Limited Contribution of Creatine Kinase-Myocardial Band Alongside High-Sensitivity Cardiac Troponin in Diagnosing Acute Myocardial Infarction in an Emergency Department.

Cardiac biomarkers, especially high-sensitivity cardiac troponin C or I (hs-cTnC or hs-cTnI, respectively), are vital for diagnosing acute myocardial infarction (AMI). Despite the specificity of hs-cTn as a biomarker, the creatine kinase-myocardial band (CK-MB) is commonly used alongside hs-cTn in emergency departments (EDs). We analyzed 23,771 simultaneous hs-cTn (hs-cTnT or hs-cTnI) and CK-MB requests for 17,185 patients in tertiary hospital ED in 2022. The objective of this study was to assess their practical value in diagnosing AMI in real-world settings. Among all 17,185 patients tested, 98.0% underwent hs-cTnT and CK-MB tests, and substantially fewer underwent hs-cTnI testing. We observed concordance between the initial hs-cTn and CK-MB results in 71.3% of patients. Of 131 AMI cases, 57 were positive for both biomarkers, 63 for hs-cTn only, and none for CK-MB alone. CK-MB positivity was often found in the absence of AMI. Discrepancies between the hs-cTnT and hs-cTnI results occurred in 30.0% of patients. Indiscriminate CK-MB testing for diagnosing AMI in EDs should be reconsidered. Efficient use of CK-MB is important for reducing costs and ensuring optimal patient care.

Comparative analysis of the quantitative point-of-care CareSTART™ total bilirubin with central laboratory total bilirubin assays in neonatal blood samples.

This study aimed to assess and compare the accuracy of point-of-care CareSTART™ S1 Total Bilirubin test with a central laboratory total bilirubin assay using neonatal samples. This study was conducted using 152 paired measurements obtained from 122 neonates admitted to the neonatal intensive care unit. Total serum bilirubin (TSB) levels assayed with the central laboratory assay, laboratory bilirubinomter, trancutaneous bliribubin (TcB) instrument and CareSTART were compared using Bland-Altman analysis. The mean difference between the CareSTART and TSB values was -1.43 mg/dL and the 95% limit of agreement (LoA) was -4.25 to 1.39 mg/dL. CareSTART tended to underestimate total bilirubin concentrations compared with TcB, however, the LoA was narrower due to the smaller SD of mean difference for CareSTART. The CareSTART Total Bilirubin test provides an accurate alternative to TcB for total serum bilirubin measurement. Given its low-cost, ease-of-use, and portability, the use of CareSTART is expected to provide point-of-care measurements, especially in low-resource settings.

A comprehensive Exdia TRF-LFIA for simultaneous quantification of GFAP and NT-proBNP in distinguishing ischemic and hemorrhagic stroke.

The goal of this study is to create a highly sensitive time-resolved fluorescence lateral flow immunoassay (TRF-LFIA) capable of concurrently measuring glial fibrillary acidic protein (GFAP) and the N-terminal fragment of B-type natriuretic peptide precursor (NT-proBNP). This assay is designed as a diagnostic tool and aims to provide an algorithm for stroke management, specifically for distinguishing between Ischemic stroke (IS) and Hemorrhagic stroke (HS). However, LFIA to quantify simultaneous serum NT-proBNP and GFAP are not yet available. We have developed and validated a novel TRF-LFIA for the simultaneous quantitative detection of NT-proBNP and GFAP. The sensitivity and reproducibility of the immunoassay were significantly improved by employing specific monoclonal antibodies linked to europium nanoparticles (EuNPs) that specifically target NT-proBNP and GFAP. The detection area on the nitrocellulose membrane featured sandwich-style complexes containing two test lines for NT-proBNP and GFAP, and one Control line. The fluorescence intensity of these test lines and control line was measured using an in-house developed Exdia TRF-Plus analyzer. As proof-of-concept, we enrolled patients suspected of having a stroke who were admitted within a specific time frame (6 h). A small amount of clinical specimen (serum) was used. To optimize the LFIA, an EuNPs conjugated antibodies were investigated to improve the detection sensitivity and decrease the background signal as well shorten the detection time. The Exdia TRF-LFIA cartridge offers a wide linear dynamic detection range, rapid detection, high sensitivity, and specificity. The limit of detection was determined to be 98 pg/mL for NT-proBNP and 68 pg/mL for GFAP, with minimal cross-reactivity. There were 200 clinical human serum samples that were used to evaluate this platform with high correlation. By combining the results of NT-proBNP and GFAP, we formulated an algorithm for the clinical assessment of Ischemic Stroke (IS) and Hemorrhagic Stroke (HS). According to our proposed algorithm, the combination of GFAP and NT-proBNP emerged as the most effective biomarker combination for distinguishing between IS and HS. Exdia TRF-LFIA shows great potential as a supplemental method for in vitro diagnostics in the laboratory or in other point-of-care testing (POCT) applications. Its development substantially decreases the diagnosis time for IS and HS. The proposed algorithm not only minimizes treatment delays but also lowers medical costs for patients.