Assessing the interrater and intrarater reliability of subglottic stenosis grading systems

BACKGROUND

Subglottic stenosis (SGS) is a condition leading to narrowing of the upper airway which can lead to dyspnea and life-threatening airway obstruction. Although other proposed grading systems exist, the Cotton Myer (CM) and percent stenosis systems are the most widespread in clinical practice. Despite this, the CM system has not yet been validated for visual assessment of SGS.

OBJECTIVE

To determine the interrater and intrarater reliability of the CM grading system among a cohort of physicians who manage patients with SGS.

METHODS

An online survey created with videos of tracheoscopies from 20 adult patients with subglotticstenosis (SGS) was sent individually to 9 expert physicians from various medical specialties, all of whom managed patients with SGS. Physicians were asked to view the 20 tracheoscopy videos and assess both the percent stenosis and Cotton Myer (CM) grade of each patient. After a period of 4 weeks, the physicians were sent the same survey of the 20 tracheoscopy videos. The interrater and intrarater reliability was calculated using the intraclass correlation coefficient (ICC), a measurement used to evaluate the reliability (the extent to which a measurement can be replicated) of two or more raters measuring the same subject.

RESULTS

Overall, CM and percent stenosis systems were found to have an ICC of 0.94 and 0.90 within the domain of interrater reliability, respectively, and ICC of 0.71 and 0.81 within the domain of intrarater reliability, respectively.

CONCLUSION

Our findings suggest that the CM and percent stenosis grading systems remain a valid clinical tool to measure and communicate the severity of airway obstruction in SGS.

Cell-free DNA methylation analysis as a marker of malignancy in pleural fluid

Diagnosis of malignant pleural effusion (MPE) is made by cytological examination of pleural fluid or histological examination of pleural tissue from biopsy. Unfortunately, detection of malignancy using cytology has an overall sensitivity of 50%, and is dependent upon tumor load, volume of fluid assessed, and cytopathologist experience. The diagnostic yield of pleural fluid cytology is also compromised by low abundance of tumor cells or when morphology is obscured by inflammation or reactive mesothelial cells. A reliable molecular marker that may complement fluid cytology for the diagnosis of malignant pleural effusion is needed. The purpose of this study was to establish a molecular diagnostic approach based on pleural effusion cell-free DNA methylation analysis for the differential diagnosis of malignant pleural effusion and benign pleural effusion. This was a blind, prospective case-control biomarker study. We recruited 104 patients with pleural effusion for the study. We collected pleural fluid from patients with: MPE (n = 48), indeterminate pleural effusion in subjects with known malignancy or IPE (n = 28), and benign PE (n = 28), and performed the Sentinel-MPE liquid biopsy assay. The methylation level of Sentinel-MPE was markedly higher in the MPE samples compared to BPE control samples (p < 0.0001) and the same tendency was observed relative to IPE (p = 0.004). We also noted that the methylation signal was significantly higher in IPE relative to BPE (p < 0.001). We also assessed the diagnostic efficiency of the Sentinel-MPE test by performing receiver operating characteristic analysis (ROC). For the ROC analysis we combined the malignant and indeterminate pleural effusion groups (n = 76) and compared against the benign group (n = 28). The detection sensitivity and specificity of the Sentinel-MPE test was high (AUC = 0.912). The Sentinel-MPE appears to have better performance characteristics than cytology analysis. However, combining Sentinel-MPE with cytology analysis could be an even more effective approach for the diagnosis of MPE. The Sentinel-MPE test can discriminate between BPE and MPE. The Sentinel-MPE liquid biopsy test can detect aberrant DNA in several different tumor types. The Sentinel-MPE test can be a complementary tool to cytology in the diagnosis of MPE.

Optimization of Subglottic View During Flexible Laryngoscopy With Patient Positioning

OBJECTIVE

Determine the ideal head position to optimize visualization of the subglottis using flexible laryngoscopy.

STUDY DESIGN

Prospective cohort study.

SETTING

Outpatient multidisciplinary airway clinic at a tertiary care center.

