Feasibility of a Video Otoscope for Diagnosis of Otologic Pathology in the Pediatric Emergency Department

OBJECTIVES

Performing pediatric otoscopy can be difficult secondary to patient compliance, which potentiates misdiagnosis and inaccurate treatment of acute otitis media. This study used a convenience sample to assess the feasibility of using a video otoscope for the examination of tympanic membranes in children presenting to a pediatric emergency department.

METHODS

We obtained otoscopic videos using the JEDMED Horus + HD Video Otoscope. Participants were randomized to video or standard otoscopy, and a physician completed their bilateral ear examinations. In the video group, physicians reviewed otoscope videos with the patient's caregiver. The caregiver and physician completed separate surveys using a 5-point Likert Scale regarding perceptions of the otoscopic examination. A second physician reviewed each otoscopic video.

RESULTS

We enrolled 213 participants in 2 groups (standard otoscopy, n = 94; video otoscopy, n = 119). We used Wilcoxon rank sum, Fisher exact test, and descriptive statistics to compare results across groups. For physicians, there were no statistically significant differences between groups with ease of device use, quality of otoscopic view, or diagnosis. There was moderate agreement between physician video otoscopic view satisfaction and slight agreement between physician video otologic diagnosis. Estimates of length of time to complete the ear examinations were longer more often for the video otoscope compared with standard for both caregivers (OR, 2.00; 95% confidence interval, 1.10-3.70; P = 0.02) and physicians (OR, 3.08; 95% confidence interval, 1.67-5.78; P < 0.01). There were no statistically significant differences between video and standard otoscopy with regard to caregiver perception of comfort, cooperation, satisfaction, or diagnosis understanding.

CONCLUSIONS

Caregivers perceive that video otoscopy and standard otoscopy are comparable in comfort, cooperation, examination satisfaction, and diagnosis understanding. Physicians made a wider range of more subtle diagnoses with the video otoscope. However, examination length of time may limit the JEDMED Horus + HD Video Otoscope's feasibility in a busy pediatric emergency department.

Return visit rates after an emergency department discharge for children with sickle cell pain episodes

BACKGROUND

High return visit rates after hospitalization for people with sickle cell disease (SCD) have been previously established. Due to a lack of multicenter emergency department (ED) return visit rate data, the return visit rate following ED discharge for pediatric SCD pain treatment is currently unknown.

PROCEDURE

A seven-site retrospective cohort study of discharged ED visits for pain by children with SCD was conducted using the Pediatric Emergency Care Applied Research Network Registry. Visits between January 2017 and November 2021 were identified using previously validated criteria. The primary outcome was the 14-day return visit rate, with 3- and 7-day rates also calculated. Modified Poisson regression was used to analyze associations for age, sex, initial hospitalization rate, and a visit during the COVID-19 pandemic with return visit rates.

RESULTS

Of 2548 eligible ED visits, approximately 52% were patients less than 12 years old, 50% were female, and over 95% were non-Hispanic Black. The overall 14-day return visit rate was 29.1% (95% confidence interval [CI]: 27.4%-30.9%; site range 22.7%-31.7%); the 7- and 3-day return visit rates were 23.0% (95% CI: 21.3%-24.6%) and 16.7% (95% CI: 15.3%-18.2%), respectively. Younger children had slightly lower 14-day return visit rates (27.3% vs. 31.1%); there were no associations for site hospitalization rate, sex, and a visit occurring during the pandemic with 14-day returns.

CONCLUSION

Nearly 30% of ED discharged visits after SCD pain treatment had a return visit within 14 days. Increased efforts are needed to identify causes for high ED return visit rates and ensure optimal ED and post-ED care.

Bleeding after percutaneous coronary intervention and selection of candidates for long-term dual antithrombotic treatment

Background

The European Society of Cardiology recommends addition of a second antithrombotic drug (a P2Y12 inhibitor or rivaroxaban 2.5 mg twice daily) on top of aspirin in selected patients with chronic coronary syndrome (CCS) at high residual risk of ischemic events. However, this treatment increases bleeding risk, and identifying subsets of patients with the most favorable trade-off between ischemic and bleeding risk thus is essential. We hypothesized that patients undergoing percutaneous coronary intervention (PCI) who tolerate subsequent dual antiplatelet therapy (aspirin plus a P2Y12 inhibitor) without any bleeding complications selected themselves as candidates for prolonged dual antithrombotic therapy.

