Effect of Rapid Respiratory Virus Testing on Antibiotic Prescribing Among Children Presenting to the Emergency Department With Acute Respiratory Illness: A Randomized Clinical Trial

IMPORTANCE

There is high usage of antibiotics in the emergency department (ED) for children with acute respiratory illnesses. Studies have reported decreased antibiotic use among inpatients with rapid respiratory pathogen (RRP) testing.

OBJECTIVE

To determine whether RRP testing leads to decreased antibiotic use and health care use among children with influenzalike illness (ILI) in an ED.

DESIGN, SETTING, AND PARTICIPANTS

A randomized clinical trial among children aged 1 month to 18 years presenting to an ED with ILI from December 1, 2018, to November 30, 2019, was conducted. Data were analyzed March 23, 2020, to April 2, 2021. All children received a nasopharyngeal swab for RRP testing and were randomized 1:1 to the intervention group or control group (results not given, routine clinical care). Results were available in 45 minutes. Intention-to-treat analyses and modified intention-to-treat (clinician knows results) analyses were conducted using multivariable Poisson regression.

INTERVENTIONS

Rapid respiratory pathogen test results given to clinicians.

MAIN OUTCOMES AND MEASURES

Antibiotic prescribing was the primary outcome; influenza antiviral prescribing, ED length of stay, hospital admission, and recurrent health care visits were the secondary outcomes.

RESULTS

Among 931 ED visits (intervention group, 452 children group and control group, 456 children after exclusion of those not meeting criteria or protocol violations), a total of 795 RRP test results (85%) were positive. The median age of the children was 2.1 years (interquartile range, 0.9-5.6 years); 509 (56%) were boys. Most children (478 [53%]) were Hispanic, 688 children (76%) received government insurance, and 314 (35%) had a high-risk medical condition. In the intention-to-treat intervention group, children were more likely to receive antibiotics (relative risk [RR], 1.3; 95% CI, 1.0-1.7), with no significant differences in antiviral prescribing, medical visits, and hospitalization. In inverse propensity-weighted modified intention-to-treat analyses, children with test results known were more likely to receive antivirals (RR, 2.6; 95% CI, 1.6-4.5) and be hospitalized (RR, 1.8; 95% CI, 1.4-2.5); there was no significant difference in antibiotic prescribing (RR, 1.1; 95% CI, 0.9-1.4).

CONCLUSIONS AND RELEVANCE

The use of RRP testing in the ED for ILI did not decrease antibiotic prescribing in this randomized clinical trial. There is a limited role for RRP pathogen testing in children in this setting.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03756753.

Development of an instrument for measuring self-efficacy in cell biology

This article describes the development of a ten-item scale to assess biology majors' self-efficacy towards the critical thinking and data analysis skills taught in an upper-division cell biology course. The original seven-item scale was expanded to include three additional items based on the results of item analysis. Evidence of reliability and validity was collected and reported for the revised scale. In addition, the effect of varying the number of response categories presented with the items was empirically examined by administering different versions of the instrument containing 6, 11, 21, and 101 response categories to randomly selected samples of students in the course. Rasch scaling procedures were used to analyze the results. Contrary to Bandura's recommendation for using the 101-point scale (0-100), the results indicated that most respondents used only a subset of the options in the 101-point scale and that the 6-point and 11-point scales produced less threshold disordering for the purpose of assessing changes in students' self-efficacy in the context of a one-semester course.

Rethinking exams and letter grades: how much can teachers delegate to students?

In this article we report a 3-yr study of a large-enrollment Cell Biology course focused on developing student skill in scientific reasoning and data interpretation. Specifically, the study tested the hypothesis that converting the role of exams from summative grading devices to formative tools would increase student success in acquiring those skills. Traditional midterm examinations were replaced by weekly assessments administered under test-like conditions and followed immediately by extensive self, peer, and instructor feedback. Course grades were criterion based and derived using data from the final exam. To alleviate anxiety associated with a single grading instrument, students were given the option of informing the grading process with evidence from weekly assessments. A comparative analysis was conducted to determine the impact of these design changes on both performance and measures of student affect. Results at the end of each year were used to inform modifications to the course in subsequent years. Significant improvements in student performance and attitudes were observed as refinements were implemented. The findings from this study emphasized the importance of prolonging student opportunity and motivation to improve by delaying grade decisions, providing frequent and immediate performance feedback, and designing that feedback to be maximally formative and minimally punitive.

