The question continues to confuse many clinicians
By Dianne Glasscoe Watterson, RDH, BS, MBA
The question of whether or not to premedicate patients who have certain heart conditions or joint replacements with antibiotics prior to dental treatment is a perplexing issue today for dental professionals. Unfortunately, there is a lack of clear consensus among physicians concerning the need for premedication, while the specter of antibiotic resistance grows worse every day.
When antibiotics were discovered in 1928, the researcher Alexander Fleming had no idea that what he had stumbled upon would save untold numbers of people from dying untimely deaths from bacterial infections. He found that mold growing on an agar plate had antiseptic properties and actually killed bacteria through interfering with bacterial cell growth. However, it was Australian-born Howard Florey and Ernst Chain, a Jewish refugee from Berlin, who proved its efficacy and delivered penicillin to humanity.
The first antibiotics were prescribed in the late 1930s, and bacterial infection as a cause of death plummeted. In fact, between 1944 and 1972 human life expectancy jumped by eight years -- an increase largely credited to the introduction of antibiotics. Experts were confident that the war had been won over bacterial infections. Penicillin was nicknamed "the wonder drug," and in 1945, Fleming, Chain, and Florey were awarded the Nobel Prize for Medicine.
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However, not everyone in the research community was so convinced, and many were uncomfortable with these predictions, including Alexander Fleming, who wrote:
"The greatest possibility of evil in self-medication is the use of too-small doses so that instead of clearing up infection the microbes are educated to resist penicillin and a host of penicillin-fast organisms is bred out which can be passed to other individuals and from them to others until they reach someone who gets a septicemia or pneumonia which penicillin cannot save." (New York Times, June 26, 1945)
Early signs of resistance
As early as four years after the discovery of antibiotics, there were signs of resistance. However, all through the 1950s and 1960s, several new antibiotics were developed, and resistance did not seem to be an important issue. Between 1940 and 1962, there were 20 classes of antibiotics introduced to the market. Since 1962, there have been only two new antibiotic classes developed.
In the early 1970s, several new resistant strains of pneumonia and venereal diseases had emerged. Drug companies were no longer developing new antibiotics, but rather were focusing their research and development resources on viral infections and antihypertensive and cholesterol-lowering medications.
The emergence of antibiotic-resistant pathogens is an alarming reality today. In the United States alone, hospital-acquired infections afflict nearly two million patients and kill more than 90,000 people annually. This is more than diabetes or influenza/pneumonia-related deaths and more than twice the number of people killed in auto accidents. Further, about 70% of hospital-acquired infections are resistant to at least one drug. Nosocomial (hospital-acquired) infections cost the United States society between $4 billion and $5 billion annually.
For some infections, we do not have any effective antibiotic agents. According to the director of the CDC, Thomas R. Frieden, MD, MPH, the problem of antibiotic resistance is catastrophic. In a recent Medscape interview, Dr. Frieden stated, "We need a balanced portfolio. We need to track where antibiotic resistance is happening. We need to stop it where it is happening. We need to improve antimicrobial stewardship, and we need new antibiotics. Antimicrobial stewardship is very important. We estimate that about half of all the antibiotics used in this country are either unnecessary or inappropriate. Those are antibiotics used in people in this country. And so there is a lot more that we can do to make sure that people get the right antibiotics at the right time that will protect patients and that will preserve the antibiotics for the future, but we need that balanced portfolio of tracking, prevention, stewardship, and research on new drugs."
Several resistant organisms have been identified and include:
- Methicillin-resistant staphylococcus aureus (MRSA). MRSA is an antibiotic-resistant bacterium that fights off the body's immune system and destroys tissues. The community-associated variety, seen in tattoo infections, has been diagnosed in otherwise healthy athletes, military recruits, and prison inmates. The skin infections can be transmitted from person to person by contact with draining sores or through contact with contaminated items or surfaces. MRSA generally causes mild skin infections, but in some cases has led to pneumonia, bloodstream infections, and a painful, flesh-destroying condition called necrotizing fasciitis.
- C-difficile. C-difficile is an intestinal pathogen that causes intestinal ulceration.
- Acinetobacter. Infectious and frequently drug-resistant, this bug is carried harmlessly on at least a quarter of all healthy people's skin. But when transmitted to weakened hospitalized patients, it can prove deadly.
- Pseudomonas aeruginosa. Sometimes found in poorly maintained hot tubs and swimming pools, this bug can cause severe infections of the bloodstream (bacteremia).
- Klebsiella. Normally found in the large bowel, this bug has been known to cause pneumonia and other infections when transmitted to hospitalized patients.
- Carbapenem-resistant Enterobacteriaceae (CRE). This emerging pathogen is responsible for up to 50% mortality in afflicted individuals.
- Drug-resistant gonorrhea.