Methods and results

We included 30,531 patients with CCS treated with dual antiplatelet therapy after first-time PCI with a drug-eluting stent in Western Denmark (3.5 million inhabitants) from 1999 to 2018. Of these, 1,220 (4%) were hospitalized for bleeding within one year after PCI (bleeders) and 29,311 (96%) were not (non-bleeders). Patients were followed for maximum nine years (median follow-up 5.4 years). Bleeders had an increased nine-year risk of death (adjusted hazard ratio [aHR] 1.54, 95% CI 1.37–1.73) and hospitalization for bleeding (aHR 2.53, 95% CI 2.20–2.90). These associations were particularly strong for women. Looking at types of bleeding, the strongest predictors of death were gastrointestinal bleeding, cerebral bleeding, and anemia due to bleeding. Risks of myocardial infarction and ischemic stroke did not differ between bleeders and non-bleeders (Table). We then stratified non-bleeders according to their thromboembolic risk using the CHADS-P2A2RC score – a validated clinical risk prediction model developed to estimate thromboembolic risk in patients without atrial fibrillation. Non-bleeders with a high estimated thromboembolic risk (CHADS-P2A2RC score ≥4) had higher nine-year risks of myocardial infarction (hazard ratio [HR] 1.88, 95% CI 1.78–2.07), ischemic stroke (HR 3.02, 95% CI 2.66–3.43), hospitalization for bleeding (HR 1.98, 95% CI 1.81–2.16) and, in particular, death (HR 4.48, 95% CI 4.21–4.77) than non-bleeders with a low-to-moderate predicted risk (CHADS-P2A2RC score &lt;4).

Conclusions

Patients with CCS experiencing a bleeding event during the first year after first-time PCI had a substantially higher long-term risk of death and recurrent bleeding, but not a higher risk of ischemic events. Therefore, bleeding events during the first year after PCI may guide the preclusion of selected patients from long-term dual antithrombotic therapy. Among non-bleeders, the risk of ischemic events rose proportionately more than the risk of bleeding when comparing high-risk with low-risk patients. This is an important finding for clinicians, for whom accurate identification of patients at highest risk of ischemic events is an essential step in treatment allocation.

Funding Acknowledgement

Type of funding sources: None.

Diabetes is not a risk factor for myocardial infarction in patients without coronary artery disease

Background

Diabetes is considered a risk factor for myocardial infarction (MI). However, we have previously found that diabetes was not a short-term risk factor for MI in the absence of obstructive coronary artery disease (CAD).

Purpose

As long-term data are not available, we aimed to assess adverse cardiac events in patients with and without diabetes stratified by CAD up to 11 years after coronary angiography.

Methods

We conducted a cohort study of patients undergoing coronary angiography from 2003 to 2012 and followed them by cross-linking Danish health registries. Patients were stratified according to the presence/absence of CAD and diabetes. Outcomes included MI, cardiac death, all-cause death, and coronary revascularization.

Results

A total of 86,202 patients were included (diabetes: n=12,652). Median follow-up was 8.8 years. Using patients with neither CAD nor diabetes as reference (cumulative MI incidence 2.6%), the risk of MI was similar for patients with diabetes alone (3.2%; hazard ratio 1.202, 95% CI: 0.996–1.451), was increased for patients with CAD alone (9.3%; hazard ratio 2.75, 95% CI: 2.52–3.01), and was highest for patients with both CAD and diabetes (12.3%; hazard ratio 3.79, 95% CI: 3.43–4.20), see Figure. Similar associations were observed for cardiac death and coronary revascularization.

Conclusions

Diabetes patients without CAD by coronary angiography have a similar risk of MI compared to patients with neither CAD nor diabetes. In the presence of CAD, however, diabetes increases the risk of MI.

Figure 1

Funding Acknowledgement

Type of funding source: Public hospital(s). Main funding source(s): The Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark.

Cardiovascular risk of smoking in patients without obstructive coronary artery disease

Background

Smoking increases risk of cardiovascular disease by increasing atherosclerosis and thrombogenesis.

Purpose

We examined the impact of smoking on cardiovascular risk in patients without obstructive coronary artery disease (CAD) after coronary angiography.

