Becker's Clinical Quality & Infection Control

46 ANTIBIOTIC RESISTANCE & STEWARDSHIP Antibiotic, PPI use may increase pediatric C. diff risk By Anuja Vaidya C hildren using antibiotics and/or proton pump inhibitors face a higher risk of developing Clostridioides difficile infection, according to a study published in Infection Control & Hospital Epidemiology. Researchers conducted a meta-analysis and systematic review of studies from the Medline, Web of Science, Scopus and Embase databases. They searched for subject headings and text words related to C. diff and pedi- atrics from 1975 to 2017. They screened 2,033 articles and found 14 stud- ies involving more than 10 million children that met the inclusion criteria. Of the 10 million-plus children, 22,320 developed C. diff infection. They found that prior antibiotic exposure and PPI use were associated with an increased risk of C. diff in children. However, subgroup analyses using studies that only reported adjusted results found prior antibiotic exposure may not be a significant risk factor for C. diff. n Over 5-year period, antimicrobial stewardship programs saved US hospitals $732 per patient By Anuja Vaidya A study published in Antimicrobial Resistance & Infection Control examined the economic and clinical impact of antimicrobial stewardship programs. Researchers conducted a search within the Embase and Medline databas- es to find primary research studies in English, published between Sept. 30, 2014, and Dec. 31, 2017. They identified 146 studies that evaluated patient and/or economic outcomes after implementation of hospital an- timicrobial stewardship programs, including length of stay, antimicrobial use and total costs. The studies were conducted in North America (49 percent), Europe (25 percent), Asia (14 percent), Africa (3 percent), South America (3 percent) and Australia (3 percent). Most of the studied were conducted in hospitals with 500 to 1,000 beds. After the implementation of antimicrobial stewardship programs, 85 per- cent of the reviewed studies demonstrated a decrease in length of stay and 92 percent showed a decrease in antibiotic expenditure. Researchers also found that mean cost savings varied by hospital size and region after antimicrobial stewardship program implementation. Among U.S.-based studies, average cost savings were approximately $732 per patient, with Europe showing similar trends. The reduction in length of stay was the main driver of cost savings. n Researchers pinpoint mechanism that makes bacteria resistant to antibiotics By Megan Knowles P hysicists at McMaster University in Ontar- io, Canada, identified a simple mechanism deadly bacteria use to fend off antibiotics, a study published in Nature Communications Biology found. e researchers looked at how membranes of bacteria interacted with the antibiotic polymyxin B — a drug commonly used to treat urinary tract infections, meningitis, blood and eye infections. ey concentrated on this antibiotic since it was once considered the strongest drug of its kind. Its strength came into question in 2016 aer Chinese scientists discovered a gene that let bacteria become resistant to polymyxins. "We wanted to find out how this bacteria, specifi- cally, was stopping this drug in this particular case," said first study author Adree Khondker. "If we can understand that, we can design better antibiotics." e study used methods physicists usually employ for materials research to look deeper into the bacterial membrane. By using imaging and simulations, the researchers found the part of the antibiotic that enters the membrane, where it en- ters and how deeply it penetrates. ey simulated these processes on microsecond timescales with high-end gaming computers in their lab. e team determined that when a bacterium has become resistant, its membrane is more rigid and the charge is weaker, making it less attractive to the drug and harder to penetrate. "For the drug, it's like going from cutting Jello to cutting through rock," Mr. Khondker explained. "ere has been a lot of speculation about this mech- anism," said lead study author Maikel Rheinstädter. "But for the first time we can prove the membrane is more rigid and the process is slowed." n C M Y CM MY CY CMY K

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