The current trend
In response to the alarming increase in antibiotic resistance, two important agencies have responded with updated guidelines for dental professionals regarding antibiotic premedication. The AHA guidelines seem straightforward, while the AAOS guidelines are less clear.
The American Heart Association Guidelines -- In April 2007, the American Heart Association published updated premedication guidelines related to dental procedures and at-risk patients. The committee reported that premedication with antibiotics prior to dental care is not supported by the evidence. As it turned out, they found zero evidence that preventive antibiotics benefitted patients in preventing endocarditis. The consensus was this: Dental procedures do not increase the risk of endocarditis for at-risk patients, as many events of everyday living can cause bacteremia, such as defecation, skin abrasions, tooth brushing, flossing, and using a toothpick. In light of this knowledge, premedication with antibiotics for most patients with heart conditions is not warranted.
However, the committee did not discontinue premedication across the board. There are a few extremely high risk or immunocompromised patients for whom premedication is still indicated.
Here is a summary of conditions for which premedication is indicated:
- Artificial heart valves.
- A history of an infection of the lining of the heart or heart valves known as infective endocarditis.
- A heart transplant in which a problem develops with one of the valves inside the heart.
- Heart conditions that are present from birth, such as:
>> Unrepaired cyanotic congenital heart disease, including people with palliative shunts and conduit.
>> Defects repaired with a prosthetic material or device -- whether placed by surgery or catheter intervention -- during the first six months after repair.
>> Cases in which a heart defect has been repaired, but a residual defect remains at the site or adjacent to the site of the prosthetic patch or prosthetic device used for the repair.
The American Academy of Orthopedic Surgeons Guidelines (AAOS) -- In December 2012, the AAOS and the ADA published that there is insufficient evidence to recommend the routine use of antibiotics for patients with orthopedic implants to prevent infections prior to having dental procedures, because there is no direct evidence that routine dental procedures can cause prosthetic joint infections. The guideline was based primarily on clinical research that examined a large group of patients, all having a prosthetic hip or knee and half with an infected prosthetic joint. The research showed that invasive dental procedures, with or without antibiotics, did not increase the odds of developing a prosthetic joint infection.
The summary of the recommendations (which can be viewed at www.aaos.org) is based on a systematic review of the correlation between dental procedures and prosthetic joint infection. It states:
Recommendation one, which is based on limited evidence, supports that practitioners consider changing their longstanding practice of prescribing prophylactic antibiotics for patients who undergo dental procedures. Limited evidence shows that dental procedures are unrelated to prosthetic joint infection (PJI).
Recommendation two addresses the use of oral topical antimicrobials (topical antibiotic administered by a dentist) in the prevention of PJI in patients undergoing dental procedures. There is no direct evidence that the use of oral topical antimicrobials before dental procedures will prevent PJI.
Recommendation three is the only consensus recommendation in the guideline, and it supports the maintenance of good oral hygiene.
The threat of antibiotic reactions
Another real danger for anyone taking an antibiotic is the possibility of an untoward antibiotic reaction. People who have taken many antibiotics throughout their lifetimes are at risk for experiencing a sensitizing dose the leads the individual into an allergic reaction. Reactions can range from mild to severe. Mild reactions include an itchy skin rash or hives. More serious reactions can include toxic epidermal necrolysis, which is characterized by skin blistering and peeling and sometimes accompanied by fever, cough, tiredness, or breathing, vision, or digestive system disturbances; angioedema, which is swelling of the tissues of the body, including lips, tongue, and eyelids; breathing difficulty; or anaphylaxis, a sudden, life-threatening allergic reaction with severe symptoms including skin rash, tingling in the mouth, trouble breathing, tightness in the throat, fast heartbeat, fainting, and possibly nausea and vomiting.
In the past, the problems of antibiotic resistance and reactions were not considered to be a threat to public safety, and dental professionals and physicians felt the benefits of premedication outweighed the risks. Over the past five to 10 years, there has been a dramatic shift in thinking on this issue. Every year, the number of deaths related to antibiotic-resistant pathogens increases. New antibiotic research is not keeping pace with the ever-growing problem, and we now have a number of diseases for which we have no effective antibiotics. While antibiotics are useful adjuncts for treating dental infections, premedication antibiotics may not be warranted. Dental professionals should consult a patient's physician if there is any question as to whether premedication is indicated. Further, it is prudent to request that the patient's physician be responsible for prescribing any antibiotics that he or she feels is necessary prior to dental procedures, in light of the lack of evidence supporting premedication antibiotics for preventing joint infections and certain heart conditions.
DIANNE GLASSCOE WATTERSON, RDH, BS, MBA, is a professional speaker, writer, and consultant to dental practices across the United States. Dianne's new book, "The Consummate Dental Hygienist: Solutions for Challenging Workplace Issues," is now available on her website. To contact her for speaking or consulting, call (301) 874-5240 or email [email protected]. Visit her website at www.professionaldentalmgmt.com.