A guide to conducting systematic reviews of clinical laboratory tests.

Clinical laboratory professionals have an instrumental role in supporting clinical decision making with the optimal use of laboratory testing for screening, risk stratification, diagnostic, prognostic, treatment selection and monitoring of different states of health and disease. Delivering evidence-based laboratory medicine relies on review of available data and literature. The information derived, supports many national policies to improve patient care through clinical practice guidelines or best practice recommendations.

Lipid distributions in the Global Diagnostics Network across five continents.

Aims: Lipids are central in the development of cardiovascular disease, and the present study aimed to characterize variation in lipid profiles across different countries to improve understanding of cardiovascular risk and opportunities for risk-reducing interventions.

Methods And Results: This first collaborative report of the Global Diagnostics Network (GDN) evaluated lipid distributions from nine laboratory organizations providing clinical laboratory testing in 17 countries on five continents. This cross-sectional study assessed aggregated lipid results from patients aged 20-89 years, tested at GDN laboratories, from 2018 through 2020.

Current use of bone turnover markers in the management of osteoporosis.

The adult bone is continuously being remodelled to repair microdamage, preserve bone strength and mechanical competence as well as maintain calcium homeostasis. Bone turnover markers are products of osteoblasts (bone formation markers) and osteoclasts (bone resorption markers) providing a dynamic assessment of remodelling (turnover). Resorption-specific bone turnover markers are typically degradation products of bone collagen molecules (N- [NTX] and C-telopeptide cross-linked type 1 collagen [CTX]), which are released into the circulation and excreted in urine; or enzymatic activities reflecting osteoclastic resorption, tartrate-resistant acid phosphatase [TRACP].

Lot verification practices in Ontario clinical chemistry laboratories - Results of a patterns-of-practice survey.

Objectives: Verifying new reagent or calibrator lots is crucial for maintaining consistent test performance. The Institute for Quality Management in Healthcare (IQMH) conducted a patterns-of-practice survey and follow-up case study to collect information on lot verification practices in Ontario.

Methods: The survey had 17 multiple-choice questions and was distributed to 183 licensed laboratories.

Hypertension Canada's 2020 Comprehensive Guidelines for the Prevention, Diagnosis, Risk Assessment, and Treatment of Hypertension in Adults and Children.

Hypertension Canada's 2020 guidelines for the prevention, diagnosis, risk assessment, and treatment of hypertension in adults and children provide comprehensive, evidence-based guidance for health care professionals and patients. Hypertension Canada develops the guidelines using rigourous methodology, carefully mitigating the risk of bias in our process. All draft recommendations undergo critical review by expert methodologists without conflict to ensure quality.

Hypertension Canada's 2018 Guidelines for Diagnosis, Risk Assessment, Prevention, and Treatment of Hypertension in Adults and Children.

Hypertension Canada provides annually updated, evidence-based guidelines for the diagnosis, assessment, prevention, and treatment of hypertension in adults and children. This year, the adult and pediatric guidelines are combined in one document. The new 2018 pregnancy-specific hypertension guidelines are published separately.

Assessment of the Measurement Error in Cyclosporine Levels Drawn Between Peripheral and Central Sources.

Objectives: Cyclosporine is often monitored by drug levels drawn through central venous catheters (CVCs), which may be falsely elevated due to reversible drug adsorption onto the catheter. Therefore, we assessed the correlation between cyclosporine levels drawn peripherally and through CVCs.

Methods: Bone marrow transplantation patients had a weekly collection of both peripheral and CVC draws from dual-lumen catheters simultaneously to assess cyclosporine levels after research ethics approval.

Point-of-care testing (POCT) and evidence-based laboratory medicine (EBLM) - does it leverage any advantage in clinical decision making?

Point-of-care testing (POCT) is the analysis of patient specimens outside the clinical laboratory, near or at the site of patient care, usually performed by clinical staff without laboratory training, although it also encompasses patient self-monitoring. It is able to provide a rapid result near the patient and which can be acted upon immediately. The key driver is the concept that clinical decision making may be delayed when samples are sent to the clinical laboratory.

Rates of inappropriate laboratory test utilization in Ontario.

Background: Medical laboratory tests ordered redundantly represent one of the targets for reducing diagnostic testing without negatively, and possibly positively, affecting patient care. We study a clearly defined category of excessive laboratory utilization for nine analytes where inappropriate diagnostic testing is defined in terms of the time interval between tests; that is, ordering a test too soon following the previous order of the same test.

Methods: Population data from the near universal public Ontario Health Insurance Plan for the years 2006-2010 are employed where the tests are fulfilled by community medical laboratories.

Clinical implications of estrone sulfate measurement in laboratory medicine.

Estrone sulfate (ES) is the most abundant circulating estrogen and it has the potential to be used as a biomarker in certain conditions where estimation of low levels of estrogen or changes in relative levels of estrogens are important. This review will critically consider the role of estimating ES for clinical laboratory practice. As ES is an estrogen, a wider discussion of estrogens is included to contextualize the review.

Familial partial lipodystrophy presenting as metabolic syndrome.

We report the first described case of a heterozygous p.R545H (c.1634 G > A) missense mutation in the LMNA gene with clinical features compatible with Dunnigan-type 2 familial partial lipodystrophy (FPLD2).

Grading Evidence for Laboratory Test Studies Beyond Diagnostic Accuracy: Application to Prognostic Testing.

Background: Evidence-based guideline development requires transparent methodology for gathering, synthesizing and grading the quality and strength of evidence behind recommendations. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) project has addressed diagnostic test use in many of their publications. Most of the work has been directed at diagnostic tests and no consensus has been reached for prognostic biomarkers.

Frameshift mutation in the APOA5 gene causing hypertriglyceridemia in a Pakistani family: Management and considerations for cardiovascular risk.

We report a novel homozygous apolipoprotein A5 (APOA5) frameshift mutation (c.G425del-C, p.Arg143AlafsTer57) identified in a 12-year-old boy of Pakistani origin with severe hypertriglyceridemia (up to 35 mmol/L) and type V hyperlipoproteinemia.

Diagnosis and Treatment of Primary Adrenal Insufficiency: An Endocrine Society Clinical Practice Guideline.

Objective: This clinical practice guideline addresses the diagnosis and treatment of primary adrenal insufficiency.

Participants: The Task Force included a chair, selected by The Clinical Guidelines Subcommittee of the Endocrine Society, eight additional clinicians experienced with the disease, a methodologist, and a medical writer. The co-sponsoring associations (European Society of Endocrinology and the American Association for Clinical Chemistry) had participating members.

Evaluation of natriuretic peptide recommendations in heart failure clinical practice guidelines.

Background: The B-type naturietic peptides (NPs) are associated with heart failure (HF). This investigation was designed to evaluate heart failure clinical practice guideline (CPG) recommendations for the use of NPs.

Methods: A search for English language CPGs for HF published since 2011 was conducted.

Successful reintroduction of statin therapy after statin-associated rhabdomyolysis.

The case report demonstrates the successful use of an alternative statin after a statin-related episode of rhabdomyolysis. Statin-associated rhabdomyolysis is a serious adverse event with a very low incidence and is considered the most severe of the muscle-related side effects of the statins. Rechallenge with statins is not a recommended practice after rhabdomyolysis.