) is suggested by a history of an indolent process characterized by fever, fatigue, anorexia, and unexplained weight loss. [ncbi.nlm.nih.gov]
Long-term fever, weight loss, joint pain and muscle pain, fatigue and anemia. Heart murmur, petechiae, emboli phenomena. Blood culture is positive. [remedyland.com]
The initial symptoms are vague, including night sweats, malaise, fatigability, weight loss, anorexia, myalgia, dyspnea, and low-grade fever (< 39°C). Arthralgias and chills are possible. Valvular insufficiency features may be the first clue. [symptoma.com]
Patients may experience such general symptoms as fevers, chills, fatigue, weight loss, muscle aches, and sweating. These general, nonspecific, symptoms can make it hard both for the patient and the doctor to recognize endocarditis. [diagnose-me.com]
- Chills
Patients may experience such general symptoms as fevers, chills, fatigue, weight loss, muscle aches, and sweating. These general, nonspecific, symptoms can make it hard both for the patient and the doctor to recognize endocarditis. [diagnose-me.com]
Arthralgias and chills are possible. Valvular insufficiency features may be the first clue. Early in the course of the disease, ≤ 15% of patients have a murmur or fever but all eventually develop both. [symptoma.com]
Clinical features include constitutional symptoms (fatigue, fever /chills, malaise ) in combination with signs of pathological cardiac changes (e.g., new or changed heart murmur, heart failure signs) and possibly manifestations of subsequent damage to [amboss.com]
Acute Bacterial Endocarditis Patients with acute or recent infection High temperature with chills, sweating, weakness Sudden changes or appearance of new murmurs The emergence embolism, petechiae and toxic effects General intoxication, an enlarged spleen [remedyland.com]
- Fatigue
The diagnosis of subacute bacterial endocarditis (SBE) is suggested by a history of an indolent process characterized by fever, fatigue, anorexia, and unexplained weight loss. [ncbi.nlm.nih.gov]
Acute bacterial endocarditis usually begins suddenly with a high fever, fast heart rate, fatigue, and rapid and extensive heart valve damage. [merckmanuals.com]
The symptoms of acute IE usually begin with fever (102°–104°F), chills, fast heart rate, fatigue, night sweats, aching joints and muscles, persistent cough or swelling in the feet, legs or abdomen. [heart.org]
- Malaise
Among the signs of subacute bacterial endocarditis are: Malaise Weakness Excessive sweat Fever It is usually caused by a form of Viridans group streptococcus bacteria that normally live in the mouth (Streptococcus mutans, mitis, sanguis or milleri).Other [en.wikipedia.org]
The initial symptoms are vague, including night sweats, malaise, fatigability, weight loss, anorexia, myalgia, dyspnea, and low-grade fever (< 39°C). Arthralgias and chills are possible. Valvular insufficiency features may be the first clue. [symptoma.com]
This form of endocarditis develops rapidly, with fever, malaise, and other signs of systemic infection coupled with abnormal cardiac function and… Read More formation of antigen-antibody complexes In immune system disorder: Type III hypersensitivity … [britannica.com]
Clinical features include constitutional symptoms (fatigue, fever /chills, malaise ) in combination with signs of pathological cardiac changes (e.g., new or changed heart murmur, heart failure signs) and possibly manifestations of subsequent damage to [amboss.com]
[…] and platelets Prognosis often presents as fever of unknown origin endocarditis prophylaxis may be required before dental procedures Presentation Symptoms persistent fevers (the most common symptom) shortness of breath systemic symptoms weakness fever malaise [step1.medbullets.com]
Respiratoric
- Pleural Effusion
[…] thickening, and minimal bilateral pleural effusion (Figure 1 A). [bmcnephrol.biomedcentral.com]
The cardiac silhouette may be enlarged due to pericardial effusion. Some patients may also show pleural effusion. Echocardiography Echocardiography is the primary imaging modality of cardiac infections. [radiopaedia.org]
- Persistent Cough
The symptoms of acute IE usually begin with fever (102°–104°F), chills, fast heart rate, fatigue, night sweats, aching joints and muscles, persistent cough or swelling in the feet, legs or abdomen. [heart.org]
- Clubbed Finger
Obliteration in clubbed fingers of the diamond-shaped window normally produced when the dorsal surfaces of the corresponding finger of each hand are opposed (Schamroth sign) may useful for the identification of clubbing. [40] Complications Since clubbing [emedicine.medscape.com]
