Ethics of college vaccine mandates, using reasonable comparisons.

In the paper 'COVID-19 vaccine boosters for young adults: a risk-benefit assessment and ethical analysis of mandate policies at universities,' Bardosh et al argued that college mandates of the COVID-19 booster vaccine are unethical. The authors came to this conclusion by performing three different sets of comparisons of benefits versus risks using referenced data and argued that the harm outweighs the risk in all three cases. In this response article, we argue that the authors frame their arguments by comparing values that are not scientifically or reasonably comparable and that the authors used values that represent grossly different risk profiles and grouped them into a set of figures to create an illusion of fair comparisons. We argue that absent the falsely skewed portrayals of a higher level of risk over benefit in their misrepresented figures, the five ethical arguments they presented completely fall apart.

Feasibility and acceptability of an online parenting intervention to address behaviour problems in moderately to extremely preterm pre-school and school-age children.

BACKGROUND: Preterm birth is associated with adverse mental health outcomes, including internalizing problems, social difficulties and inattention. Interventions are needed beyond infancy and toddlerhood to support children and their families. We examined the feasibility and acceptability of the I-InTERACT Preterm pilot study, an online parenting intervention for preterm children ages 3-8. METHOD: Families participated in a weekly intervention comprised of seven sessions with online modules followed by videoconference coaching sessions with a therapist. Following completion of the study, caregivers completed a survey to assess their satisfaction and were asked to participate in a voluntary semi-structured interview to provide feedback. We anticipated greater than a 50% participation rate (enrollment feasibility) and 75% completion rate (adherence feasibility). We also hypothesized that at least 80% of participants would be satisfied with the intervention (acceptability). RESULTS: Nineteen of 32 families (59%) enrolled in the study, suggesting adequate enrollment feasibility. Feasibility of programme completion (adherence) was lower than anticipated (59%). Regarding satisfaction, all caregivers agreed that the programme's information was relevant to them and their family. Nearly all participants (92%) indicated that they had a better understanding of the effects of preterm birth on behaviour, that they enjoyed the programme, that it met their expectations and that they recommend the programme to others. In qualitative interviews, caregivers expressed satisfaction with the content, skills they learned, and receiving direct coaching. Caregivers suggested improvements to increase intervention feasibility and skill implementation, including offering biweekly sessions and more hands-on coaching. CONCLUSION: Our largely satisfactory acceptability rates suggest the value of and need for a parenting intervention for children born preterm past the initial period of early development. Future directions include modifying the intervention in response to caregiver feedback to improve recruitment, engagement and adherence.

Antibody-mediated interferences affecting cardiac troponin assays: recommendations from the IFCC Committee on Clinical Applications of Cardiac Biomarkers.

The International Federation of Clinical Chemistry Committee on Clinical Applications of Cardiac Biomarkers (IFCC C-CB) provides educational documents to facilitate the interpretation and use of cardiac biomarkers in clinical laboratories and practice. Our aim is to improve the understanding of certain key analytical and clinical aspects of cardiac biomarkers and how these may interplay. Measurements of cardiac troponin (cTn) have a prominent place in the clinical work-up of patients with suspected acute coronary syndrome. It is therefore important that clinical laboratories know how to recognize and assess analytical issues. Two emerging analytical issues resulting in falsely high cTn concentrations, often several fold higher than the upper reference limit (URL), are antibody-mediated assay interference due to long-lived cTn-antibody complexes, called macrotroponin, and crosslinking antibodies that are frequently referred to as heterophilic antibodies. We provide an overview of antibody-mediated cTn assay interference and provide recommendations on how to confirm the interference and interpret the results.

Effect of Macrotroponin in a Cohort of Community Patients with Elevated Cardiac Troponin.

