Point of care blood glucose devices in the hospital setting.

Dysglycemia is common among hospitalized patients. Accurate point-of-care (POC) glucose monitoring is necessary for the safe administration of insulin. Unfortunately, POC glucose meters are not all created equal. Interfering factors such as abnormal hematocrit, abnormal oxygen tension, and oxidizing/reducing substances can lead to inaccurate glucose measurements and result in inappropriate insulin dosing. The introduction of autocorrecting glucose meters has changed the POC testing landscape. Autocorrecting glucose meters provide more accurate measurements and have been associated with improved glycemic control in hospitalized patients. Continuous glucose monitoring has also created interest in using these platforms in at-risk inpatient populations. Future glucose monitoring technologies such as artificial intelligence/machine learning, wearable smart devices, and closed-loop insulin management systems are poised to transform glycemic management. The goal of this review is to provide an overview of glucose monitoring technology, summarize the clinical impact of glucose monitoring accuracy, and highlight emerging and future POC glucose monitoring technologies.

Comparative performance of COVID-19 serology testing.

Background: The 2019 novel coronavirus infectious disease (COVID-19) pandemic resulted in a surge of assays aimed at detecting severe acute respiratory syndrome (SARS) - coronavirus (CoV) - 2 infection and prior exposure. Although both molecular and antigen testing have clearly defined uses, the utility of serology remains uncertain and is presently not recommended for assessing immunity. Methods: We conducted a pragmatic, observational study evaluating four commercially available emergency use authorized laboratory-based COVID-19 serology assays (Assays A-D). Remnant samples from hospitalized, and non-hospitalized SARS-CoV-2 PCR positive patients, as well as vaccinated and unvaccinated individuals were collected and tested. Positive percent agreement (PPA) and negative percent agreement (NPA) were calculated. Antibody concentrations were compared across the platforms and populations. Results: A total of 588 remnant samples derived from 500 patients were tested. PPA at 5-12 weeks post-PCR positive results for Assays A-D was 98.3, 97.4, 99.2, and 95.8% respectively. NPA was 100% across all platforms. Mean antibody concentrations at 2-4 weeks post-PCR positive result were significantly higher in hospitalized versus non-hospitalized patients, respectively, for Assay A (131.8 [101.7] vs. 95.6 [100.3] AU/mL, P < 0.001), B (61.7 [62.4] vs. 38.1 [40.5] AU/mL, P < 0.001), and C (157.6 [105.3] vs. 133.3 [100.7] AU/mL, P < 0.001). For individuals receiving two vaccine doses mean antibody concentrations were respectively 169.6 (104.4), 27.3 (50.8), 189.6 (120.9), 21.19 (13.1) AU/mL for Assays A-D. Conclusions: Overall, PPA and NPA differed across the four assays. Assays A and C produced higher PPA and NPA and detected larger concentrations of antibodies following vaccination.

The prevalence of elevated biotin in patient cohorts presenting for routine endocrinology, sepsis, and infectious disease testing.

Elevated blood biotin levels may interfere with some biotin-streptavidin immunoassays, used in clinical laboratories to aid diagnosis. The objective of this study was to determine the prevalence of elevated blood biotin levels in three at risk patient cohorts, where misclassification of disease status would have a high clinical impact. This retrospective, single-center study screened residual, de-identified plasma samples (N = 700) from adult patients undergoing routine thyroid stimulating hormone (TSH) (n = 500), procalcitonin (PCT) (n = 100), or human immunodeficiency virus (HIV) (n = 100) testing using the Elecsys® BRAHMS PCT (Roche Diagnostics), Access TSH (3rd IS) (Beckman Coulter Inc), and ARCHITECT HIV Ag/Ab Combo (Abbott Laboratories) immunoassays, respectively, for elevated levels of biotin (quantified by gas chromatography-time of flight mass spectrometry). Patients taking biotin supplements were included and dosages recorded from medical records. In the overall study cohort, blood biotin levels ranged 0.1-21.3 ng/mL; 44.3% (310/700) of samples were < 1 ng/mL, 54.7% (383/700) were 1-<10 ng/mL, and 1% (7/700) were ≥ 10 ng/mL. The sub-cohorts had similar ranges of biotin levels: 0.5-21.3 ng/mL (TSH), 0.1-12.1 ng/mL (PCT), and 0.3-7.3 ng/mL (HIV). In the 44 patients (6.3% of overall study cohort) who were documented as taking biotin supplements (range of doses, 2.5-10 mg/day), blood biotin levels ranged 0.9-21.3 ng/mL; 2.3% (1/44) of samples were < 1 ng/mL, 86.4% (38/44) were 1-<10 ng/mL, and 11.4% (5/44) were ≥ 10 ng/mL. Most patients who reported taking biotin supplements had blood biotin levels ≥ 1 ng/mL and the highest blood biotin level detected was 21.3 ng/mL.

A Multicenter Evaluation of a Point-of-Care Blood Glucose Meter System in Critically Ill Patients.

