Reported Awareness and Use of Pyridoxal-5'-Phosphate Supplementation in Alanine Aminotransferase and Aspartate Aminotransferase Assay Reagents: A Survey by the College of American Pathologists Clinical Chemistry Committee.

Context.—: Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) assay reagents are available both with and without supplementation with pyridoxal-5'-phosphate (P5P; the active form of vitamin B6), a catalytic cofactor required for their enzymatic reactions. Nonsupplemented assays may miss ALT or AST elevations in patients with vitamin B6 deficiency.

The US FDA's proposed rule on laboratory-developed tests: Impacts on clinical laboratory testing.

Objectives: To solicit quantifiable feedback from clinical laboratorians on the U.S. Food and Drug Administration (FDA) proposed rule to regulate laboratory-developed tests (LDTs) as medical devices.

Robust Response of the Clinical Laboratory to the COVID-19 Pandemic despite Significant Challenges.

Background: Clinical laboratories immediately provided rapid, reliable, and high-throughout diagnostic testing for COVID-19, which was an essential component in combating the pandemic. As the pandemic evolved, the clinical laboratory was faced with additional challenges. However, there are limited studies on the impact of the pandemic on the clinical laboratory over the past 3 years.

Laboratory-Developed Tests Account for a Small Minority of Tests Ordered in an Academic Hospital System.

Objectives: To determine the frequency of use of laboratory-developed tests (LDTs) in an academic medical center system.

Methods: Retrospective analysis of 2021 test order data from an academic medical center (hospital, outpatient clinics, and cancer center) was done. Measures included assay type, assay methodology, regulatory status, test order volume, inpatient vs outpatient setting, and provider medical specialty.

Evaluation of an adenosine deaminase (ADA) assay in serum, pleural, pericardial, peritoneal, and cerebrospinal fluids on the Roche cobas c501 analyzer.

Objectives: Adenosine deaminase (ADA) can be increased in various body fluids during infectious and inflammatory states. The objective of this study was to evaluate the performance characteristics of the Diazyme ADA assay for serum, pleural, pericardial, peritoneal, and cerebrospinal fluids using the Roche cobas c501 analyzer.

Methods: Accuracy, linearity, recovery, precision, sensitivity, specificity, reference interval, and stability studies were conducted.

Impact of Unconjugated estriol (uE3) assay interference on prenatal screening tests.

Background: Unconjugated estriol (uE3) is an important biomarker in second trimester prenatal screening. Previous studies from our laboratory identified rare interference in the Beckman uE3 assay due to anti-ALP antibodies, which could be mitigated with a scavenger or heat-inactivated ALP (hALP). In the current study, 160 de-identified patient samples previously submitted for the Quad screen with low uE3 multiples of the median (MoM ≤0.

Comparison of two chromogranin A assays and investigation of nonlinear specimens.

Background: As a marker for functional and non-functional neuroendocrine tumors, serum chromogranin A (CgA) concentrations have shown value for detecting and monitoring disease. Here we describe a comparison between an established micro-titer plate assay (Cisbio CgA ELISA) and an analyzer-based assay (B·R·A·H·M·S CgA II KRYPTOR). Reference limits were established along with a performance evaluation of the KRYPTOR assay.

An International Survey of Glucose-6-Phosphate Dehydrogenase Laboratory Reporting Practices.

Context.—: Glucose-6-phosphate dehydrogenase (G6PD) activity is used in the evaluation of hemolysis risk in patients being assessed for G6PD deficiency. A long-acting 8-aminoquinoline drug (tafenoquine) used in malaria treatment is contraindicated in patients with G6PD deficiency (<70% normal G6PD activity).

An International Survey of Glucose-6-Phosphate Dehydrogenase Laboratory Reporting Practices: Implications for Tafenoquine Eligibility Assessment.

Context.—: Glucose-6-phosphate dehydrogenase (G6PD) activity is used in the evaluation of hemolysis risk in patients being assessed for G6PD deficiency. A long-acting 8-aminoquinoline drug (tafenoquine) used in malaria treatment is contraindicated in patients with G6PD deficiency (<70% normal G6PD activity).

Tobacco and Cannabis Use During Pregnancy.

Objectives: Nicotine (NIC) use during pregnancy can influence markers used in biochemical maternal serum screening. This study was designed to determine prevalence of disclosed tobacco smokers in our patient population and to compare disclosed tobacco smoking status with the presence of serum nicotine and a common tetrahydrocannabinol (THC) metabolite.

Methods: A deidentified dataset of disclosed smoking status for quadruple (Quad) screens was obtained.

Excessively low cholesterol and triglyceride levels in an apparently healthy patient.

Lipid panels are a commonly performed test in clinical laboratories. Due to the high prevalence of cardiovascular diseases around the world, it is common to see serum or plasma specimens with high results for one or more components of the lipid panel. Exceedingly low results, however, are rare and may be attributed to certain genetic, infectious, or autoimmune conditions in addition to analytical interference.

Performance evaluation of five lipoprotein(a) immunoassays on the Roche cobas c501 chemistry analyzer.

Objectives: Measurement of lipoprotein(a) [Lp(a)] is used in risk assessment of atherosclerotic cardiovascular disease (ASCVD). The aim of the current study was to evaluate performance characteristic of five different Lp(a) assays using the cobas c501 (Roche Diagnostics) analyzer.

Design And Methods: Lp(a) was measured using five Lp(a) assays (Diazyme, Kamiya, MedTest, Randox, and Roche) configured to mg/dL units.

Call for improvement in medical school training in genetics: results of a national survey.

Purpose: To assess, from the student perspective, medical school training in genetics and genomics.

Methods: In 2019, the Undergraduate Training in Genomics (UTRIG) Working Group developed genetics-related survey and knowledge questions for the RISE-FIRST, an exam administered to postgraduate year 1 (PGY1) pathology residents in the United States during their first months of training. Survey questions focused on perceived knowledge in genetics and the structure and quality of training with responses compared with those in control areas.

Pretreatment of Body Fluid Specimens Using Hyaluronidase and Ultracentrifugation.

Objective: Viscous body fluids present challenges during clinical laboratory testing. The present study was conducted to evaluate the effectiveness of hyaluronidase (HYAL) and ultracentrifugation (UC) pretreatment for a variety of body fluids before clinical chemistry testing.

Methods: The following body fluids were evaluated: biliary/hepatic, cerebrospinal, dialysate, drain, pancreatic, pericardial, peritoneal/ascites, pleural, synovial, and vitreous.