METHODS

Patients presenting to a multidisciplinary airway clinic undergoing nasoendoscopic airway examination were enrolled. Three head positions were utilized to examine the subglottis during laryngoscopy: "sniffing," chin tuck, and stooping positions. In-office reviewers and blinded clinician participants evaluated views of the airway based on Cormack-Lehane (CL) scale, airway grade (AG), and visual analog scale (VAS). Demographic data were obtained. Statistical analysis compared head positions and demographic data using Student's t test, analysis of variance, and Tukey's post hoc analysis.

RESULTS

One hundred patients participated. No statistical differences existed among in-clinic or blinded reviewers for the CL score in any head position (p = .35, .5, respectively). For both AG and VAS, flexed and stooping positions were rated higher than the sniffing positions by both in-clinic and blinded reviewers (p < .01 for all analyses), but there was no statistical difference between these two positions (p = .28, .18, respectively). There was an inverse correlation between age and scores for AG and VAS in the flexed position for both sets of reviewers (p = .02, <.01 respectively), and a higher body mass index was significantly associated with the need to perform tracheoscopy for full airway evaluation (p < .01).

CONCLUSION

Both flexion and stoop postures can be implemented by an experienced endoscopist in awake, transnasal flexible laryngoscopy to enhance visualization of the subglottic airway.

Cell-Free DNA Methylation Analysis as a Marker of Malignancy in Pleural Fluid

Background

Diagnosis of malignant pleural effusion (MPE) is made by cytological examination of pleural fluid or histological examination of pleural tissue from biopsy. Unfortunately, detection of malignancy using cytology has an overall sensitivity of 50%, and is dependent upon tumor load, volume of fluid assessed, and cytopathologist experience. The diagnostic yield of pleural fluid cytology is also compromised by low abundance of tumor cells or when morphology is obscured by inflammation or reactive mesothelial cells. A reliable molecular marker that may complement fluid cytology malignant pleural effusion diagnosis is needed. The purpose of this study was to establish a molecular diagnostic approach based on pleural effusion cell-free DNA methylation analysis for the differential diagnosis of malignant pleural effusion and benign pleural effusion.

Results

This was a blind, prospective case-control biomarker study. We recruited 104 patients with pleural effusion for the study. We collected pleural fluid from patients with: MPE (n = 48), PPE (n = 28), and benign PE (n = 28), and performed the Sentinel-MPE liquid biopsy assay. The methylation level of Sentinel-MPE was markedly higher in the MPE samples compared to BPE control samples (p < 0.0001) and the same tendency was observed relative to PPE (p = 0.004). We also noted that the methylation signal was significantly higher in PPE relative to BPE (p < 0.001). We also assessed the diagnostic efficiency of the Sentinel-MPE test by performing receiver operating characteristic analysis (ROC). For the ROC analysis we combined the malignant and paramalignant groups (n = 76) and compared against the benign group (n = 28). The detection sensitivity and specificity of the Sentinel-MPE test was high (AUC = 0.912). The Sentinel-MPE appears to have better performance characteristics than cytology analysis. However, combining Sentinel-MPE with cytology analysis could be an even more effective approach for the diagnosis of MPE.

Conclusions

The Sentinel-MPE test can discriminate between BPE and MPE. The Sentinel-MPE liquid biopsy test can detect aberrant DNA in several different tumor types. The Sentinel-MPE test can be a complementary tool to cytology in the diagnosis of MPE.

Efficacy and Safety of Ensovibep for Adults Hospitalized With COVID-19 : A Randomized Controlled Trial

BACKGROUND

Ensovibep (MP0420) is a designed ankyrin repeat protein, a novel class of engineered proteins, under investigation as a treatment of SARS-CoV-2 infection.

OBJECTIVE

To investigate if ensovibep, in addition to remdesivir and other standard care, improves clinical outcomes among patients hospitalized with COVID-19 compared with standard care alone.

DESIGN

Double-blind, randomized, placebo-controlled, clinical trial. (ClinicalTrials.gov: NCT04501978).

SETTING

Multinational, multicenter trial.

PARTICIPANTS

Adults hospitalized with COVID-19.

INTERVENTION

Intravenous ensovibep, 600 mg, or placebo.

