An Introduction to the Complete Blood Count for Clinical Chemists: Red Blood Cells.

Background: The most frequently ordered laboratory test worldwide is the complete blood count (CBC).

Content: In this primer, the red blood cell test components of the CBC are introduced, followed by a discussion of the laboratory evaluation of anemia and polycythemia.

Summary: As clinical chemists are increasingly tasked to direct laboratories outside of the traditional clinical chemistry sections such as hematology, expertise must be developed.

An Introduction to the Complete Blood Count for Clinical Chemists: Platelets.

Background: The most ordered laboratory test worldwide is the complete blood count (CBC).

Content: In this primer, an introduction to platelet testing in the context of the CBC is provided with a discussion of the laboratory evaluation of platelet abnormalities including thrombocytopenia and thrombocytosis.

Summary: As clinical chemists continue to be tasked to direct laboratories outside of the traditional clinical chemistry sections such as hematology, expertise must be developed.

Advances in sepsis biomarkers.

Sepsis, a dysregulated host immune response to an infectious agent, significantly increases morbidity and mortality for hospitalized patients worldwide. This chapter reviews (1) the basic principles of infectious diseases, pathophysiology and current definition of sepsis, (2) established sepsis biomarkers such lactate, procalcitonin and C-reactive protein, (3) novel, newly regulatory-cleared/approved biomarkers, such as assays that evaluate white blood cell properties and immune response molecules, and (4) emerging biomarkers and biomarker panels to highlight future directions and opportunities in the diagnosis and management of sepsis.

The stability of blood gases and CO-oximetry under slushed ice and room temperature conditions.

Objectives: Human blood gas stability data is limited to small sample sizes and questionable statistical techniques. We sought to determine the stability of blood gases under room temperature and slushed iced conditions in patients using survival analyses.

Methods: Whole blood samples from ∼200 patients were stored in plastic syringes and kept at room temperature (22-24 °C) or in slushed ice (0.

Reducing Specimen Rejection Rates Using Concentration-Dependent Hemolysis Rejection Thresholds.

Background: Using middleware solutions, it is possible to implement concentration-dependent analyte-specific hemolysis rejection limits. This makes day-to-day reporting of clinical specimens more efficient and potentially lowers sample rejection rates compared to a "one-size-fits-all" approach (i.e.

Clinically actionable genotypes for anticancer prescribing among >1500 patients with pharmacogenomic testing.

Background: In recent years, there has been increasing evidence supporting the role of germline pharmacogenomic factors predicting toxicity for anticancer therapies. Although somatic genomic data are used frequently in oncology care planning, germline pharmacogenomic testing is not. This study hypothesizes that comprehensive germline pharmacogenomic profiling could have high relevance for cancer care.

Applicability of Pharmacogenomically Guided Medication Treatment during Hospitalization of At-Risk Minority Patients.

Known disparities exist in the availability of pharmacogenomic information for minority populations, amplifying uncertainty around clinical utility for these groups. We conducted a multi-site inpatient pharmacogenomic implementation program among self-identified African-Americans (AA; = 135) with numerous rehospitalizations ( = 341) from 2017 to 2020 (NIH-funded ACCOuNT project/clinicaltrials.gov#NCT03225820).

Large inter-assay difference of serum creatinine in pediatric population: a threat to accurate staging of chronic kidney disease.

Background: Serum creatinine concentration is a primary component of Bedside Schwartz equation for estimated glomerular filtration rate (eGFR) in children. To standardize creatinine measurement, most manufacturers have adopted calibration procedures traceable to isotope dilution mass spectrometry (IDMS) using National Institute of Standards and Technology reference material. However, reference material representing much lower creatinine concentrations seen in children is not available and it is unclear how well commercial assays perform at pediatric levels.

Stability of Whole Blood Electrolyte Specimens at Room Temperature vs. Slushed Ice Conditions.

Background: Data on the stability of whole blood electrolytes is limited to small sample sizes. We sought to determine the stability of whole blood electrolytes under room temperature and slushed iced conditions in human patients at a major hospital center.

Methods: Whole blood samples were obtained from 203 patients hospitalized for various pathophysiological conditions.

Impact of CYP2D6 Pharmacogenomic Status on Pain Control Among Opioid-Treated Oncology Patients.

