Performance of the Siemens' thyroid stimulating immunoglobulin assay in the diagnosis of hyperthyroidism: Prospective cohort study.

Background: Auto-antibody testing is recommended for Graves' Disease (GD). The thyroid-stimulating-immunoglobulin (TSI) bridge method is designed to provide specificity for stimulatory antibodies to the TSH receptor which may translate to differences in performance in diagnosis of GD compared to TSH-receptor-antibody (TRAb) assays that don't distinguish between TSH-receptor antibody subclasses. The objective of this study was to prospectively compare the performance of a TSI assay to a TRAb assay for diagnosis of GD.

Outcomes among adult recipients of CAR T-cell therapy for Burkitt lymphoma.

Burkitt lymphoma (BL) is an aggressive B-cell lymphoma that is associated with poor outcomes in patients with relapsed/refractory disease. This multicenter, retrospective study evaluated real-world CD19 chimeric antigen receptor (CAR) T-cell therapy outcomes in patients with relapsed/refractory BL using data abstracted from the medical records. In total, 31 patients received CAR T cells after a median of 3 previous therapies (range, 1-6).

Clinical Outcomes and Toxicity in Older Adults Receiving Chimeric Antigen Receptor T Cell Therapy.

Chimeric antigen receptor T cell therapy (CAR-T) has transformed the treatment landscape for adults with relapsed/refractory hematologic malignancies, but few studies have examined outcomes in older adults. We aimed to evaluate clinical outcomes and treatment toxicity in older adults receiving CAR-T for hematologic malignancies and to describe outcomes and toxicities in older adults age 75+ years compared to those age 65 to 74 years. We conducted a retrospective analysis of 141 adult patients age 65+ years (46.

Clinical efficacy and safety of chimeric antigen receptor T-cell therapy for mantle cell lymphoma with secondary central nervous system involvement.

Data describing outcomes of chimeric antigen receptor (CAR) T-cell therapy in patients with secondary central nervous system (SCNS) involvement of mantle cell lymphoma (MCL) are limited. We identified 10 patients with MCL and SCNS involvement treated with anti-CD19 CAR T-cell therapy at three US academic centres. Frequent objective responses were observed in the CNS (86%) and systemically (90%), and the 1-year progression-free survival was 47%.

Antimicrobial stewardship, procalcitonin testing, and rapid blood-culture identification to optimize sepsis care in critically ill adult patients: A quality improvement initiative.

We examined the effect of an antimicrobial stewardship program (ASP), procalcitonin testing and rapid blood-culture identification on hospital mortality in a prospective quality improvement project in critically ill septic adults. Secondarily, we have reported antimicrobial guideline concordance, acceptance of ASP interventions, and antimicrobial and health-resource utilization.

Chemotherapy-induced reversal of ciltacabtagene autoleucel-associated movement and neurocognitive toxicity.

In 2 complementary Letters to Blood, Karschnia et al and Graham et al provide new insights into the neurological toxicities that are observed with B-cell maturation antigen–directed chimeric antigen receptor T-cell treatment for multiple myeloma, identifying a frequency of immune effector cell–associated neurotoxicity syndrome (ICANS) that exceeds 40%. Severe ICANS is identified in 8% of patients in this real-world series. Outcomes were generally favorable, although the authors describe rare, late Parkinsonism-like hypokinetic movement disorders (also known as movement and neurocognitive toxicities) post-ICANS in 2 patients.

Updated reference intervals for urine normetanephrine have no effect on test sensitivity but fewer false positives.

Objective: We previously highlighted the problem of frequent false positives in 24 h urine normetanephrine(UNM) measurements owing to reference intervals that are inappropriately low for the population being screened for pheochromocytoma. Using a large population database, we devised new age-stratified reference intervals for the 24 h UNM test that were higher compared to previous. However, it was uncertain as to whether this would compromise test sensitivity for true pheochromocytoma cases.

5-Fluorouracil associated neurovascular toxicities.

Fluorouracil (5-FU) is a commonly used chemotherapeutic agent in many cancers. The widely reported adverse effects are infusion reactions, rash, fever, nausea, vomiting, peripheral neuropathy, and hepatic injury. However, there are limited data about its neurological side effects.

Inpatient Measurements of Urine Metanephrines are Indistinguishable from Pheochromocytoma: Retrospective Cohort Study.

Background: Pheochromocytoma is a rare cause of acute cardiovascular disease; however, any severe illness may have high catecholamines, simulating pheochromocytoma. We determined the spectrum of urine metanephrines from inpatient and outpatient collections without pheochromocytoma, compared with confirmed pheochromocytoma patients.

Methods: Retrospective analysis using centralized laboratory data serving all outpatients and hospitals in southern Alberta.

Properly Collected Plasma Metanephrines Excludes PPGL After False-Positive Screening Tests.

Context: False-positive results are common for pheochromocytoma/paraganglioma (PPGL) real-world screening.

Objective: Determine the correlation between screening urine and seated plasma metanephrines in outpatients where PPGL was absent, compared to meticulously prepared and supine-collected plasma metanephrines with age-adjusted references.

Design: Retrospective cohort study.

Moderate renal impairment does not preclude the accuracy of 24-hour urine normetanephrine measurements for suspected pheochromoctyoma.