Methods

We conducted a cohort study in patients without obstructive CAD examined by coronary angiography from 2003–2016 in Western Denmark and no previous history of MI or coronary revascularization. Smokers were compared with non-smokers (former/never smokers) and with an age- and sex matched comparison group sampled from the Western Denmark general population without a history of CAD. The main outcome was myocardial infarction (MI). Other outcomes were ischemic stroke and death. Maximum follow-up was 10 years. Adjusted hazards ratios (aHRs) were estimated using Cox regression.

Results

We identified 46,462 patients without obstructive CAD, of whom 10,879 (23%) were active smokers and 35,583 (77%) were non-smokers at the time of angiography. Patients were matched with 234,648 individuals from the general population with no previous MI or coronary revascularization. Median follow-up was 7.0 years. Smokers had higher risks of MI (aHR 1.65, 95% CI: 1.41–1.93), ischemic stroke (aHR 1.49, 95% CI: 1.28–1.74), and death (aHR 1.77, 95% CI: 1.67–1.87) compared to non-smokers undergoing CAG. As shown in the Figure, the MI risk increased immediately after start follow-up and the curves continued to diverge. Compared to the general population, smokers without obstructive CAD had a similar risk of MI (aHR 0.96, 95% CI: 0.83–1.10), but an increased risk of ischemic stroke (aHR 1.36, 95% CI: 1.19–1.56) and death (aHR 1.49, 95% CI: 1.41–1.56), while non-smokers had reduced risks of MI (aHR 0.57, 95% CI: 0.51–0.63), ischemic stroke (aHR 0.85, 95% CI: 0.78–0.93), and death (aHR 0.78, 95% CI: 0.75–0.81).

Conclusions

In patients without obstructive CAD by coronary angiography, active smoking was associated with a 65% increased 10-year risk of MI compared to non-smokers, suggesting a prothrombotic effect of smoking. Compared to a general population, with unknown CAD and smoking status, smokers examined by CAG had a similar or higher risk of cardiovascular events despite the absence of CAD, while non-smokers had a lower risk.

Figure 1

Funding Acknowledgement

Type of funding source: Public hospital(s). Main funding source(s): Department of Cardiology, Aarhus University Hospital

287Diabetes mellitus is a risk factor for ischemic stroke in patients with and without coronary artery disease after coronary angiography

Background

Diabetes (DM) and non-DM patients without coronary artery disease (CAD) by coronary angiography (CAG) have the same low risk of myocardial infarction.

Purpose

To study whether DM patients without CAD have the same risk of ischemic stroke as patients with neither DM nor CAD.

Methods

We conducted a cohort study of patients, who underwent CAG between 2004 and 2012 in the Western Denmark Heart Registry. Patients previously diagnosed with ischemic stroke or atrial fibrillation (AF) and those treated with an oral anticoagulant were excluded. Patients were stratified according to presence of DM and CAD. Follow-up started 30 days after CAG. We computed event rates and adjusted incidence rate ratios (IRRs) using patients with neither DM nor CAD as reference.

Results

A total of 68,829 patients were included. Median follow-up was 4.0 years. Patients with both DM and CAD were at the highest risk of ischemic stroke (1.25 events per 100 person-years; adjusted IRR 2.10, 95% CI 1.77–2.48) (Figure 1). Patients with CAD alone (0.70 events per 100 person-years; adjusted IRR 1.29, 95% CI 1.12–1.48) or DM alone (0.84 events per 100 person-years; adjusted IRR 1.79, 95% CI 1.41–2.26) were at intermediate risk while patients with neither DM nor CAD (0.46 events per 100 person-years) were at lowest risk. Among DM patients, extent of CAD was further predictive of risk (ptrend<0.001).

Figure 1

Conclusions

Not only CAD but also DM independently predict the risk of ischemic stroke after CAG. Their combination further increases the risk of ischemic stroke depending on the extent of CAD.

P1527The applicability of the dual pathway approach criteria after coronary angiography

Background

The combination of aspirin and low-dose rivaroxaban (dual pathway approach, DPA) has been approved for high-risk patients with stable coronary artery disease (CAD) in the COMPASS trial. Patients with CAD combined with ≥1 DPA criteria, defined as peripheral artery disease, renal failure, heart failure, or diabetes, have been proposed as high-risk patients eligible for DPA.

Purpose

To determine the prevalence of patients meeting the DPA criteria and the association with major adverse cardiovascular events (MACE) in patients with stable CAD after coronary angiography (CAG). Further, to evaluate use of the DPA criteria in CAD patients meeting the inclusion criteria in the COMPASS trial.

