Infective Endocarditis

Signs and Symptoms

Infective endocarditis is an infection of the heart -- either the lining, called the endocardium, or the valves -- caused by bacteria. It is normal for bacteria in the mouth, intestinal tract or urinary tract to travel to the heart via the bloodstream and this usually does not cause a problem. However, hearts that have defects, often even if the defects have been repaired, are vulnerable to infection. Once infection occurs, the bacteria continue to grow and may seriously damage the heart.

A number of preexisting conditions increase a child's risk of developing endocarditis, including:

• Congenital heart disease, such as aortic coarctation, Tetralogy of Fallot and transposition of the great arteries
• Rheumatic heart disease
• Cardiac valve anomalies

The usual signs of endocarditis are prolonged fever for several days (occasionally up to 30 days) in a child with congenital heart disease that occurs after a procedure in the mouth, intestinal tract or urinary tract. However, the infection may occur without a previous procedure.

Symptoms of endocarditis may either develop slowly or come on suddenly. These include:

• Fatigue
• Fever
• Headache
• Joint inflammation or pain
• Night sweats
• Poor appetite and/or weight loss
• Rash

Signs of endocarditis may include the following:

• Anemia
• An enlarged spleen
• Bleeding that causes small dark lines under the fingernails or small dark spots on the skin
• New heart murmurs

Prevention

The risk of infective endocarditis can be decreased if your child takes antibiotics immediately before procedures in which bacteria may be released into the bloodstream, such as:

• Dental work (any kind)
• Tonsillectomy and adenoidectomy
• Bronchoscopy
• Some surgeries in the respiratory passageways, or the gastrointestinal or urinary tracts
• Gallbladder or prostate surgery

Although many bacteria can cause endocarditis, one type that lives in the mouth, called Streptococcus viridans, is responsible for half of all cases, which is why dental procedures are the most common cause of endocarditis. Therefore children with congenital heart disease should take antibiotics before undergoing dental procedures.

However, this should not be misinterpreted to mean that children with preexisting conditions that put them at risk for endocarditis should not go to the dentist. It is important that these children practice good oral hygiene and see a dentist regularly to ensure their teeth and gums stay healthy, for this is the first step in reducing the need for procedures where bacteria could be released into the bloodstream.

Diagnosis

Since infective endocarditis is associated with preexisting heart conditions, your child's doctor will go over his or her medical history and perform a physical examination. The doctor will check for an enlarged spleen, listen for a new or changing heart murmur, look at the nails and examine the eyes.

Blood tests are key in diagnosing endocarditis and may be run to check the erythrocyte sedimentation rate (ESR), complete blood count and multiple blood cultures to detect the bacteria. Depending on the way the illness presents, tests to exclude other diseases may be performed. In addition, your child's doctor may order the following tests:

• Echocardiogram to assess damage to the heart and large blood vessels.

• Chest X-ray to check the size of the heart and look for signs of heart failure.

• Computerized tomography (CT) scan, which provides a three-dimensional image of the heart.

Treatment

Infective endocarditis is treated with antibiotics that are initially administered intravenously, or through an IV, while your child is in the hospital. Depending on the severity of the infection, your child may need to stay in the hospital for up to six weeks. The antibiotics given to your child will be determined by the bacteria that caused the infection.

Early treatment is usually successful. However, with infective endocarditis it is possible for heart failure to develop, and this risk increases the longer treatment is delayed. If heart failure occurs, your child may need surgery to repair or replace the affected heart valve. If the diagnosis is delayed and severe heart damage has occurred, the child may die.

There also are a number of other complications that, although rare, can occur as a result of endocarditis, such as the development of blood clots, aneurysms, arrhythmia and jaundice.