BACKGROUND: Our purpose was to evaluate the performance of the ACCU-CHEK® Inform II blood glucose monitoring system (Roche Diagnostics GmbH) compared with the perchloric acid hexokinase (PCA-HK) comparator method on the cobas® 6000 analyzer (Roche Diagnostics International Ltd) in critically ill patients. METHODS: Overall, 476 arterial (376 pediatric/adult, 100 neonate), 375 venous, and 100 neonatal heel-stick whole-blood samples were collected and evaluated from critical care settings at 10 US hospitals, including the emergency department, medical and surgical intensive care units (ICUs), and neonatal and pediatric ICUs. The ACCU-CHEK Inform II system was evaluated at 2 cutoff boundaries: boundary 1 was ≥95% of results within ±12 mg/dL of the reference (samples with blood glucose <75 mg/dL) or ±12% of the reference (glucose ≥75 mg/dL), and boundary 2 was ≥98% of results within ±15 mg/dL or ±15% of the reference. Clinical performance was assessed by evaluating sample data using Parkes error grid, Monte Carlo simulation, and sensitivity and specificity analyses to estimate clinical accuracy and implications for insulin dosing when using the ACCU-CHEK Inform II system. RESULTS: Proportions of results within evaluation boundaries 1 and 2, respectively, were 96% and 98% for venous samples, 94% and 97% for pediatric and adult arterial samples, 84% and 98% for neonatal arterial samples, and 96% and 100% for neonatal heel-stick samples. Clinical evaluation demonstrated high specificity and sensitivity, with low risk of potential insulin-dosing errors. CONCLUSIONS: The ACCU-CHEK Inform II system demonstrated clinically acceptable performance against the PCA-HK reference method for blood glucose monitoring in a diverse population of critically ill patients in US care settings.

Clinical Performance of the Point-of-Care cobas Liat for Detection of SARS-CoV-2 in 20 Minutes: a Multicenter Study.

Highly accurate testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at the point of care (POC) is an unmet diagnostic need in emergency care and time-sensitive outpatient care settings. Reverse transcription-PCR (RT-PCR) technology is the gold standard for SARS-CoV-2 diagnostics. We performed a multisite U.S. study comparing the clinical performance of the first U.S. Food and Drug Administration (FDA)-authorized POC RT-PCR for detection of SARS-CoV-2 in 20 min, the cobas Liat SARS-CoV-2 and influenza A/B nucleic acid test, to the most widely used RT-PCR laboratory test, the cobas 68/8800 SARS-CoV-2 test. Clinical nasopharyngeal swab specimens from 444 patients with 357 evaluable specimens at five U.S. clinical laboratories were enrolled from 21 September 2020 to 23 October 2020. The overall agreement between the Liat and 68/8800 systems for SARS-CoV-2 diagnostics was 98.6% (352/357). Using Liat, positive percent agreement for SARS-CoV-2 was 100% (162/162) and the negative percent agreement was 97.4% (190/195). The Liat is an RT-PCR POC test that provides highly accurate SARS-CoV-2 results in 20 min with performance equivalent to that of high-throughput laboratory molecular testing. Rapid RT-PCR testing at the POC can enable more timely infection control and individual care decisions for coronavirus disease 2019.

Diagnostic Reclassification by a High-Sensitivity Cardiac Troponin Assay.

STUDY OBJECTIVE: Our objective is to describe the rates of diagnostic reclassification between conventional cardiac troponin I (cTnI) and high-sensitivity cardiac troponin T (hs-cTnT) and between combined and sex-specific hs-cTnT thresholds in adult emergency department (ED) patients in the United States. METHODS: We conducted a prospective, single-center, before-and-after, observational study of ED patients aged 18 years or older undergoing single or serial cardiac troponin testing in the ED for any reason before and after hs-cTnT implementation. Conventional cTnI and hs-cTnT results were obtained from a laboratory quality assurance database. Combined and sex-specific thresholds were the published 99th percentile upper reference limits for each assay. Cases underwent physician adjudication using the Fourth Universal Definition of Myocardial Infarction. Diagnostic reclassification occurred when a patient received a diagnosis of myocardial infarction or myocardial injury with one assay but not the other assay. Our primary outcome was diagnostic reclassification between the conventional cTnI and hs-cTnT assays. Diagnostic reclassification probabilities were assessed with sample proportions and 95% confidence intervals for binomial data. RESULTS: We studied 1,016 patients (506 men [50%]; median age 60 years [25th, 75th percentiles 49, 71]). Between the conventional cTnI and hs-cTnT assays, 6 patients (0.6%; 95% confidence interval 0.2% to 1.3%) underwent diagnostic reclassification regarding myocardial infarction (5/6 reclassified as no myocardial infarction) and 166 patients (16%; 95% confidence interval 14% to 19%) underwent diagnostic reclassification regarding myocardial injury (154/166 reclassified as having myocardial injury) by hs-cTnT. CONCLUSION: Compared with conventional cTnI, the hs-cTnT assay resulted in no clinically relevant change in myocardial infarction diagnoses but substantially more myocardial injury diagnoses.