BACKGROUND: Macrotroponin is an important cause of discrepancy between current high-sensitivity cardiac troponin (hs-cTn) assays, however, its clinical significance is unclear. This study examined the effects of macrotroponin and repeat testing by different hs-cTnI assays in a cohort of community patients with elevated hs-cTnI. METHODS: The first residual serum specimen from each patient in the community admitted to hospital with elevated hs-cTnI (Siemens hs-cTnI Centaur) was retested after immunoglobulin depletion and by 5 other hs-cTn assays. Low recovery of cTnI (<40%) following immunoglobulin depletion was considered as macrotroponin. A retrospective chart review was performed for these participants. Investigator-adjudicated diagnosis served as the reference standard. RESULTS: In our cohort of community patients with elevated troponin (n = 188), participants with macrotroponin (n = 99) often had a multifactorial or indeterminate myocardial injury (56% vs 25%) and were less likely to have acute coronary syndrome (9% vs 28%). On repeat testing of cTn on other platforms, better diagnostic performance (c-statistics) for ischemic and non-ischemic cardiac causes was observed on the Beckman Access hs-cTnI (0.74; 95% confidence interval [CI] 0.67-0.81) or the Abbott hs-cTnI Architect (0.75; CI 0.68-0.82) compared to the Siemens hs-cTnI Vista (0.62; CI 0.54-0.70; P < 0.05). This could be attributed to differences in assay reactivity for macrotroponin. Interestingly, better diagnostic performance was observed in patients without macrotroponin. Although a small number of deaths occurred (n = 16), participants with macrotroponin had better overall survival. CONCLUSIONS: In the low-risk setting, the presence of macrotroponin was clinically associated with multifactorial or indeterminate causes of troponin elevation.

Identification of macrotroponin T: findings from a case report and non-reproducible troponin T results.

OBJECTIVES: Macrotroponin is due to cardiac troponin (cTn) binding to endogenous cTn autoantibodies. While previous studies showed a high incidence of macrotroponin affecting cTnI assays, reports of macrotroponin T, particularly without cTnI reactivity, have been rare. Although the clinical significance of macrotroponin is not fully understood, macroenzymes and complexes are recognised to cause confusion in interpretation of laboratory results. The potential for adverse clinical consequences due to misinterpretation of affected results is very high. METHODS: We describe four cases of macrotroponin T with persistently low high sensitivity cTnT (hs-cTnT) by the 9 min compared to the 18 min variant of the assay. Three cases were serendipitously identified due to the use of a lot number of Roche hs-cTnT affected by non-reproducible results, necessitating measurement of cTnT in duplicate. We identified and characterised these macrotroponin specimens by immunoglobulin depletion (Protein A and PEG precipitation), mixing studies with EDTA and recombinant cTnT. RESULTS: In cases of macro-cTnT, a lower result occurred on the hs-cTnT using the 9 min compared to 18 min variant assay (ratio of 9-18 min hs-cTnT <0.80). Mixing studies with recombinant cTnT or EDTA demonstrated a difference in recovery vs. controls. One of these patients demonstrated a high molecular weight complex for cTnI and cTnT demonstrating a macrocomplex involving both cTn. This patient demonstrated a rise and fall in cTn when measured by several commercial assays consistent with genuine acute cardiac injury. CONCLUSIONS: We identified several cases of macro-cTnT and described associated clinical and biochemical features.

Discrepancy between Cardiac Troponin Assays Due to Endogenous Antibodies.

BACKGROUND: Despite well-described analytical effects of autoantibodies against cardiac troponin (cTn) I on experimental assays, no study has systematically examined their impact on cTn assays in clinical use. We determined the effects of endogenous antibodies on 5 different cTnI assays and a cTnT assay. METHODS: cTn was measured by 6 methods: Siemens hs-cTnI Centaur, Siemens hs-cTnI Vista, Abbott hs-cTnI Architect, Beckman hs-cTnI Access, Beckman cTnI Access, and Roche hs-cTnT Elecsys. Measurements were repeated on 5 assays (all except Siemens hs-cTnI Vista) following immunoglobulin depletion by incubation with protein A. Low recovery of cTnI (<40%) following immunoglobulin depletion was considered positive for macro-cTnI. Protein A findings were validated by gel filtration chromatography and polyethylene glycol precipitation. RESULTS: In a sample of 223 specimens selected from a community laboratory that uses the Siemens hs-cTnI Centaur assay and from which cTn was requested, 76% of samples demonstrated increased cTnI (median, 88 ng/L; interquartile range, 62-204 ng/L). Macro-cTnI was observed in 123 (55%) of the 223 specimens. Comparisons of cTnI assays markedly improved once patients with macro-cTnI were removed. Passing-Bablok regression analysis between hs-cTnI assays demonstrated different slopes for patients with and without macro-cTnI. In patients with macro-cTnI, 89 (72%) showed no effect on the recovery of cTnT, whereas 34 (28%) had reduced recovery of cTnT. The proportion of results above the manufacturers' 99th percentile varied with the cTn assay and macro-cTnI status. CONCLUSION: We suggest that the observed discrepancy between hs-cTnI assays may be attributed in part to the presence of macro-cTnI.

