Alberta Hospital Edmonton

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Abstract Background Laboratory tests are increasingly important for diagnosing multiple sclerosis (MS). Cerebrospinal fluid (CSF) laboratory testing, including detection of CSF oligoclonal bands (OCB), aids in the diagnosis of MS but significant variability in reporting practices across Canadian clinical laboratories has been shown. To address this issue, the Harmonized CSF Analysis for MS Investigation (hCAMI) subcommittee of the Canadian Society of Clinical Chemists (CSCC) Reference Interval Harmonization (hRI) Working Group was formed. Methods The hCAMI subcommittee, comprised of clinical chemists and neurologists, identified key areas of CSF laboratory testing for MS investigation that require harmonization and formulated specific questions for targeted recommendations. The subcommittee comprehensively reviewed the literature, surveyed clinical chemists regarding current practices and neurologists on reporting preferences, and conducted studies to answer these questions. Recommendation statements were drafted and will undergo the Delphi process for refinement to ultimately generate evidence-based consensus statements. Results Six key areas for harmonization were identified: (1) quality control practices, (2) timing considerations for matched CSF and serum sample collection, (3) reporting protocols for band counts, (4) interpretation and follow-up for other patterns (i.e., monoclonal gammopathy, inflammatory response), (5) handling of matched band intensity variations, and (6) defining panel components and reference intervals/decision limits. Literature and data were reviewed for each key area. Draft recommendations were developed and will undergo iterative refinement via the Delphi process. Conclusion Harmonized laboratory reporting recommendations will lead to consistency and alignment of CSF laboratory testing for diagnosis of MS across Canada. This subcommittee’s efforts will promote evidence-based standardized reporting practices to improve diagnostic accuracy and patient care.

Abstract Background Neonatal total bilirubin (NBIL) results are used to guide the medical need for phototherapy or exchange transfusion in babies. When sample analysis occurs across multiple vendors and instrument platforms, clinical result interpretation challenges can occur. This study evaluated the performance of NBIL methods across multiple general chemistry analyzers - Roche Cobas, Siemens Atellica, and Ortho Vitros - using pooled neonatal plasma samples. NBIL was measured as total bilirubin on Roche Cobas and Siemens Atellica, whereas on Ortho Vitros, it was measured as the sum of conjugated and unconjugated bilirubin fractions (Bc and Bu) using dry slide chemistry. Methods Residual neonatal plasma samples were collected at selected hospital laboratories in Alberta, Canada, and pooled. This was a process requiring meticulous effort due to the small volume typically available from each neonate. Pooled samples were divided into five sets and analyzed in duplicates at separate clinical laboratories using the NBIL method on the respective platform (two laboratories using Roche Cobas (8000 vs Pro), two laboratories using Ortho Vitros XT3400 BuBc slides (two slide generations) and one laboratory using Siemens Atellica. Results from each platform were compared to assess method performance and bias. Graphical and statistical analysis were completed, including Passing Bablok regression analysis. Total allowable difference used for the data analysis was ±20% or 6.84 umol/L. Results Method comparisons reveal up to 29% bias for neonatal bilirubin measurements between Roche Cobas and Siemens Atellica platforms, with an average bias of +27%. Ortho Vitros XT3400 showed an average bias of +11% compared to Roche Cobas. Among the three platforms studied, Siemens Atellica demonstrated the highest bias, while Roche Cobas consistently ran lower compared to the other platforms, with Vitros XT3400 positioned in between. Passing Bablok regression revealed the following relationships:Ortho Vitros (X) vs. Atellica (Y): y=1.12x-0.34Roche Cobas (X) vs. Atellica (Y): y=1.27x-0.26Ortho Vitros (X) vs. Roche Cobas (Y): y=0.86x+2.98 The average bias between two generation of slides installed on two Vitros analyzers was 0.3%, while the average difference between Cobas Pro and Cobas 8000 was 2.9%. Conclusions: Among the three vendor platform families studied, Siemens Atellica demonstrated the highest bias, while Roche Cobas was consistently lower compared to the other two platforms. These discrepancies underscore the critical need for mitigation strategies and assay performance assessment by the vendor to significantly reduce inter-platform bias, to better support patient care, minimize unnecessary or excessive patient management, and ensure consistent and reliable neonatal care. Given the significant variability observed between different vendor platforms for NBIL it is crucial for manufacturers to minimize within-platform inconsistencies. While inter-platform differences can pose challenges for clinical interpretation, reducing variability within a single manufacturer*s systems can help improve result reliability and standardization.