MEASUREMENTS

Ensovibep was assessed for early futility on the basis of pulmonary ordinal scores at day 5. The primary outcome was time to sustained recovery through day 90, defined as 14 consecutive days at home or place of usual residence after hospital discharge. A composite safety outcome that included death, serious adverse events, end-organ disease, and serious infections was assessed through day 90.

RESULTS

An independent data and safety monitoring board recommended that enrollment be halted for early futility after 485 patients were randomly assigned and received an infusion of ensovibep (n = 247) or placebo (n = 238). The odds ratio (OR) for a more favorable pulmonary outcome in the ensovibep (vs. placebo) group at day 5 was 0.93 (95% CI, 0.67 to 1.30; P = 0.68; OR > 1 would favor ensovibep). The 90-day cumulative incidence of sustained recovery was 82% for ensovibep and 80% for placebo (subhazard ratio [sHR], 1.06 [CI, 0.88 to 1.28]; sHR > 1 would favor ensovibep). The primary composite safety outcome at day 90 occurred in 78 ensovibep participants (32%) and 70 placebo participants (29%) (HR, 1.07 [CI, 0.77 to 1.47]; HR < 1 would favor ensovibep).

LIMITATION

The trial was prematurely stopped because of futility, limiting power for the primary outcome.

CONCLUSION

Compared with placebo, ensovibep did not improve clinical outcomes for hospitalized participants with COVID-19 receiving standard care, including remdesivir; no safety concerns were identified.

PRIMARY FUNDING SOURCE

National Institutes of Health.

SARS-CoV-2 Rapid Antigen Testing of Symptomatic and Asymptomatic Individuals on the University of Arizona Campus

SARS-CoV-2, the cause of COVID19, has caused a pandemic that has infected more than 80 M and killed more than 1.6 M persons worldwide. In the US as of December 2020, it has infected more than 32 M people while causing more than 570,000 deaths. As the pandemic persists, there has been a public demand to reopen schools and university campuses. To consider these demands, it is necessary to rapidly identify those individuals infected with the virus and isolate them so that disease transmission can be stopped. In the present study, we examined the sensitivity of the Quidel Rapid Antigen test for use in screening both symptomatic and asymptomatic individuals at the University of Arizona from June to August 2020. A total of 885 symptomatic and 1551 asymptomatic subjects were assessed by antigen testing and real-time PCR testing. The sensitivity of the test for both symptomatic and asymptomatic persons was between 82 and 90%, with some caveats.

Orthogonal SARS-CoV-2 Serological Assays Enable Surveillance of Low-Prevalence Communities and Reveal Durable Humoral Immunity

We conducted a serological study to define correlates of immunity against SARS-CoV-2. Compared to those with mild coronavirus disease 2019 (COVID-19) cases, individuals with severe disease exhibited elevated virus-neutralizing titers and antibodies against the nucleocapsid (N) and the receptor binding domain (RBD) of the spike protein. Age and sex played lesser roles. All cases, including asymptomatic individuals, seroconverted by 2 weeks after PCR confirmation. Spike RBD and S2 and neutralizing antibodies remained detectable through 5-7 months after onset, whereas α-N titers diminished. Testing 5,882 members of the local community revealed only 1 sample with seroreactivity to both RBD and S2 that lacked neutralizing antibodies. This fidelity could not be achieved with either RBD or S2 alone. Thus, inclusion of multiple independent assays improved the accuracy of antibody tests in low-seroprevalence communities and revealed differences in antibody kinetics depending on the antigen. We conclude that neutralizing antibodies are stably produced for at least 5-7 months after SARS-CoV-2 infection.

Detection, prevalence, and duration of humoral responses to SARS-CoV-2 under conditions of limited population exposure