Cardiovascular
- Heart Disease
AbP is given to patients with known rheumatic or other valvular heart disease by 98.9% of responders and to patients with known prosthetic heart valves by 81.5%. [ncbi.nlm.nih.gov]
The subacute bacterial endocarditis is usually a rheumatic or congenital heart disease. [remedyland.com]
- Heart Murmur
Clinical manifestations of infective endocarditis is heart murmurs and signs of congestive heart failure. Much less common is heart blockage and pericarditis. [remedyland.com]
Infective endocarditis is a microbial infection of the endocardial surface of the heart. Its symptoms and signs are varied, and include fever, heart murmur, peripheral embolism, and heart failure. [ncbi.nlm.nih.gov]
In addition to the general symptoms of infective endocarditis, there may be a heart murmur from blood flowing backward through a defective valve (regurgitative murmur) or a murmur suggestive of blood outflow obstruction (systolic murmur). [rarediseases.org]
About 90 percent of patients will have heart murmurs, but murmurs may be absent in patients with right-sided heart infections. A changing murmur is common only in acute endocarditis. [healthcentral.com]
- Tachycardia
On physical examination, normal findings can be observed or fever, pallor, tachycardia, and change in a murmur or a new regurgitant type may be detected. [symptoma.com]
Heart murmur is present in approximately 80-90% of patients, and in subacute bacterial endocarditis is more frequent up to 95% and it is accompanied by tachycardia and other signs of aggravated heart failure. [remedyland.com]
There may also be a rapid heartbeat (tachycardia). Individuals with prosthetic valvular endocarditis may develop abscesses on or near the valves. Bacteria may also grow in the heart and obstruct the flow of blood through it. [rarediseases.org]
[…] glomerulonephritis ;, Osler nodes Therapeutic consequences Lack of valve vascularization requires antibiotic treatment for several weeks References: [14] [15] [6] [16] Clinical features Course of disease Constitutional symptoms Fever and chills (∼ 90% of cases), tachycardia [amboss.com]
- Systolic Murmur
In addition to the general symptoms of infective endocarditis, there may be a heart murmur from blood flowing backward through a defective valve (regurgitative murmur) or a murmur suggestive of blood outflow obstruction (systolic murmur). [rarediseases.org]
- Diastolic Murmur
[…] in IV drug users ; and concomitant HIV infection ;, immunosuppressed patients, ; and patients with central venous catheters Aortic valve regurgitation → early diastolic murmur ; loudest at the left sternal border Signs of progressive heart failure [amboss.com]
Jaw & Teeth
- Recent Dental Work
The patient denied recent dental work and was on no medications at that time. On admission, his body temperature was 38°C and pulse was 105 bpm. Abnormal physical findings included bibasal lung crackles and bilateral lower extremity pitting edema. [bmcnephrol.biomedcentral.com]
Eyes
- Retinal Hemorrhage
Roth spots are also found in hypertension, vasculitis, diabetes mellitus, and intracranial hemorrhages. Other ocular manifestations are retinal hemorrhages and infectious vitritis in embolic disease. [symptoma.com]
[…] as the result of multiple microscopic emboli to the retinal circulation causing retinal hemorrhage and a vitreous inflammatory response leading to a mild decrease in VA. [retinalphysician.com]
Infective Endocarditis SIGNS Petechial Hemorrhages Linear Hemorrhages Osler Nodes Janeway Lesions Retinal Hemorrhages Heart Murmur 8. Infective Endocarditis Outcome Fatal 10-70% of cases 9. [slideshare.net]
Skin
- Janeway Lesion
Janeway lesions: Small, erythematous, non-tender, or hemorrhagic macular lesions. They do not have an immunological origin and are present on the palms and soles. Splinter hemorrhages: Small vertical blood clots under nails. [symptoma.com]
A case is reported with splinter hemorrhages and Janeway lesions, resulting from an infected radial artery catheter. [ncbi.nlm.nih.gov]
Janeway lesions are splinter hemorrhages that you see on the fingernails. Osler’s nodes are papular, erythematous lesions found on the palms and soles. [dummies.com]
See also bacterial endocarditis, endocarditis, Janeway lesion. observations The infected vegetations may separate from the valve or prosthesis and form emboli. [medical-dictionary.thefreedictionary.com]
