Practice Versus Potential: The Impact of the BioFire FilmArray Pneumonia Panel on Antibiotic Use in Children.

BACKGROUND: The BioFire FilmArray Pneumonia Panel (BFPP), a multiplex PCR panel for the diagnosis of lower respiratory tract infections, has been proposed as a tool for antimicrobial stewardship. Few studies evaluate real-world implementation of the BFPP and no studies focus exclusively on children. Our institution implemented BFPP testing without restrictions. METHODS: We conducted a retrospective cohort study in children hospitalized at St. Louis Children's Hospital to (1) characterize the use of the BFPP in pediatric patients and (2) assess how results impacted antibiotic use. We included all BFPP tests obtained during the first year after the introduction of the test, September 2021 through August 2022. The primary outcome was change in antibiotic therapy within 24 hours of results, which was compared to the potential change in antibiotic therapy determined by two infectious diseases clinicians. RESULTS: One hundred sixty-nine tests from 126 patients were included. Nine patients were immunocompromised and 19 had chronic tracheostomy. The majority of tests were sent from tracheal aspirate specimens (92%) and from patients in an intensive care unit (94%). Only 51% of tests were obtained due to respiratory failure or suspected pneumonia. For 80% of test results, there was potential to change antibiotics, but change occurred in only 46% of tests in practice. Antibiotic escalation was more common (26%) than de-escalation (15%) or discontinuation (4.1%). CONCLUSIONS: In a cohort of pediatric patients tested with the BFPP, the majority of tests were sent from tracheal aspirates and less than half of tests were associated with a change in antibiotics.

Invasive Community-Onset Gram-Positive Infections From July 2018 Through December 2022 at 2 Children's Hospitals.

Background: Invasive infections caused by Streptococcus pyogenes (invasive group A streptococcus [iGAS]) and Streptococcus pneumoniae (invasive pneumococcal disease [IPD]) decreased substantially at the beginning of the COVID-19 pandemic. Our study sought to evaluate the extent of this decrease and the trends of these infections since reversion of societal adjustments incident to the pandemic. We also wanted to compare the frequency of these infections with invasive community-onset Staphylococcus aureus (I-CO-SA) infections and common respiratory viral infections in this period. Methods: Cases of iGAS, IPD, and I-CO-SA infections were identified prospectively and retrospectively at 2 large US children's hospitals by positive cultures from July 2018 through December 2022. Admission data were used to estimate frequency. For comparison, rates of respiratory syncytial virus (RSV), influenza, and SARS-CoV-2 were estimated by the number of positive viral test results at each institution. Results: I-CO-SA infections showed little variation in the study period. Rates of iGAS infection and IPD decreased by 46% and 44%, respectively, from 2019 to 2020, coinciding with a substantial decrease in RSV and influenza. In 2022, RSV and influenza infection rates increased to prepandemic winter season rates, coinciding with a return to prepandemic rates of IPD (225% increase from 2021 to 2022) and a surge above prepandemic rates of iGAS infections (543% increase from 2021 to 2022). Conclusions: The COVID-19 pandemic had an unexpected influence on IPD and iGAS infections that was temporally related to changes in rates of viral infections.

Molecular cloning, overexpression, and an efficient one-step purification of α5ß1 integrin.

The α5ß1 integrin heterodimer is involved in many cellular processes and is an anti-cancer therapeutic target. Therefore, access to quantities of protein suitable for studies aimed at understanding its biological functions is important. To this end, a large-scale protein expression system, utilizing the recombinant baculovirus/SF9 insect cell expression system, was created to produce the extracellular domain of the α5ß1 integrin. An incorporated 8X-histidine tag enabled one-step nickel-column purification. Following sequence confirmation by LC-MS/MS, the conformation of the heterodimer was characterized by native dot blot and negative stain electron microscopy. Cellular transduction inhibition studies confirmed biological activity. The system allows expression and purification of α5ß1 integrin in quantities suitable for an array of different experiments including structural biology.