We conducted an extensive serological study to quantify population-level exposure and define correlates of immunity against SARS-CoV-2. We found that relative to mild COVID-19 cases, individuals with severe disease exhibited elevated authentic virus-neutralizing titers and antibody levels against nucleocapsid (N) and the receptor binding domain (RBD) and the S2 region of spike protein. Unlike disease severity, age and sex played lesser roles in serological responses. All cases, including asymptomatic individuals, seroconverted by 2 weeks post-PCR confirmation. RBD- and S2-specific and neutralizing antibody titers remained elevated and stable for at least 2-3 months post-onset, whereas those against N were more variable with rapid declines in many samples. Testing of 5882 self-recruited members of the local community demonstrated that 1.24% of individuals showed antibody reactivity to RBD. However, 18% (13/73) of these putative seropositive samples failed to neutralize authentic SARS-CoV-2 virus. Each of the neutralizing, but only 1 of the non-neutralizing samples, also displayed potent reactivity to S2. Thus, inclusion of multiple independent assays markedly improved the accuracy of antibody tests in low seroprevalence communities and revealed differences in antibody kinetics depending on the viral antigen. In contrast to other reports, we conclude that immunity is durable for at least several months after SARS-CoV-2 infection.

Core needle biopsy with endobronchial ultrasonography: single center experience with 100 cases

INTRODUCTION

Adequate sampling by endobronchial ultrasound (EBUS)-transbronchial needle aspiration to meet the demands of precision medicine or histologic evaluation is challenging. There is increasing demand for core biopsy specimens with advances in therapy. Franseen enodoscopic ultrasound needles have shown promising results in gastroenterology application for obtaining core biopsies and same design has recently been extended for pulmonary use. We evaluated Franseen needles with EBUS to assess its utility, safety and ability to provide core biopsy specimens.

MATERIALS AND METHODS

Retrospective analysis of our database at the University of Utah of patients undergoing EBUS with a Franseen needle was performed to ascertain the performance characteristics of this needle in the first 100 patients after its implementation. Medical records were also reviewed to identify any immediate procedure-related complications.

RESULTS

One hundred seventy locations were sampled in 100 patients. A total of 152 lymph nodes and 18 masses were sampled. Core biopsies, as per pathology report, were seen in 87% of patients. A clinically concordant pathological diagnosis was established in 97% of patients. Diagnostic yield for granulomatous lymphadenopathy was 95.6% (22 of 23). No patient-related adverse events were noted.

CONCLUSION

The Franseen needle evaluated in this study can safely procure core tissue samples during EBUS bronchoscopy that are adequate for histopathological diagnosis in benign and malignant lesions. Its ability to provide adequate tissue in patients with granulomatous inflammation is encouraging.

Renal replacement therapy in patients with acute respiratory distress syndrome: a single-center retrospective study

Background

Patients with acute respiratory distress syndrome (ARDS) who develop acute kidney injury have increased mortality and frequently require renal replacement therapy (RRT). The optimal timing for initiation of RRT after onset of ARDS to improve survival is not known.

Methods

We retrospectively reviewed clinical data on patients admitted to our health system over a 2-year period. Individual charts were carefully reviewed to ascertain that patients met the Berlin criteria for ARDS and to categorize RRT utilization. The Kaplan–Meier analysis was conducted to compare early (£48 hours postintubation) versus late (>48 hours postintubation) initiation of RRT. Associations between RRT initiation and mortality were evaluated using Cox proportional hazards regression.

Results

A total of 75 patients were identified with ARDS, 95% of whom received RRT. Mortality of patients who required RRT was 56%. The main indications for RRT initiation were fluid overload (75%), metabolic acidosis (64%), and hyperkalemia (33%). The Kaplan–Meier analysis comparing early initiation of RRT to late initiation of RRT showed no survival benefit. Cox proportional hazard models testing the association between timing of RRT initiation with survival and adjusting for sex, race, ethnicity, and Acute Physiology and Chronic Health Evaluation II score did not reach statistical significance (HR=0.94, 95% CI=0.48–1.86).

Conclusion

Timing of RRT initiation was not associated with a survival benefit. Prospective study in the utilization and outcomes of RRT in ARDS could assist in optimizing its usage in this population.

