Preventive administration of antibiotics in endocarditis prophylaxis is intended to prevent bacteria from settling in the heart after dental and other procedures. Today, endocarditis prophylaxis is recommended only for high-risk patients.
What is endocarditis prophylaxis?
Endocarditis prophylaxis is usually recommended for surgical or endoscopic procedures. This primarily includes dental procedures that involve injury to the gums. Endocarditis prophylaxis is intended to prevent endocarditis. It is usually recommended during surgical or endoscopic procedures. These include, in particular, dental procedures that involve injury to the gums. Tooth extractions, root canal treatments and dental scaling are thus indications for endocarditis prophylaxis. Other medical procedures on the upper respiratory tract are also among the indications. In the past, endocarditis prophylaxis was recommended for many other procedures. However, the indications have been increasingly restricted in recent years. The restriction of indications and the associated guidelines have been controversial. There is no clearly documented benefit for endocarditis prophylaxis. However, physicians are still free to use endocarditis prophylaxis after a thorough risk-benefit assessment.
Function, Effect, and Objectives
Endocarditis is an inflammation of the inner lining of the heart. The endocardium lines the heart cavities and forms the heart valves. The causative germs of endocarditis include bacteria from the so-called HACEK group. Germs of this group are Aggregatibacter aphrophilus, Aggregatibacter actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens and Kingella kingae. The natural habitat of these bacteria is the oral cavity. During surgery in this area, they can enter the wound and travel through the bloodstream to the heart. Enterococci, staphylococci, streptococci and Brucella melitensis can also cause endocarditis. Endocarditis is accompanied by fever in 90 percent of cases. Affected individuals are also weak, have little appetite and lose weight. Heart murmurs and signs of heart failure may occur. Petechiae or Osler nodules become visible in 30 percent of cases. Endocarditis can damage the heart valves. Inflammatory plaques can detach from the heart and travel through the bloodstream to the organs. This can lead to pulmonary embolism, cerebral stroke or renal embolism. The spread of germs to other organs with subsequent abscess formation is also possible. In uncomplicated cases, patients are given the antibiotic amoxicillin orally one hour before the procedure for endocarditis prophylaxis. Amoxicillin is an antibiotic from the active group of aminopenicillins. The antibiotic is effective against gram-positive and gram-negative cocci. Escherichia coli, Listeria, Proteus species, and enterococci are also included in the spectrum of activity of amoxicillin. The American Medical Association recommends 2 grams for adults. Dosage for children should be 50 milligrams per kilogram of body weight. If the antibiotic cannot be given orally, the physician may administer the drug intravenously. Ampicillin is also used for this purpose in dental procedures. Ampicillin is also administered during ENT procedures or during surgery of the respiratory tract and esophagus. In addition to ampicillin i.v., gentamycin i.v. is also used for interventions on the intestines, bile ducts or urogenital tract. If the patient is allergic to penicillins and penicillin derivatives, oral administration of azithromycin, linezolid, cephalosporins, clindamycin, and clarithromycin may be substituted. Alternatively, vancomycin may be administered intravenously. Endocarditis prophylaxis is recommended during dental procedures and medical procedures involving the mouth, throat, pharynx, and teeth. These include tooth extractions, root canals, tonsil removals, lymph node removals, polypectomies, and dental scaling. Prophylaxis during procedures on the respiratory tract, gastrointestinal tract or urogenital tract is now only performed in cases of pre-existing infections or if a focus of inflammation is opened during the procedures. Such sites of inflammation are, for example, abscesses or boils.Endocarditis prophylaxis is no longer recommended for esophagogastroduodenoscopies, colonoscopies, bronchoscopies, and endoscopic retrograde cholangiopancreatography. There is an increased risk of infective endocarditis in people with prosthetic heart valves or valvular defects. Congenital heart defects and previous heart transplants also increase the risk of endocarditis. The same is true for previous endocarditis or frequent venous puncture (e.g., dialysis or intravenous drug abuse). The American Heart Association (AHA) recommends endocarditis prophylaxis in high-risk patients with prosthetic heart valves, with congenital heart defects, with previous heart transplantation or valvulopathy, and after surviving endocarditis. The German Society of Cardiology (DGK) largely agrees with these recommendations but recommends prophylaxis for all valvular defects and not exclusively for congenital valvular defects.
Risks, side effects, and hazards
Many patients are allergic to amoxicillin. About one in 7000 patients reacts to its administration with severe allergic symptoms. Symptoms of allergy to amoxicillin range from mild redness of the skin to anaphylactic shock. Penicillins such as amoxicillin also kill beneficial bacteria in the intestinal flora. This can cause diarrhea or other digestive problems. If harmful microorganisms spread in the intestines during antibiotic treatment, antibiotic-associated colitis may develop. This is an inflammation of the colon accompanied by severe pain and diarrhea. Drug fever also occasionally occurs when amoxicillin is administered. Diarrhea, vomiting, and nausea must also be expected. Rarely, patients suffer from sleep disturbances, symptoms of fatigue or confusion. Those who want to or have to do without antibiotics for prophylaxis should give special importance to dental hygiene and dental rehabilitation. Good dental hygiene can reduce the bacterial load in the mouth and thus also prevent endocarditis.