Biochemical Differences Between Vitreous Humor and Cerebral Spinal Fluid in a Death From Diabetic Ketoacidosis.

Biochemical analysis of cerebrospinal fluid (CSF) and vitreous humor (VH) forms an important diagnostic ancillary test at autopsy. Cerebrospinal fluid can be sampled from the ventricular system (VA) and from lumbar puncture (LP), whereas VH can be sampled from the orbits. Biochemical electrolytes seem to vary between VH and CSF collected from different sites, but whether there is any difference in glucose and ß-hydroxybutyrate is unclear. We present a case report of a 21-year-old man who died of diabetic ketoacidosis confirmed at autopsy. Ventricular system, LP, and VH were biochemically analyzed and showed that glucose was highest in VH (41 mmol/L) and was 6 and 8 mmol/L higher than CSF in the LP and VA, respectively. ß-Hydroxybutyrate was also highest in VH (20 mmol/L) and was 5 and 6 mmol/L higher than LP and VA, respectively. Our findings suggest that postmortem CSF glucose and ß-hydroxybutyrate may not truly reflect that of VH and vary between CSF sampling sites.

Elevated Cerebrospinal Fluid Sodium and Chloride Levels in a Saltwater Drowning Death.

To ascribe a cause of death from drowning in a body immersed in water can be difficult because of the absence of specific postmortem findings and unreliable ancillary tests. Postmortem vitreous biochemical analysis is documented to be a useful adjunct ancillary test to aid the diagnosis of saltwater drowning. A major confounding factor in using postmortem vitreous is the effect of electrolyte diffusion and water osmosis during immersion. A recent animal study suggested that cerebrospinal fluid (CSF) biochemical analysis, which is unaffected by immersion, may be an alternative. However, to date, there are no human data to support this. We report a saltwater drowning death from presumed suicide in which the postmortem CSF sodium and chloride level was elevated compared with nonimmersion deaths. This case gives evidence to support the potential use of postmortem CSF sodium and chloride level as an adjunct to the diagnosis of saltwater drowning.

Postmortem Tryptase Level in 120 Consecutive Nonanaphylactic Deaths: Establishing a Reference Range as <23 µg/L.

Postmortem tryptase is a useful biochemical test to aid the diagnosis of anaphylaxis. Multiple perimortem and postmortem factors have been documented to cause an elevation in postmortem tryptase level. One factor that was recently recognized to have an impact on postmortem tryptase level is correct sampling technique. A recent study recommended aspirating blood samples from a clamped femoral/external iliac vein to be used for reliable postmortem tryptase analysis. This study sampled 120 consecutive nonanaphylactic deaths in which all the peripheral bloods were sampled as recommended. Postmortem interval, resuscitation, different nonanaphylactic causes of death, sex, and age did not show any statistical significant relation to postmortem tryptase level in Student t test, Pearson correlation, and univariate and multivariate analyses. The mean (SD) postmortem tryptase level was 8.4 (5.2) µg/L (minimum, 1.0 µg/L; maximum, 36.1 µg/L; median, 7.3 µg/L). Using nonparametric methods, the postmortem tryptase reference range in nonanaphylactic death was established as <23 µg/L (97.5th percentile).

Elevation of Postmortem Cerebrospinal Fluid Sodium and Chloride Levels Is a Potential Adjunct Test in the Diagnosis of Salt Water Drowning.

