Acute bacterial endocarditis patients are usually severely ill, with high fever, chills, poor appetite, weight loss and possible signs of embolism, acute heart failure or heart block. These may be patients who have previously been diagnosed with a congenital heart disease, individuals who recently underwent various procedures that can cause bacteremia or in whom bacteremia is the primary source. Fever may be absent in elderly or immunocompromised patients [1].

Clinical examination must be carefully performed and special attention must be paid to new murmurs or to a change in character of preexisting murmurs, suggestive of valvular dysfunction [2]. However, murmurs are absent in about 33% of acute bacterial endocarditis cases. Heart rate evaluation is also important because intramyocardial abscesses, especially those originating from the aortic valve [3], can involve the conduction system and cause heart block [4]. The patient may also exhibit acute heart failure symptoms [5], as well as signs of peripheral embolic phenomena, located in the central nervous system, lungs, kidneys, liver and spleen [6] Anterior mitral leaflet vegetations, especially if large and friable, are most likely to embolize [7], but the risk decreases after antibiotic treatment begins. Pulmonary embolism presents with chest pain, acute dyspnea and cough.

Peripheral signs of acute bacterial endocarditis are represented by Janeway lesions, located on the palms and soles and caused by vasculitis. The patient may also have articular or osseous pain, due to septic arthritis or osteomyelitis (most often vertebral). If consciousness level is decreased, the physician should suspect acute stroke or meningitis, that is usually purulent in acute endocarditis [8]. If an implantable device is present, it requires special attention [9]. Macroscopic hematuria may signify the presence of glomerulonephritis or embolic renal infarction.

While evaluating an acute bacterial endocarditis patient, all efforts should be made to identify the etiological agent. A minimum of three blood cultures should be obtained, preferably while the patient is febrile. Blood workup should also include determination of the inflammatory markers and rheumatoid factor. Leukocytosis is usually present. Baseline workup should also include creatinine, urea, blood urea nitrogen, glycemia, and electrolytes.,

The electrocardiogram is able to highlight rhythm and conduction abnormalities if present. The chest radiography is used to mark out concomitant pulmonary infection or pulmonary embolic pyogenic abscesses.

The definitive diagnosis is established following echocardiography, both transthoracic and transesophageal if needed [5]. Emphysema, obesity and valve prosthesis make transthoracic diagnosis more difficult [10]. A vegetation is described as an oscillating mass, usually attached to a valve, but may also be appended to implanted material or ventricular wall. This method is able to describe the size, motility, and consequences of the pathological process, such as leaflet perforation or pillar rupture, dehiscence of a prosthetic valve [11], abscess [12], aneurysm or fistula formation [13].

Computer tomography and magnetic resonance imaging are adjunct methods for acute bacterial endocarditis diagnosis, not widely used in clinical practice, except for selected cases [14].

Urinalysis may demonstrate the presence of hematuria, indicative for immunologically mediated glomerulonephritis or renal infarction. Proteinuria may also be present.

Treatment of Acute Bacterial Endocarditis requires aggressive antibiotic therapy tailored to the specific bacteria identified in blood cultures. Intravenous antibiotics are typically administered for several weeks. In some cases, surgical intervention may be necessary to repair or replace damaged heart valves, especially if there is significant valve dysfunction or persistent infection despite antibiotic treatment.

The prognosis for patients with ABE depends on several factors, including the causative organism, the patient's overall health, and the timeliness of treatment. With prompt and appropriate therapy, many patients can recover fully. However, complications such as heart failure, stroke, or recurrent infection can occur, affecting the long-term outcome. Early diagnosis and treatment are critical for improving prognosis.

Acute Bacterial Endocarditis is primarily caused by bacteria entering the bloodstream and adhering to the heart's endocardium. Common bacteria include Staphylococcus aureus, Streptococcus species, and Enterococcus. Risk factors for developing ABE include pre-existing heart conditions, intravenous drug use, recent dental or surgical procedures, and the presence of prosthetic heart valves.

ABE is a relatively rare condition, with an incidence of approximately 3 to 10 cases per 100,000 people annually. It can affect individuals of any age but is more common in older adults and those with underlying heart conditions. The incidence of ABE has been increasing due to factors such as aging populations, increased use of invasive medical procedures, and rising rates of intravenous drug use.

The pathophysiology of ABE involves the colonization of the heart's endocardium by bacteria. Once bacteria enter the bloodstream, they can adhere to damaged or abnormal heart valves, forming vegetations. These vegetations consist of bacteria, fibrin, and platelets, and can lead to valve destruction, impaired cardiac function, and embolization to other organs, causing systemic complications.

Preventing ABE involves minimizing risk factors and maintaining good health practices. For individuals with known heart conditions, prophylactic antibiotics may be recommended before certain dental or surgical procedures to prevent bacterial entry into the bloodstream. Good oral hygiene and regular dental check-ups are also important in reducing the risk of infection.

Acute Bacterial Endocarditis is a life-threatening infection of the heart's inner lining, requiring immediate medical attention. It presents with symptoms such as fever, heart murmur, and fatigue. Diagnosis involves blood cultures and echocardiography, while treatment includes antibiotics and possibly surgery. Early intervention is crucial for a favorable outcome, and prevention focuses on reducing risk factors and maintaining good health practices.

If you suspect you have symptoms of Acute Bacterial Endocarditis, it is important to seek medical evaluation promptly. Symptoms like fever, fatigue, and changes in heart sounds should not be ignored. Treatment typically involves antibiotics and may require hospitalization. Understanding your risk factors, such as heart conditions or recent medical procedures, can help in early detection and prevention of this serious condition.

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