On physical exam, there may be conjunctival hemorrhages, splinter hemorrhages, Janeway lesions (nontender hemorrhagic macules and papules on the palms), Osler nodes (painful erythematous nodules located on the fingertips), or Roth spots (pale lesions [visualdx.com]
- Splinter Hemorrhage
SBE manifests many skin findings including petechiae, splinter hemorrhages of the nails, Osler's and laneway lesions, clubbing of the fingers, and findings suggestive of angiitis. [ncbi.nlm.nih.gov]
Osler's nodes, petechiae, Roth's spots, and splinter hemorrhages under the fingernails are common manifestations of blood-borne metastases of these emboli. [medical-dictionary.thefreedictionary.com]
Janeway lesions: Small, erythematous, non-tender, or hemorrhagic macular lesions. They do not have an immunological origin and are present on the palms and soles. Splinter hemorrhages: Small vertical blood clots under nails. [symptoma.com]
- Petechiae
SBE manifests many skin findings including petechiae, splinter hemorrhages of the nails, Osler's and laneway lesions, clubbing of the fingers, and findings suggestive of angiitis. [ncbi.nlm.nih.gov]
In these cases, the changes are masked and as the first warning sign, suddenly embolism, then petechiae, unexpected heart failure, altered murmur or high temperature can occur. [remedyland.com]
Osler's nodes, petechiae, Roth's spots, and splinter hemorrhages under the fingernails are common manifestations of blood-borne metastases of these emboli. [medical-dictionary.thefreedictionary.com]
[…] dehiscence of a prosthetic valve New valvular regurgitation Minor criteria Predisposing cardiac disease Intravenous drug abuse Fever ≥38° C Vascular phenomena: arterial embolism, pulmonary septic embolism, mycotic aneurysm, intracranial hemorrhage, petechiae [symptoma.com]
- Skin Rash
Call your doctor if you have any of these signs of an infection: Fever over 100°F(38.4°C) Sweats or chills, particularly night sweats Skin rash Pain, tenderness, redness or swelling Wound or cut that won't heal Red, warm or draining sore Sore throat, [my.clevelandclinic.org]
Other signs and symptoms include poor appetite, feeling weak or tired, joint pains, skin rashes, and changes in the nature of a previously present heart murmur. [csun.edu]
rash Splinter haemorrhages and conjunctival haemorrhages Oslers nodes – tender nodules on pulps of fingers and toes Janeway lesions – non-tender haemorrhagic pulps on fingers and toes Roth spots – retinal hemorrhages with a pale centre Splenomegaly New [lifeinthefastlane.com]
The diagnosis of acute interstitial nephritis is usually based on the clinical presentation (fever, skin rash, acute arthralgia), and laboratory findings (eosinophilia and abnormal urinalysis findings of eosinophiluria, proteinuria, hematuria, sterile [antimicrobe.org]
- Palpable Purpura
The case of a patient who had palpable purpura on his lower extremities due to Lactobacillus-caused subacute bacterial endocarditis is reported. Histologic examination of the purpuric lesions demonstrated a leukocytoclastic angiitis. [ncbi.nlm.nih.gov]
Palpable purpura may also be seen. Imaging may reveal septic pulmonary infarcts, mycotic aneurysms, and stroke. [visualdx.com]
Physical examination revealed palpable purpura, mild hypertension, hepatosplenomegaly, and a holosystolic cardiac murmur (Levine 2/6). Echocardiography showed tricuspid valve vegetations with moderate to severe regurgitation. [bmcnephrol.biomedcentral.com]
Workup
The diagnosis of endocarditis is challenging since the presentation varies from case to case. The symptoms of SBE can take several weeks or months to develop while some patients show symptoms acutely after a few days [7].
Laboratory studies may show anemia, leukocytosis, elevated erythrocyte sedimentation rate (ESR), and microscopic hematuria. Although, bacterial endocarditis can be present in the absence of these findings [8].
If endocarditis is suspected, three sets of blood cultures (20 mL each) must be obtained from a separate new venipuncture site within 24 hours.
Echocardiography should be performed. Transthoracic echocardiography (TTE) is usually preferred since it is less costly and non-invasive compared to transesophageal echocardiography (TEE).
The definite diagnosis of infective endocarditis is done when microorganisms are cultured or observed histologically after being obtained from endocardial vegetations during embolectomy, cardiac surgery, or autopsy. Since this is not always possible, diagnostic criteria called revised Duke's criteria has been established with a specificity and sensitivity of more than 90%.