Background: Several opioids have pharmacogenomic associations impacting analgesic efficacy. However, germline pharmacogenomic testing is not routinely incorporated into supportive oncology. We hypothesized that CYP2D6 profiling would correlate with opioid prescribing and hospitalizations.

Development of an LC-MS/MS Method for Measurement of Irinotecan and Its Major Metabolites in Plasma: Technical Considerations.

Objective: Irinotecan (CPT-11) is an important drug used in the treatment of several solid tumor types. To minimize its toxicity, therapeutic drug monitoring of CPT-11 and its major metabolites (SN-38, SN-38-glucuronide [SN-38G], and APC) has been proposed. We aimed to develop a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the quantification of CPT-11 and its major metabolites in plasma.

Validation of a Large Custom-Designed Pharmacogenomics Panel on an Array Genotyping Platform.

Background: Pharmacogenomics has the potential to improve patient outcomes through predicting drug response. We designed and evaluated the analytical performance of a custom OpenArray® pharmacogenomics panel targeting 478 single-nucleotide variants (SNVs).

Methods: Forty Coriell Institute cell line (CCL) DNA samples and DNA isolated from 28 whole-blood samples were used for accuracy evaluation.

A retrospective analysis of high sensitivity cardiac troponin-T ranges in non-myocardial infarction emergency department visits.

Introduction: Current evidence suggests that high sensitivity cardiac troponin-T (hs-cTnT) values differ based on sex, race, age, and kidney function. However, most studies examining the relationship of hs-cTnT and these individual factors are in healthy participants, leading to difficulty in interpreting hs-cTnT values in the Emergency Department (ED) setting. We seek to examine the relationship between hs-cTnT values and sex, race, age, and kidney function in a contemporary, urban academic setting.

Role of von Willebrand Factor in COVID-19 Associated Coagulopathy.

Background: COVID-19, the disease caused by SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) can present with symptoms ranging from none to severe. Thrombotic events occur in a significant number of patients with COVID-19, especially in critically ill patients. This apparent novel form of coagulopathy is termed COVID-19-associated coagulopathy (CAC), and endothelial derived von Willebrand factor (vWF) may play an important role in its pathogenesis.

Cardiac Troponin Composition Characterization after Non ST-Elevation Myocardial Infarction: Relation with Culprit Artery, Ischemic Time Window, and Severity of Injury.

Background: Troponin composition characterization has been implicated as a next step to differentiate among non-ST elevation myocardial infarction (NSTEMI) patients and improve distinction from other conditions with troponin release. We therefore studied coronary and peripheral troponin compositions in relation to clinical variables of NSTEMI patients.

Methods: Samples were obtained from the great cardiac vein (GCV), coronary sinus (CS), and peripheral circulation of 45 patients with NSTEMI.

Implementation of pharmacogenomic testing in oncology care (PhOCus): study protocol of a pragmatic, randomized clinical trial.

Background: Many cancer patients who receive chemotherapy experience adverse drug effects. Pharmacogenomics (PGx) has promise to personalize chemotherapy drug dosing to maximize efficacy and safety. Fluoropyrimidines and irinotecan have well-known germline PGx associations.

Evaluation of Biomarkers in Sepsis: High Dimethylarginine (ADMA and SDMA) Concentrations Are Associated with Mortality.

Background: As modulators of nitric oxide generation, asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) may play important roles in sepsis. Current data on dimethylarginines are conflicting, and direct comparison data with other biomarkers are limited.

Methods: Fifty-five patients were included in the final analysis and were divided into 4 groups: infection without sepsis, sepsis, severe sepsis, and septic shock.

A comparison of venous blood gas analysis with paired specimens collected in syringes and evacuated blood collection tubes.

Background: Venous blood samples collected in evacuated blood collection tubes are generally not considered suitable for measurement of oxygenation status. However, whether pH, pCO and HCO results from venous blood samples collected in evacuated tubes are reliable remains unclear.

Methods: Paired samples were collected from 38 healthy volunteers using two collection methods: (1) collection of blood directly into a blood gas syringe and (2) collection of blood into an evacuated tube with subsequent anaerobic transfer into a blood gas syringe.