Postmortem vitreous humor biochemistry is a useful test in the diagnosis of salt water drowning (SWD). A significant limitation of vitreous humor is the potential effect of prolonged immersion. A recent animal study and case report suggested that cerebrospinal fluid biochemistry may be an alternative to vitreous because it is more resistant to the effects of immersion, given its protected anatomical location. This study compared postmortem cerebrospinal fluid sodium and chloride (PMCSC) levels collected via ventricular aspiration (PMCSC_V) and via lumbar puncture (PMCSC_L) in 13 SWD and 31 nonimmersion deaths. It showed a significant elevation in PMCSC levels in SWD deaths for both PMCSC_V and PMCSC_L (P < 0.05). The areas under the curve on the receiver operating characteristic curves for PMCSC_V and PMCSC_L were 0.73 and 0.83, respectively. The optimal cutoff for PMCSC_V was 216 mmol/L (sensitivity, 0.60; specificity, 0.72; likelihood ratio, 1.80; positive predictive value, 0.45) and for PMCSC_L was 241 mmol/L (sensitivity, 0.78; specificity, 0.73; likelihood ratio, 2.89; positive predictive value, 0.46). This study supports PMCSC levels as another biochemical test that can potentially aid in the diagnosis of SWD, particularly in cases where vitreous humor samples are unavailable or uninterpretable.

Combining Postmortem Vitreous Sodium and Chloride and Lung-Body Ratio in Aiding the Diagnosing Saltwater Drowning.

Diagnosing death due to drowning can be difficult, and several postmortem findings have been postulated to aid the diagnosis. Increased lung weights are often seen in drowning deaths. Lung-body (LB) ratio was described to be the best anatomical lung measurement in diagnosing drowning. Postmortem vitreous humor sodium and chloride (PMVSC) was reported to be a useful biochemical test in diagnosing saltwater drowning when the immersion time is less than 1 hour (SWD1). The presented study compared the diagnostic accuracies between LB ratio, PMVSC, and their combination in diagnosing SWD1 in 20 SWD1 and 50 nonimmersion deaths. Classification tree models were used for analysis and revealed that combination of PMVSC and LB ratio was most accurate in diagnosing SWD1 (misclassification rate, 4%), followed by PMVSC (misclassification rate, 10%) and LB ratio (misclassification rate, 24%). A quantifiable diagnostic improvement was established when both LB ratio and PMVSC were used. After adjusting for interlaboratory variations, the developed tree models can be a reliable way in aiding the diagnosis of SWD1.

The Potential Diagnostic Accuracy of Autopsy Lung Weights, Lung-Heart Ratio, and Lung-Body Ratio in Drowning Deaths.

Lung weights are often increased in drowning deaths as well as in other types of deaths. Lung weights may also vary with age, sex, and body weight. A variety of methods have been proposed to utilize lung weight data to assist with the diagnosis of drowning. The present study compared lung weight, lung-heart ratio (LH), and lung-body ratio (LB) between 50 consecutive drowning and 50 nonimmersion deaths in order to assess the accuracy in diagnosing drowning. Analysis revealed both LH and LB to be statistically higher in drowning deaths (P < 0.05), with LB being the most robust measurement. However, the overall diagnostic accuracies of lung weight, LH, and LB were poor to fair, and should therefore be used only in conjunction with the other diagnostic criteria.

Postmortem Vitreous Sodium and Chloride Elevate After 1 Hour and Magnesium After 2 Hours in Bovine Eyeballs Immersed in Salt Water.