For a definite clinical diagnosis: 2 major criteria are needed, or 1 major and 3 minor criteria, or 5 minor criteria.
For a potential clinical diagnosis: 1 major criterion and 1 minor criterion are needed, or 3 minor criteria.
Major criteria
- 2 positive blood cultures for typical microorganisms causing endocarditis
- 3 positive blood cultures for microorganisms that are consistent with endocarditis
- Serologic evidence of Coxiella burnetii infection (or 1 positive blood culture)
- Evidence of endocardial involvement on echocardiography:
- Oscillating intracardiac vegetative mass on a valve, or on the supporting structures, in the path of regurgitant jets, or on implanted material without other anatomic explanation
- Cardiac abscess
- Newly developed dehiscence of a prosthetic valve
- New valvular regurgitation
Minor criteria
- Predisposing cardiac disease
- Intravenous drug abuse
- Fever ≥38° C
- Vascular phenomena: arterial embolism, pulmonary septic embolism, mycotic aneurysm, intracranial hemorrhage, petechiae on the conjunctiva, Janeway lesions
- Immunologic phenomena: glomerulonephritis, Osler nodes, Roth spots, positive rheumatoid factor
- Microbiological evidence of infection that is consistent with but not meeting major criteria
- Serologic evidence of infection with organisms consistent with causing endocarditis
Microbiology
- Blood Culture Positive
Diagnosis 5.1 Clinical features 5.2 Laboratory findings 5.3 Imaging techniques 5.3.1 Echocardiography 5.3.2 Multislice computed tomography 5.3.3 Magnetic resonance imaging 5.3.4 Nuclear imaging 5.4 Microbiological diagnosis 5.4.1 Blood culture–positive [escardio.org]
positive for infectious organisms Blood cultures that are positive for microorganisms, which are taken 12 hours apart 3 blood cultures positive on separate occasions that are taken at least 1 hour apart Abnormalities in echocardiogram showing either a [dovemed.com]
[…] with IE Blood cultures persistently positive for one of these organisms, from cultures drawn more than 12 hours apart Three or more separate blood cultures drawn at least 1 hour apart Major echocardiographic criteria include the following: Echocardiogram [emedicine.medscape.com]
Pleura
- Pleural Effusion
[…] thickening, and minimal bilateral pleural effusion (Figure 1 A). [bmcnephrol.biomedcentral.com]
The cardiac silhouette may be enlarged due to pericardial effusion. Some patients may also show pleural effusion. Echocardiography Echocardiography is the primary imaging modality of cardiac infections. [radiopaedia.org]
Treatment
[…] endocarditis. 3 The present report, which deals with the apparently successful treatment of 7 consecutive examples of subacute bacterial endocarditis, employs variations on previous technics. [doi.org]
If a stable patient has suspected IE but is already on antibiotic treatment, consideration should be given to stopping treatment and performing three sets of blood cultures off antibiotics. [patient.info]
The amnesia completely resolved after treatment with intravenous penicillin for subacute bacterial endocarditis secondary to a viridans streptococcus. [ncbi.nlm.nih.gov]
Prognosis
Aortic insufficiency has the hardest prognosis and requires appropriate surgical intervention. Worst prognosis have embolism which affect the brain. [remedyland.com]
Outcome after discharge: follow-up and long-term prognosis 11.1 Recurrences: relapses and reinfections 11.2 Short-term follow-up 11.3 Long-term prognosis 12. [escardio.org]
What is the Prognosis of Bacterial Endocarditis? (Outcomes/Resolutions) Bacterial Endocarditis, if left untreated is almost always fatal. [dovemed.com]
Prognosis and Predictive Factors The overall mortality of infectious endocarditis is approximately 20-25%, and it is increased with advanced patient age, left-sided disease, methicillin-resistant S aureus (MRSA) infection, and chronic renal failure. [emedicine.medscape.com]
Each problem is presented on a two-page spread in boxes with consistent headings including introduction; etiology, pathophysiology and risk factors; patient presentation; differential diagnosis; diagnostic evaluation; treatment and management; and prognosis [books.google.com]
Etiology
Certain conditions have both an underlying etiology and multiple body system manifestations due to the underlying etiology. [icd10coded.com]
