Becker's Clinical Quality & Infection Control

14 ANTIBIOTIC RESISTANCE & STEWARDSHIP How detecting false penicillin allergies helps physicians fight antibiotic resistance By Megan Knowles M ore than 32 million U.S. patients have a docu- mented penicillin allergy, but studies have found more than 95 percent can be treated safely with this class of antibiotics. Providers can use several practices to verify a documented penicillin allergy and avoid spreading drug resistance, researchers reported in JAMA. e study comes from a consensus development of the American Academy of Allergy, Asthma and Immunolo- gy; the Infectious Diseases Society of America, and the Society for Healthcare Epidemiology of America. The common use of penicillin and related antibi- otics, called beta-lactams, is behind the frequent documentation of penicillin allergy, said lead author Erica Shenoy, MD, PhD. "Many reported penicillin allergies are established during childhood, when it is by far the most commonly prescribed antibiotic. If a penicillin is prescribed for what is actually a viral rather than a bacterial infection, a rash that develops may be caused by the virus but at- tributed to a penicillin allergy, which then is document- ed in the patient's chart and never questioned again," Dr. Shenoy said. When alternatives are used, it can lead to increased risk of treatment or prevention failure, as well as increased risk of resistant pathogens such as Clostridium difficile. To ensure penicillin allergies are properly evaluated and managed, the researchers suggest providers take a comprehensive history of the reaction that led to allergy documentation, which can help identify the patient's risk level and appropriate procedures for testing. "A simple history can oen distinguish intolerances — for example, headaches or nausea — from allergies," said senior author Kimberly Blumenthal, MD. "Side effects should be judged by their severity, and aer discussion with the patient, clinicians should consider the safety of a potential drug challenge." e study authors said some form of evaluation of a docu- mented penicillin allergy can and should be carried out in any clinical setting for all patients with this documentation. "If such allergies are routinely evaluated, patients will not needlessly avoid the beta-lactams that may be the best treatment for their infection and reduce the devel- opment of antibiotic resistance," Dr. Blumenthal said. n Late-career physicians more likely to prescribe long antibiotic courses By Anuja Vaidya P hysicians late in their career are more likely to prescribe anti- biotics for longer durations, according to a study published in Clinical Infectious Diseases. Researchers conducted a retrospective cohort analysis of family physicians in Ontario, Canada, between March 1, 2016, and Feb. 28, 2017. They defined prolonged antibiotic course prescribed as more than eight days of therapy. They included 10,616 family physicians, prescribing a total of 5.6 million antibiotic courses, in the study. The median proportion of prolonged antibiotic courses was 33.3 percent. Researchers found later career stage physicians, rural location and a larger pediatric practices were significantly associ- ated with greater prescription of prolonged courses. Additionally, late- and mid-career physicians were more likely to prescribe prolonged antibiotic courses as compared to early-career physicians. n Researchers uncover key step to how antibiotic resistance spreads in hospitals By Megan Knowles R esearchers at St. Louis-based Washington University School of Medicine found a key step in the transmis- sion of antibiotic resistance from one Acinetobacter bacterium to another, which helps reveal how drug resistance spreads through hospitals. The findings were published in Proceedings of the National Academy of Sciences. Acinetobacter strains carry the genetic blueprints for drug resistance on small loops of DNA called plasmids. The plasmids disable bacteria's self-defense systems so that they can inject copies of themselves into neighboring bacteria, conferring drug resistance on their bacterial neighbors, the researchers found. The researchers found that mutating the plasmids so they could not disrupt the bacteria's defenses stopped these plasmids from spreading and causing drug resistance. The findings provide a novel opening to interrupt the spread of drug resistance, the researchers said. Although the genes involved in the process have been identified, researchers must find compounds that stop plasmids from disrupting bacterial-defense systems. "If we found an inhibitor, we could clean hospital surfaces with it and prevent the dissemination of drug resistance," said senior author Mario Feldman, PhD. "We need to find therapies that don't kill the bacteria but prevent it from becoming drug-resistant, so we can continue using our antibiotics into the future." n

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