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September 4, 2018

Think you have a penicillin allergy? You might be wrong— and putting your health at risk.

Daily Briefing

    A "surprisingly" high number of people "wrongly think" they're allergic to penicillin—a misunderstanding that a recent study in the British Medical Journal finds can lead to an increased risk of antibiotic-resistant infections, Kate Furbyreports for the Washington Post's "To Your Health."

    Why the high misdiagnosis?

    According to Furby, 10% of the U.S. patient population believe they have a penicillin allergy. Of those, 90% don't actually have an allergy.

    Jonathan Grein, medical director at the Department of Hospital Epidemiology at Cedars Sinai Medical Center in Los Angeles, said part of the problem is that diagnosing the allergy can be difficult. Common symptoms of a penicillin allergy—diarrhea, nausea, and rash—also can occur by chance in people who are taking antibiotics to treat an illness.

    In addition, Paul Sax, clinical director of infectious diseases at Brigham and Women’s Hospital, noted that some patients diagnosed in childhood could grow out of penicillin allergies. As such, Furby reports, adults should get retested every about 10 years.

    Sax recalled a patient who had a life-threatening heart infection that could be safely treated with penicillin. However, the patient's chart indicated he had a penicillin allergy. The medical team discussed the allergy with the patient, and ultimately they determined that—even though the patient became nauseous and developed diarrhea while on penicillin—he did not have an actual allergy.

    The health risks of misdiagnosis

    The BMJ study, which looked at United Kingdom patient medical records over a six-year period, found that treating patients with penicillin alternatives can have significant health risks.

    The study found patients diagnosed with penicillin allergies who were treated with alternatives to penicillin had an almost 70% increased risk of developing methicillin-resistant Staphylococcus aureus (MRSA) infection MRSA and a 26% increase risk of developing Clostridium difficile-related colitis (C. diff.), when compared to patients without such a penicillin allergy.

    Kim Blumenthal, a lead author of the study and assistant professor of medicine at Harvard Medical School, said, "Penicillin-related drugs, that whole class … they're very effective at killing, and they're very targeted. So for some bacteria they're still the best."

    By contrast, other antibiotics used to treat patients with penicillin allergies tend to be broad-spectrum, killing off both good and bad bacteria. In the good bacteria's absence, life-threatening bacteria can sometimes find a foothold, Furby reports.

    Further, the use of broad-spectrum antibiotics can contribute to the evolution of antibiotic-resistant strains. Helen Boucher, director of Tufts Medical Center's infectious diseases fellowship program, who was not involved in the study, said, "Not only is it harmful to the world and the general population ... but it's harmful to the individual patient. So the message to the public is that it could be dangerous to you or me" (Furby, "To Your Health," Washington Post, 8/10).

    Are you leading an evidence-based organization?

    Despite the shift toward broad acceptance of evidence-based practice (EBP) among medical staff, over half of physicians report not actually using guidelines day-to-day when they are available. As a result, organizations continue to see tremendous variation in clinical practice—as well as in costs and outcomes.

    Our infographic outlines four principles you can use to support EBP at your organization, along with action steps to implement each one and pitfalls to avoid along the way.

    Get the Infographic

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