Abstract Background Hemolysis, icterus, and lipemia (HIL) are common sources of interference, potentially introducing bias and affecting the accuracy of patient results. Studies performed by manufacturers to establish HIL thresholds for interference vary across platforms and data is often limited. This study evaluates the relationship between interferent concentrations and HIL indices, and the impact of HIL interference on chemistry analytes measured on Ortho Vitros and Roche Cobas. Methods CLSI EP07-ED:2018 guidelines on evaluation of HIL interference were followed. Pooled patient plasma (N=3 per analyte) was spiked with saline (control) or increasing concentrations of hemolysate, bilirubin, or intralipid and analyzed in triplicate for 18 chemistry analytes on Ortho Vitros XT3400 (Vitros) and Roche Cobas Pro c503 (Roche) analyzers. A subset of analytes were evaluated across a broad concentration range while others were selected within the reference interval. Differences between spiked and control samples were calculated to determine interference bias. Results were compared to locally established allowable total errors (ATE) and compared to manufacturer-provided interference thresholds. Results Instrument and analyte specific differences for HIL were identified. ALP was more resistant to hemolysis on Roche than on Vitros. On Vitros, ALP bias was concentration-dependent, with increasing sensitivity to interference from hemoglobin at low ALP concentration. Total bilirubin and albumin were sensitive to hemolysis interference on Vitros, but resistant to hemolysis on Roche. Conversely, sodium was more resistant to hemolysis on Vitros but showed interference on Roche. For lipemia, Vitros showed greater resistance to interference for ALT, AST, chloride, and sodium compared to Roche. For icterus, Vitros demonstrated resistance to interference for all analytes assayed, where Roche showed concentration-dependent interference for creatinine, with increased sensitivity at lower concentrations of creatinine. Conclusion Our study showed differences in HIL interference between Roche and Vitros, with Vitros showing greater resistance, particularly to lipemia and icterus. Interference varied in a concentration-dependent manner, supporting the use of concentration-specific thresholds, especially for ALT, ALP, and AST. For many analytes on both analyzers, interference thresholds deviated from manufacturer recommendations, with higher-than-expected hemolysis thresholds and lower lipemia thresholds. These findings highlight the need for laboratories to verify HIL interference and establish optimal, analyzer-specific thresholds.

Many survivors of traumatic injuries are affected by mental disorders, which has recently led to the publication of clinical practice guidelines (CPGs). However, there is no comprehensive synthesis of guideline recommendations to inform clinicians on those that should be prioritized for implementation and thus promote adherence to them. To identify guideline recommendations for the prevention and management of mental disorders in patients with traumatic injuries, appraise their quality, and synthesize the quality of evidence and the strength of included recommendations. MEDLINE, Embase, CINAHL, PsycINFO, Cochrane Central, Web of Science, and 61 websites of professional associations and guideline repositories were searched between January 2008 and September 2024. We included CPGs pertinent to the acute and early recovery phases (<3 months) of adult patients (≥18 years) with traumatic injuries with at least 1 recommendation on mental health. Pairs of reviewers independently extracted data and assessed guideline quality using the Appraisal of Guidelines Research and Evaluation (AGREE) II tool. The quality of evidence on recommendations was synthesized using a matrix based on the categories of the Grading of Recommendations, Assessment, Development and Evaluation (GRADE). Mental health recommendations had to target prevention, screening, evaluation, intervention, referral for follow-up or specialized services, and a patient- and family-centered care approach. Forty-three CPGs were included, 25 of which (58%) were high quality. Rigor of development, applicability, lack of involvement from all interested parties, and editorial independence were the most common methodological weaknesses. High-quality CPGs included 200 recommendations; of these, 50 (25%) were supported by moderate- to high-quality evidence and 30 (60%) targeted patients with traumatic brain injury. They covered mainly nonpharmacological and pharmacological interventions to treat acute stress disorder, substance use disorders, posttraumatic stress disorder, depression, or aggression. Fewer recommendations related to prevention, screening, evaluation, and referral were identified as having high empirical support. Fifty recommendations were identified that may be considered for implementation in clinical settings in patients with traumatic brain injury and other trauma populations. Our review underlines important areas for future research, including training for clinicians, a patient- and family-centered care approach, and health care equity.