Two major types of endocarditis exist: infectious endocarditis, which has a microbial etiology, and noninfectious endocarditis. Mitral valve: endocarditis with large vegetation on the atrial aspect of the valve. [emedicine.medscape.com]
Streptococcus viridans is the usual etiologic agent of sbe. [icd9data.com]
A clear, comprehensive introduction to disease, Pathophysiology, 5th Edition explores the etiology, pathogenesis, clinical manifestations, and treatment of disorders. [books.google.com]
[…] and multiple body system manifestations due to the underlying etiology. [icd10data.com]
Epidemiology
Conventions Publication Fees Ethics Resources and Policies About the Journal About IAI Editor in Chief Editorial Board For Reviewers For the Media For Librarians For Advertisers Alerts RSS FAQ Subscribe Members Institutions Pathogenic Mechanisms, Ecology, and Epidemiology [iai.asm.org]
[…] abscess formation • Mycotic aneurysm: : A term applied to fungal or bacterial infection within the wall of a vessel • Mycotic endocarditis: : Endocarditis caused by fungus Objectives After completing this article, readers should be able to: Discuss the epidemiology [pedsinreview.aappublications.org]
Introduction Clinical definition inflammation of the heart valve, typically secondary to infection Epidemiology location mitral valve > tricuspid valve tricuspid valve disease is associated with intravenous (IV) drug use Staphylococcus aureus, Pseudomonas [step1.medbullets.com]
Infective endocarditis epidemiology over five decades: a systematic review. PLoS One. 2013. 8 (12):e82665. [Medline]. Mendiratta P, Tilford JM, Prodhan P, Cleves MA, Wei JY. [emedicine.medscape.com]
Pathophysiology
[…] clarify complex pathophysiological concepts. [books.google.com]
Management of specific situations 12.1 Prosthetic valve endocarditis 12.1.1 Definition and pathophysiology 12.1.2 Diagnosis 12.1.3 Prognosis and treatment 12.2 Infective endocarditis affecting cardiac implantable electronic devices 12.2.1 Introduction [escardio.org]
Infected peripheral venous catheters, surgery, dental procedures Non-sterile venous injections (e.g., IV drug abuse ) Bacterial infections of various organs (e.g., UTIs, spondylodiscitis ) References: [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] Pathophysiology [amboss.com]
[…] defibrillator, IVDA (right sided endocarditis), indwelling catheter Congenital heart disease: small ventricular septal defect, bicuspid aortic valve, coarctation of aorta, patent ductus arteriosus Uncommon with large VSD, mitral stenosis, atrial septal defect Pathophysiology [pathologyoutlines.com]
Prevention
So, I don’t recommend antibiotic prophylaxis to prevent prosthetic joint infections. [tcmp.med.ubc.ca]
A high suspicion of potential complications can prevent morbidity and mortality. [ncbi.nlm.nih.gov]
To prevent relapse, chemotherapy must eliminate the last surviving organisms from the endocardial focus. [mdedge.com]
References
- Mylonakis E, Calderwood SB. Infective endocarditis in adults. N Engl J Med. 2001;345:1318–30. doi: 10.1056/NEJMra010082.
- Fred HL. Little black bags, ophthalmoscopy, and the Roth spot. Tex Heart Inst J. 2013;40:115–6.
- Habib G, Hoen B, Tornos P, et al. Guidelines on the prevention, diagnosis, and treatment of infective endocarditis (new version 2009): The task force on the prevention, diagnosis, and treatment of Infective Endocarditis of the European society of Cardiology (ESC). Eur Heart J. 2009;30(19):2369-413.
- Jackson TL, Eykyn SJ, Graham EM, Stanford MR. Endogenous bacterial endophthalmitis: a 17-year prospective series and review of 267 reported cases. Surv Ophthalmol. 2003;48:403–23. doi: 10.1016/S0039-6257(03)00054-7.
- Farrior JB, Silverman ME. A consideration of the differences between a Janeway’s lesion and an Osler’s node in infectious endocarditis. Chest. 1976;70:239–43. doi: 10.1378/chest.70.2.239.
- Robertson JC, Braune ML. Splinter haemorrhages, pitting, and other findings in fingernails of healthy adults. Br Med J. 1974;4:279–81. doi: 10.1136/bmj.4.5939.279.
- Luttenberger K, DiNapoli M. Subacute bacterial Endocarditis. J.Nurse Pract. 2011;36(3):31–38. doi:10.1097/01.npr.0000393971.15598.0c.
- Cunha BA, Gill MV, Lazar JM. Acute infective endocarditis. Diagnostic and therapeutic approach. Infect Dis Clin North Am. 1996;10:811–34.