Methods

We studied patients included in the Western Denmark Heart Registry after examination by CAD 2004–11. Patients without CAD or myocardial infarction (MI) <1 year before or 30 days after CAG were excluded. Patients were stratified according to 0 or ≥1 DPA criteria and being eligible/ineligible for the COMPASS trial. Event rates and incidence rate ratios (IRRs) of MACE (cardiac death, ischemic stroke, and MI) were estimated.

Results

Of 80,071 patients undergoing CAG, 18,689 (23%) patients had stable CAD. According to the DPA criteria, 7,730 patients (10%) were DPA eligible. Rates of MACE were 1.98 (95% CI 1.86–2.34) events per 100 person-years among DPA ineligible patients and 4.26 (95% CI 4.04–4.50) events per 100 person-years among DPA eligible patients (IRR 2.15, 95% CI 1.98–2.34). When stratifying patients according to eligibility in the COMPASS inclusion criteria, COMPASS eligible patients with 0 DPA criteria and COMPASS ineligible patients with ≥1 DPA criteria were at intermediate risk compared to patients meeting both (high risk) or none (low risk) of these criteria (Figure 1).

Figure 1

Conclusion

In a cohort of consecutive patients undergoing CAG, 1 in 10 patients would be eligible for DPA according to the DPA criteria. Patients with stable CAD and ≥1 DPA criteria had >2-fold higher rate of MACE than CAD patients without any DPA criteria.

Bacteriophage structure

The purpose of this review is to provide information of the role played by electron microscopy in respect of bacteriophage structure. This 40 years' "love story" between phages and microscopy was a valuable contribution to the progress of scientific knowledge in molecular biology. In spite of the rather drastic treatment required for electron microscopical analysis, it was possible to reveal the molecular organization and morphogenic pathway of many of the bacteriophages cited in this paper.

Physiological, morphological, and physicochemical characterization of a novel Escherichia coli bacteriophage, phage MM

A double-stranded DNA containing, T even-like, Escherichia coli bacteriophage, called MM, has been isolated from the local sewage and purified by polyethylene glycol precipitation followed by banding on a cesium chloride three-step gradient. It yields a burst size of 75 particles per infected cell, and has an adsorption coefficient of 3.3 x 10(-10) cm3/min and a latent period of 45 min. Electron microscopy of phage MM reveals an isometric icosahedral head, 92 nm long and 81 nm wide, and a 112-nm-long contractile tail with six pairs of 40-nm-long fibers attached to its baseplate. Phage MM appears similar to E. coli phage T4 or Salmonella phage O1. The density of phage MM in cesium chloride is 1.515 g/ml, and its total mass is 144 MDa. Gel electrophoresis of purified MM capsids displays two major capsid proteins in approximately equimolar amounts and with apparent molecular masses of 38 and 15 kDa. Similarly, purified MM tails yield two major polypeptides with apparent molecular masses of 55 and 16 kDa, most likely representing the major tail sheath and tail tube polypeptides. Its double-stranded DNA has a G-C content of 50%, a length of 131 kilobases (kb), and a mass of 89 MDa.

Length and shape variants of the bacteriophage T4 head: mutations in the scaffolding core genes 68 and 22

The shape and size of the bacteriophage T4 head are dependent on genes that determine the scaffolding core and the shell of the prohead. Mutants of the shell proteins affect mainly the head length. Two recently identified genes (genes 67 and 68) and one already known gene (gene 22), whose products are scaffold constituents, have been investigated. Different types of mutants were shown to strongly influence the proportion of aberrantly shaped particles. By model building, these shape variants could be represented as polyhedral bodies derived from icosahedra, through outgrowths along different polyhedral axes. The normal, prolate particle is obtained by elongation along a fivefold axis. The mutations of the three core genes (genes 67, 68, and 22) affect the width mainly by lateral outgrowths of the prolate particle, although small and large isometric particles are also found. Many of the aberrant particles are multitailed, suggesting a correlation between tail attachment sites and shape.