BACKGROUND: Postmortem vitreous sodium (Na) and chloride (Cl) are good ancillary tests in diagnosing salt-water drowning. Vitreous Na and Cl appear to elevate from salt-water drowning and immersion, whereas vitreous magnesium (Mg) appears to be unaffected by drowning, but elevates from immersion. The relative changes of these electrolytes during salt-water immersion are unknown, particularly with shorter immersion times. Understanding the relative changes may aid in the interpretation of vitreous electrolytes in bodies recovered from salt water. AIM: The aim of this study was to compare the changes of vitreous Na, Cl, and Mg when immersed in salt water. METHODS: Bovine eyeballs were randomized into 2 groups (submerged in salt water and control). The vitreous Na, Cl, and Mg from 6 eyeballs were measured from each group (without replacement) at 1, 2, 4, and 6 hours. RESULTS: There were no statistically significant elevations in bovine vitreous Na and Cl for up to 1 hour and vitreous Mg for up to 2 hours. CONCLUSIONS: Bovine vitreous Na and Cl elevate earlier than Mg when immersed in salt water. Assuming similar physical properties, an elevation in vitreous Mg in bodies immersed in salt water indicates the immersion effects of causing raised vitreous Na and Cl have started.

Differences in Sampling Site on Postmortem Cerebrospinal Fluid Biochemistry: A Preliminary Study.

Cerebrospinal fluid (CSF) is often analyzed at postmortem. The presented preliminary study compared postmortem CSF samples for biochemical analysis from the subarachnoid space around the spinal cord and ventricular space of the brain. This study compared 15 paired CSF samples in which the CSF from the subarachnoid space via lumbar puncture had higher sodium and chloride levels and lower magnesium and potassium levels than CSF from the ventricles. The differences correlated significantly with the deceased's age and had a similar trend with postmortem interval. This study suggests that CSF from different collection sites has different electrolyte concentrations, which are age and possibly postmortem interval dependent. When collecting CSF, the pathologist should document the collection site, age, and postmortem interval, and the mixing of CSF samples from different sites should be avoided. Further studies are warranted to clarify other possible reasons to explain the observed differences.

Utilization of Reflex Testing for Direct Bilirubin in the Early Recognition of Biliary Atresia.

BACKGROUND: Delayed diagnosis of biliary atresia is an important cause of pediatric end-stage liver failure and liver transplantation. We sought to determine whether direct bilirubin is underutilized by retrospectively reviewing patients with biliary atresia. Further, we aimed to determine the role of reflex testing for direct bilirubin in patients suspected for jaundice. METHODS: The time intervals between total bilirubin and direct bilirubin measurements were retrospectively reviewed in patients with biliary atresia. We also audited the results of two major laboratories that had implemented reflex testing for direct bilirubin. We evaluated the clinical impact and cost of reflex testing in infants with increased direct bilirubin (>1.5 mg/dL; >25 µmol/L). RESULTS: In patients with known biliary atresia, an isolated total bilirubin measurement preceded direct bilirubin measurement in 46% (40/87) of patients; with a median delay of 19 days (interquartile range 3-44 days). In the community setting, direct bilirubin had a higher clinical specificity for biliary atresia than in the hospital setting. Reporting direct bilirubin results in 1591 infants younger than 2 weeks of age in the community was associated with three admissions to the hospital, one of whom was diagnosed with biliary atresia. The cost for the two laboratories for direct-bilirubin testing was estimated at US$3200 (NZ$4600) for each newly diagnosed case of biliary atresia. CONCLUSIONS: We identified underutilization of direct bilirubin as a cause of delay in the recognition of biliary atresia and show that reflex testing for direct bilirubin in jaundiced infants is a cost-effective solution.

The modulation of the phosphorylation status of NKCC1 in organ cultured bovine lenses: Implications for the regulation of fiber cell and overall lens volume.