Reliability of quantitative sudomotor axon reflex testing and quantitative sensory testing in neuropathy of impaired glucose regulation

Reproducible neurophysiologic testing paradigms are critical for multicenter studies of neuropathy associated with impaired glucose regulation (IGR), yet the best methodologies and endpoints remain to be established. This study evaluates the reproducibility of neurophysiologic tests within a multicenter research setting. Twenty-three participants with neuropathy and IGR were recruited from two study sites. The reproducibility of quantitative sudomotor axon reflex test (QSART) and quantitative sensory test (QST) (using the CASE IV system) was determined in a subset of patients at two sessions, and it was calculated from intraclass correlation coefficients (ICCs). QST (cold detection threshold: ICC=0.80; vibration detection threshold: ICC=0.75) was more reproducible than QSART (ICC foot=0.52). The performance of multiple tests in one setting did not improve reproducibility of QST. QST reproducibility in our IGR patients was similar to reports of other studies. QSART reproducibility was significantly lower than QST. In this group of patients, the reproducibility of QSART was unacceptable for use as a secondary endpoint measure in clinical research trials.

The Utah Early Neuropathy Scale: a sensitive clinical scale for early sensory predominant neuropathy

Early neuropathy is often sensory predominant and prominently involves small-diameter nerve fibers. Established neuropathy examination scales such as the Michigan Diabetic Neuropathy Scale (MDNS) and the Neuropathy Impairment Score-Lower Leg (NIS-LL) focus primarily on large-fiber sensory and motor function. Here, we validate the Utah Early Neuropathy Scale (UENS), a physical examination scale specific to early sensory predominant polyneuropathy. Compared with other scales, the UENS emphasizes severity and spatial distribution of pin (sharp) sensation loss in the foot and leg and focuses less on motor weakness. UENS, MDNS, and NIS-LL were compared in 215 diabetic or prediabetic subjects, with (129) or without neuropathy (86), and repeated in 114 neuropathy subjects after 1 year of follow-up. Neuropathy severity was also evaluated with nerve conduction studies, quantitative sensory testing, quantitative sudomotor axonal reflex testing, and intraepidermal nerve fiber density determination. The UENS had a high degree of interrater reliability (interclass correlation of 94%). UENS correlated significantly to MDNS and NIS-LL (p < 0.01), and more significantly than MDNS or NIS-LL to confirmatory tests. In this cohort, UENS had a superior profile to receiver operating characteristic analysis across a range of scores, with a sensitivity (92%) higher than MDNS (67%) or NIS-LL (81%), without sacrificing specificity. UENS more closely correlated with change in ancillary and small-fiber neuropathy measures over 1 year follow-up than did MDNS or NIS-LL. UENS is a sensitive and reproducible clinical measure of sensory and small-fiber nerve injury and may be useful in trials of early neuropathy.

Lifestyle intervention for pre-diabetic neuropathy

OBJECTIVE

The purpose of this study was to evaluate intraepidermal nerve fiber density (IENFD) as a sensitive measure of neuropathy change in patients with neuropathy associated with impaired glucose tolerance (IGT) receiving lifestyle intervention based on that used in the Diabetes Prevention Program.

RESEARCH DESIGN AND METHODS

We performed 3-mm skin biopsies with measurement of IENFD at the distal leg and proximal thigh at baseline and after 1 year in 32 subjects with IGT. Each received individualized diet and exercise counseling as a standard of care. Nerve conduction studies, quantitative sensory testing, quantitative sudomotor axon reflex testing, and the Michigan Diabetic Neuropathy score were performed, and a visual analog pain scale was completed. Two-hour oral glucose tolerance tests (OGTTs) following the American Diabetes Association guidelines were performed, and serum lipid levels were measured at baseline and 1 year later.

RESULTS

Baseline distal IENFD was 0.9 +/- 1.2 fibers/mm and proximal IENFD was 4.8 +/- 2.3 fibers/mm. Baseline distal IENFD correlated with fasting glucose (P < 0.001) and OGTT (P < 0.01). After 1 year of treatment, there was a 0.3 +/- 1.1-fiber/mm improvement in distal IENFD and a 1.4 +/- 2.3-fiber/mm improvement in proximal IENFD (P < 0.004). The change in proximal IENFD correlated with decreased neuropathic pain (P < 0.05) and a change in sural sensory amplitude (P < 0.03).

CONCLUSIONS

These findings indicate that diet and exercise counseling for IGT results in cutaneous reinnervation and improved pain. Skin biopsy was the most sensitive measure of neuropathy change over 1 year. IENFD should be included as an end point in future neuropathy trials.