Teaching cell biology in the large-enrollment classroom: methods to promote analytical thinking and assessment of their effectiveness

A large-enrollment, undergraduate cellular biology lecture course is described whose primary goal is to help students acquire skill in the interpretation of experimental data. The premise is that this kind of analytical reasoning is not intuitive for most people and, in the absence of hands-on laboratory experience, will not readily develop unless instructional methods and examinations specifically designed to foster it are employed. Promoting scientific thinking forces changes in the roles of both teacher and student. We describe didactic strategies that include directed practice of data analysis in a workshop format, active learning through verbal and written communication, visualization of abstractions diagrammatically, and the use of ancillary small-group mentoring sessions with faculty. The implications for a teacher in reducing the breadth and depth of coverage, becoming coach instead of lecturer, and helping students to diagnose cognitive weaknesses are discussed. In order to determine the efficacy of these strategies, we have carefully monitored student performance and have demonstrated a large gain in a pre- and posttest comparison of scores on identical problems, improved test scores on several successive midterm examinations when the statistical analysis accounts for the relative difficulty of the problems, and higher scores in comparison to students in a control course whose objective was information transfer, not acquisition of reasoning skills. A novel analytical index (student mobility profile) is described that demonstrates that this improvement was not random, but a systematic outcome of the teaching/learning strategies employed. An assessment of attitudes showed that, in spite of finding it difficult, students endorse this approach to learning, but also favor curricular changes that would introduce an analytical emphasis earlier in their training.

Neutrophil priming: pathophysiological consequences and underlying mechanisms

1. Neutrophil priming by agents such as tumour necrosis factor-alpha, granulocyte/macrophage colony-stimulating factor and lipopolysaccharide causes a dramatic increase in the response of these cells to an activating agent; this process has been shown to be critical for neutrophil-mediated tissue injury both in vitro and in vivo. 2. The principle consequence of priming, aside from a direct effect on cell polarization, deformability and integrin/selectin expression, is to permit secretagogue-induced superoxide anion generation, degranulation and lipid mediator (e.g. leukotriene B4 and arachidonic acid) release. It is now recognized that most priming agents also serve an additional function of delaying apoptosis and hence increasing the functional longevity of these cells at the inflamed site. 3. The potential mechanisms underlying priming are discussed; current data suggest a dissociation between priming and changes in receptor number and/or affinity, G-protein expression, phospholipase C and phospholipase A2 activation and changes in intracellular Ca2+ concentration. However, more recent studies support a key role for protein tyrosine phosphorylation and enhanced phospholipase D and phosphoinositide 3-kinase activity in neutrophil priming. 4. Recent work has also revealed the potential for neutrophils to spontaneously and fully 'de-prime' after an initial challenge with platelet-activating factor. This ability of neutrophils to undergo a complete cycle of priming-de-priming (and re-priming) reveals a previously unrecognized flexibility in the control of neutrophil behaviour at an inflamed site.

Demonstration of reversible priming of human neutrophils using platelet-activating factor