Head structure of bacteriophages T2 and T4

The length-to-width ratios of bacteriophage T2 and T4 heads and stereometric angles specifying the prolate icosahedral T2 capsid were evaluated on electron micrographs recorded from samples prepared by a variety of methods. The copy numbers of the major capsid protein, gp23*, of T2 and T4 phages were compared by quantitative gel electrophoresis. Taken together, the resulting values are most compatible with triangulation numbers T = 13 and Q = 21 for both T2 and T4, thus confirming the previously proposed capsid architecture of T4 revealed by indirect measurements and thereby eliminating the repeatedly reported discrepancy between T2 and T4 in favor of a common Q number of 21 corresponding to 960 copies of gp23*.

The efficiency of immunolabel on Lowicryl sections compared to theoretical predictions

The surface of thin sections of aldehyde-fixed biological material shows a specimen-related relief of 2-6 nm with Lowicryl. Epon sections are about three times smoother. The relief is the consequence of thin-sectioning being in reality a cleavage. Epitopes are supposed to be laid open (or set free) because cleavage follows the interfaces between protein and Lowicryl. We have developed a simple theory on this basis and have theoretically estimated the efficiency of on-section labeling and compared it with experimental data. For randomly dispersed proteins in cytoplasm, Lowicryl sections will yield significant label only when the concentration of the antigen is about 10 microM or more. The complex situation of more compact proteins, as represented by fibers, sheets, and biological membranes is discussed and the difficulty of significant calculations is explained. Pre-embedding labeling and melted cryosections should give 10-30 times more label. The possible reasons for the observed much smaller gain of not more than two to three times are discussed.

The wrapping phenomenon in air-dried and negatively stained preparations

We demonstrate that the interface energies involved in the direct preparation of supramolecular structures onto supporting films leads very frequently to a smooth wrapping of the supporting film around approximately one third to one half of the structure. We conclude that in such cases the structure is more rigid than the supporting film; examples being ribosomes, small viruses and small glass fragments. Other structures are less rigid and become significantly flattened. Complete flattening is frequently observed with empty virus capsids. The sandwich technique, by which a specimen is placed between two supporting films, in general leads to increased flattening. Only in few cases (e.g. ribosomes) are biological particles rigid enough to resist flattening and become wrapped from both sides.

Paracrystalline arrays of protein-synthesis elongation factor Tu. Comparison with polymerized actin

Homogeneous protein synthesis elongation factor Tu from Escherichia coli forms aggregates at high concentrations of ammonium sulfate which have a filamentous appearance in the light microscope. Electron microscopy of negatively stained preparations shows that these aggregates are paracrystalline, including three different forms. On the basis of analyses by optical diffraction, this polymorphism can be explained in terms of three different tubular foldings of the same basic two-dimensional surface lattice. This can be compared with that underlying the structure of actin filaments, thus providing a crucial test of the putative relationship between the elongation factor and actin [Rosenbusch, J. P. et al. (1976) J. Supramol. Struct. 5, 391-396]. The differences between the surface lattices, in conjunction with the negative results of sensitive immunochemical tests for possible cross-reactivities between the two proteins, suggest that any such relationship is very remote.

Capsid transformation during packaging of bacteriophage lambdaDNA

Assembly pathways of complex viruses might not be simple additions of one protein after another with rigid tertiary structure. It might in fact involve shifts in subunit structure, movement of subunits relative to each other to form new arrangements, transient action of proteins and protein segments, involvement of structure forming 'microenvironments' of the host. Thus morphogenesis of the bacteriophage lambda head starts with the formation of a core-containing DNA-free petit lambda particle. In a first transition, and dependent on a host function, the core is released, minor protein components of the capsid are processed and the particle's structure is altered, as shown by a change of its hydrodynamic properties. The resulting 'prehead' undergoes a second transition triggered by a complex of DNA and recognition protein (A-protein). This transition is more drastic than the first one. The particle doubles its volume without increasing in protein mass, the shell becomes thinner, and the surface structure is changed. Concomitantly with this process, the DNA becomes packaged and the particle becomes able to bind the small 'D-protein' in amounts equimolar to the capsid protein, which it could not do before. The D-protein addition probably causes another shift of the capsid structure. DNA packaging is completed, and the DNA is cut from concatemeric precursors to unit length molecules. Binding sites are created for the tail connector molecules which in turn allow the independently assembled tail to attach. Research on these processes proceeds along several lines: comparison of physical and chemical properties of particles accumulating in mutants; pulse-chase experiments on assembly precursors; morphogenesis in vitro; and model transitions of aberrant lambda polyheads.