Objective: A 24-hour urine nor/metanephrine (urine NM-MN) measurements are a recommended first step in pheochromocytoma diagnosis. We hypothesized the presence of renal impairment (CKD) significantly confounds the results obtained in a urine NM-MN collection, giving artificially lower measurements.

Design: Retrospective review of a comprehensive laboratory database with all urine NM-MN results from Southern Alberta from 2010 to 2018 (n = 15 505).

Multi-platform analytical evaluation of the Beckman Coulter Access high-sensitivity troponin I assay across different laboratory sites using Barricor plasma.

Objectives: Previous analytical evaluations of the Beckman Coulter Access high sensitivity troponin (hsTn) I assay have focused on single platforms and laboratory sites. The purpose of this study was to determine assay robustness across different platforms at multiple sites, platform-specific characteristics, and equivalence to other hsTn methods in a large laboratory network.

Methods: Barricor plasma was used to assess imprecision, linearity, sensitivity (limit of blank and detection, LOB/LOD), and comparability to the conventional AccuTnI+3 and other hsTn assays.

Five-Year Two-Center Retrospective Comparison of Central Laboratory Glucose to GEM 4000 and ABL 800 Blood Glucose: Demonstrating the (In)adequacy of Blood Gas Glucose.

Purpose: To evaluate the glucose assays of two blood gas analyzers (BGAs) in intensive care unit (ICU) patients by comparing ICU BGA glucoses to central laboratory (CL) glucoses of almost simultaneously drawn specimens.

Methods: Data repositories provided five years of ICU BGA glucoses and contemporaneously drawn CL glucoses from a Calgary, Alberta ICU equipped with IL GEM 4000 and CL Roche Cobas 8000-C702, and an Edmonton, Alberta ICU equipped with Radiometer ABL 800 and CL Beckman-Coulter DxC. Blood glucose analyzer and CL glucose differences were evaluated if they were both drawn either within ±15 or ±5 minutes.

Best practices in mitigating the risk of biotin interference with laboratory testing.

Dietary biotin intake does not typically result in blood biotin concentrations that exceed interference thresholds for in vitro diagnostic tests. However, recent trends of high-dose biotin supplements and clinical trials of very high biotin doses for patients with multiple sclerosis have increased concerns about biotin interference with immunoassays. Estimates of the prevalence of high biotin intake vary, and patients may be unaware that they are taking biotin.

A high rate of modestly elevated plasma normetanephrine in a population referred for suspected PPGL when measured in a seated position.

Objective: Determine rate of high plasma normetanephrine or metanephrine (PNM-PMN) in a large sample of patients according to PNM-PMN posture and age-adjusted references.

Design: Retrospective re-analysis of PNM-PMN from a Canadian reference laboratory (n = 5452), 2011-2015; most were in seated position (n = 5112) rather than supine (n = 340). An international PPGL database demonstrated expected distribution of supine PNM-PMN in PPGL patients.

Isocitrate dehydrogenase 1 and 2 mutations, 2-hydroxyglutarate levels, and response to standard chemotherapy for patients with newly diagnosed acute myeloid leukemia.

Background: Acute myeloid leukemia (AML) cells harboring mutations in isocitrate dehydrogenase 1 (IDH1) and isocitrate dehydrogenase 2 (IDH2) produce the oncometabolite 2-hydroxyglutarate (2HG). This study prospectively evaluated the 2HG levels, IDH1/2 mutational status, and outcomes of patients receiving standard chemotherapy for newly diagnosed AML.

Methods: Serial samples of serum, urine, and bone marrow aspirates were collected from patients newly diagnosed with AML, and 2HG levels were measured with mass spectrometry.

Concordance between laboratories in metal ion testing in patients with metal-on-metal hip implants.

Background: Testing of whole blood or serum metal ion levels has become an important part of assessing and monitoring the performance of metal-on-metal bearings, both in hip resurfacing arthroplasty and in total hip replacement. The aim of this study was to determine the concordance between 2 laboratories testing cobalt and chromium ion levels in patients with metal-on-metal bearings.

Methods: Serum and whole blood samples from patients who had undergone metal-on-metal resurfacing or large-diameter total hip arthroplasty were tested for cobalt and chromium ions in laboratory A (a recognized laboratory) and laboratory B (tasked with testing clinical specimens).

Impaired clinical utility of sequential patient GEM blood gas measurements associated with calibration schedule.

Background: Within- and/or between-instrument variation may falsely indicate patient trends or obscure real trends. We employ a methodology that transforms sequential intra-patient results into estimates of biologic and analytic variation. We previously derived realistic biologic variation (s) of blood gas (BG) and hematology analytes.

Novel Approach to Establishing an Aldosterone: Renin Ratio Cutoff for Primary Aldosteronism.

Direct renin concentration is replacing plasma renin activity in many laboratories for the investigation of primary aldosteronism, which may have a significant impact on the resulting aldosterone:renin ratios. We sought to develop a population-based approach to establishing an aldosterone:renin ratio cutoff when transitioning between assays. A population-based study was performed in Calgary, Alberta, Canada of 4301 individuals who received testing from January 2012 to November 2015.