Exposure of neutrophils to agents such as lipopolysaccharide, tumor necrosis factor-alpha (TNF-alpha), and the granulocyte-macrophage colony-stimulating factor causes a major upregulation of subsequent agonist-induced NADPH oxidase activation. This priming effect is a prerequisite for neutrophil-mediated tissue damage and has been widely considered to be an irreversible process. We have investigated the potential for neutrophils to recover from a priming stimulus by studying the effects of platelet-activating factor (PAF). PAF did not stimulate respiratory burst activity directly, but caused a rapid (maximal at 10 minutes) and concentration-dependent (EC50 50.2 nmol/L) increase in N-formyl-methionyl-leucyl-phenylalanine (fMLP)-stimulated superoxide anion release. At time-points > 10 minutes, this priming effect spontaneously declined, with return to basal levels of fMLP-stimulated superoxide anion generation by 120 minutes. An identical priming time-course was observed with N-methyl carbamyl PAF, a nonmetabolizable analogue of PAF, indicating that the transient nature of PAF-induced priming was not secondary to PAF metabolism. Two structurally diverse PAF receptor antagonists (UK-74,505 and WEB 2086), added 10 minutes after PAF addition, increased the rate of decay of the priming effect. In contrast, TNF-alpha-induced priming, which was of a similar magnitude to that observed for PAF, was slower to evolve (maximal at 30 minutes) and remained constant for at least 120 minutes. The reversible nature of PAF-induced priming was confirmed by demonstrating that PAF-, but not TNF-alpha-, induced cell polarization (shape change) and CD11b-dependent neutrophil binding of albumin-coated latex beads was also transient, with return to basal, unstimulated levels by 120 minutes. Furthermore, cells that had spontaneously deprimed following PAF exposure retained their capacity to be fully reprimed by a subsequent addition of either PAF or TNF-alpha. These data imply that neutrophil priming is not an irreversible event: the demonstration of a cycle of complete priming, depriming, and repriming offers the potential for functional recycling of neutrophils at sites of inflammation.

Characterization of inositol hexakisphosphate (InsP6)-mediated priming in human neutrophils: lack of extracellular [3H]-InsP6 receptors

1. Inositol hexakisphosphate (InsP6) is a ubiquitous and abundant cytosolic inositol phosphate that has been reported to prime human neutrophils for enhanced agonist-stimulated superoxide anion generation. This led to the proposal that the release of InsP6 from necrotic cells may augment the functional responsiveness of neutrophils at an inflammatory focus. The aim of this study was to examine whether the functional effects of InsP6 in neutrophils are receptor-mediated and establish the magnitude of this priming effect relative to other better characterized priming agents. 2. Analysis of [3H]-InsP6 binding to human neutrophil membranes in 20 mM Tris, 20 mM NaCl, 100 mM KCl, 5 mM EDTA (pH 7.7) buffer using 0.1 mg ml-1 membrane protein and 2.5 nM [3H]-InsP6 (90 min, 4 degrees C), demonstrated specific low affinity [3H]-InsP6 binding that was non-saturable up to a radioligand concentration of 10 nM. 3. [3H]-InsP6 displacement by InsP6 gave a Hill coefficient of 0.55 and best fitted a two-site logistic model (53% KD 150 nM, 47% KD 5 microM). [3H]-InsP6 binding also displayed low (3 fold) selectivity for InsP6 over Ins(1,3,4,5,6)P5. 4. The specific [3H]-InsP6 binding displayed a pH optimum of 8, was abolished by pre-boiling the membranes, and was enhanced by Ca2+, Mg2+ and Na+. 5. In incubations with intact neutrophils, where high levels of specific [3H]-LTB4 binding was observed, no [3H]-InsP6 binding could be identified. 6. Preincubation of neutrophils with 100 microM InsP6 had no effect on resting cell morphology, but caused a minor and transient (maximal at 30 s) enhancement of (0.1 nM) fMLP-induced shape change (% cells shape changed: fMLP 53 +/- 3%, fMLP+InsP6 66 +/- 4%). Similarly, InsP6 (100 microM, 30 s) had no effect on basal superoxide anion generation and, compared to lipopolysaccharide (LPS, 100 ng ml-1, 60 min), tumour necrosis factor-alpha (TNF alpha, 200 u ml-1, 30 min) or platelet-activating factor (PAF, 100 nM, 5 min) caused only a small enhancement of 100 nM fMLP-stimulated superoxide anion generation (fold-increase in superoxide anion generation over fMLP alone: InsP6 1.8 +/- 0.3, LPS 6.8 +/- 0.6, TNF alpha 5.2 +/- 0.7, PAF 5.8 +/- 0.6). 7. While these data support the presence of a specific, albeit low affinity, [3H]-InsP6 binding site in human neutrophil membrane preparations, the lack of binding to intact cells implies that the functional effects of InsP6 (ie. enhanced fMLP-stimulated superoxide anion generation and shape change) are not receptor-mediated.