In previous work, we have shown the Sodium/Potassium/2 Chloride Cotransporter (NKCC1) to be a key effector of lens fiber cell volume regulation. Since others have shown that the activity of NKCC1 is regulated via its phosphorylation status, the purpose of this study was to investigate whether NKCC1 phosphorylation can be modulated in organ cultured bovine lenses, and to see how this relates to changes in lens wet weight. Western blotting was first used to confirm the expression of NKCC1, phosphorylated NKCC1 (NKCC1-P) and the regulatory kinases WNK/SPAK and phosphatases PP1/PP2A in bovine lenses at the protein level. Changes to NKCC1-P status were then assessed by organ culturing bovine lenses in either isotonic, hypertonic or hypotonic solutions in the presence or absence of the NKCC inhibitor, bumetanide, or phosphatase inhibitors okadaic acid and calyculin A. After 1-22 h of culturing, lenses were weighed, assessed for transparency and the cortical protein fractions analyzed by western blot using antibodies to detect total NKCC1 and NKCC1-P. NKCC1, NKCC1-P, SPAK, PP1 and PP2A were all detected in the membrane fraction of bovine lenses. Under hypertonic conditions, NKCC1 is phosphorylated and activated to mediate a regulatory volume increase. Finally, NKCC1-P signal increased in the presence of phosphatase inhibitors indicating that PP1/PP2A can dephosphorylate NKCC1. These results show that the phosphorylation status and hence activity of NKCC1 is dynamically regulated and that in response to hypertonic stress, NKCC1 activity is increased to effect a regulatory volume increase that limits cell shrinkage. These findings support the view that the lens dynamically regulates ion fluxes to maintain steady state lens volume, and suggest that dysfunction of this regulation maybe an initiating factor in the localized fiber cell swelling that is a characteristic of diabetic lens cataract.

Practical approaches to the detection of macrotroponin.

INTRODUCTION: Macrotroponin is increasingly recognised as a cause of confusion in interpreting high-sensitivity cardiac troponin (hs-cTnI) results. In this study, we sought to evaluate two practical approaches to detecting macrotroponin. These two approaches are PEG precipitation and SVM (support vector machine) analysis to classify discrepancies between hs-cTn assays. METHOD: Residual serum and heparin plasma specimens (n = 483) with initially elevated hs-cTnI from hospital and community laboratories were retested on multiple hs-cTn platforms before and after PEG precipitation and Protein A immunoglobulin depletion. SVM analysis was conducted to identify a linear equation that best discriminated specimens with macrotroponin using a combination of results from two different hs-cTn assays. FINDINGS: The diagnostic performance of PEG precipitation was carried out using Protein A immunoglobulin depletion as the reference comparator. When a cutoff residual activity after PEG precipitation of ≤ 20% was used, this threshold carried a high specificity of 92% (confidence interval 83-98%; n = 189) using the Siemens hs-cTnI Vista assay and 95% specificity (86%-98%; n = 242) using the Abbott hs-cTnI Architect assay. SVM analysis generated a linear equation identifying macrotroponin specimens from results obtained on two hs-cTn assays. This approach can be highly specific, comparable to PEG precipitation when certain assay combinations and concentrations are used. CONCLUSION: We describe and identify practical alternatives to detecting macrotroponin. These approaches can be optimised for high specificity, reducing the need for more complex laboratory methods.

Molecular identification and cellular localization of a potential transport system involved in cystine/cysteine uptake in human lenses.

In this study we have sought to identify whether cystine uptake mechanisms previously identified in the rat lens are also found in the human lens. Using a combination of reverse transcriptase PCR, Western blotting and immunohistochemistry, we show that the light chain subunit of the cystine/glutamate exchanger (XC-), xCT, and members of the glutamate transporter family (XAG) which include the Excitatory Amino Acid Transporter 4 (EAAT4) and the Alanine Serine Cysteine Transporter 2 (ASCT2) are all present at the transcript and protein level in human lenses. We demonstrate that in young lenses xCT, EAAT4 and ASCT2 are expressed in all regions indicating that a potential cystine uptake pathway similar to that found in the rat might also exist in human lenses. However, with increasing age, the immunolabeling for all transporters decreases, with no xCT labelling detected in the centre of old donor lenses. Our results show that XC- and EAAT4/ASCT2 may work together to mediate cystine uptake in the lens core of young human lenses. This suggests that the lens contains uptake mechanisms that are capable of accumulating cystine/cysteine in the lens centre where cysteine can be used as an antioxidant or cystine utilised as a source for protein-S-S-cysteine (PSSC) formation to buffer against oxidative stress. With increasing age, transporters in the lens core undergo age dependent post translational modifications. However, despite processing of these transporters with age, our results indicate that this cystine uptake pathway could account for the increased PSSC levels previously observed in the nucleus of older human lenses.