Impact of COVID-19 on Drug Positivity Rates in the Emergency Departments in Boston and Surrounding Areas.

Background: The COVID-19 pandemic reportedly had a significant impact on drug and alcohol use. In this article, we determine positivity rates for urine drugs of abuse and blood alcohol in 5 emergency departments (ED) in the greater Boston metropolitan area over a 4-year period (pre-, during, and post-COVID-19 pandemic).

Methods: Positivity rates for the urine drug screening (UDS) panel and blood alcohol concentration (>80 mg/dL; over the legal limit in MA) were calculated in patients presenting to one of the 5 ED (2 academic hospitals in Boston, MA and 3 community hospitals outside Boston, MA) during each of the 4 different time periods: pre-COVID (January 1, 2019 to December 31, 2019), stay-at-home (March 24, 2020 to May 18, 2020), during COVID (May 19, 2020 to March 28, 2021), and post-COVID (May 12, 2023 to August 31, 2023).

Despite the improved clinical sensitivity of the Roche benzodiazepines II assay it cannot replace mass spectrometry in all patient populations.

Introduction: Benzodiazepines are frequently prescribed and misused therefore urine drug screening (UDS) is performed in many patient populations. Most current benzodiazepine immunoassays have poor sensitivity, particularly for detecting the metabolites of newer benzodiazepines such as lorazepam in urine.

Objectives: We aimed to verify the clinical performance of the new qualitative Roche Benzodiazepines II (BNZ2) immunoassay, as well as compare its performance to the Roche Benzodiazepines Plus (BENZ) assay in two patient populations: UDS in the emergency department (ED) and compliance monitoring.

Performance of a Norfentanyl Immunoassay in Specimens with Low Concentrations of Fentanyl and/or Norfentanyl.

Background: Many fentanyl immunoassays are limited in their ability to detect norfentanyl. Urine specimens collected from individuals who have been exposed to fentanyl frequently have detectable concentrations of norfentanyl (≥2 ng/mL) but low concentrations of fentanyl (<2 ng/mL) by LC-MS/MS. The Lin-Zhi Fentanyl II Immunoassay (Lin-Zhi) claims 100% cross-reactivity with norfentanyl and therefore may detect exposure missed by other assays.

Advances in fentanyl testing.

Fentanyl is a synthetic opioid that was approved by the FDA in the late 1960s. In the decades since, non-prescription use of fentanyl, its analogs, and structurally unrelated novel synthetic opioids (NSO) has become a worsening public health crisis. There is a clear need for accessible testing for these substances in biological specimens and in apprehended drugs.

Fentanyl in the labor epidural impacts the results of intrapartum and postpartum maternal and neonatal toxicology tests.

Background: A positive urine fentanyl toxicology test may have considerable consequences for peripartum individuals, yet the extent to which fentanyl administration in a labor epidural may lead to such a positive test is poorly characterized.

Objective: This study aimed to quantify the extent to which neuraxial fentanyl in labor neuraxial analgesia can lead to a positive peripartum maternal or neonatal urine toxicology test.

Study Design: We performed a prospective cohort study of pregnant participants planning a vaginal delivery with neuraxial analgesia.

Bupivacaine Metabolite Can Interfere with Norfentanyl Measurement by LC-MS/MS.

Background: Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) is the gold standard for the measurement of fentanyl and norfentanyl (NF) in urine and is favored over immunoassays due to its superior specificity. NF is the principal metabolite of fentanyl found in the urine and is typically present in higher abundance than fentanyl. Thus, the sensitivity and specificity of LC-MS/MS relies largely on the ability to identify and quantitate NF.

Impact of marijuana legalization on cannabis-related visits to the emergency department.

Background: Cannabis is widely used in the United States despite federal laws. In US states that have progressed toward legalization, there have been various reported impacts on cannabis-related emergency department (ED) visits. However, studies on the impact of legalization in Massachusetts (MA) EDs are lacking.

Comparison of Oral Fluid and Urine for Detection of Fentanyl Use Using Liquid Chromatography with Tandem Mass Spectrometry.

Background: We compared oral fluid (OF) and urine (UR) for detection of fentanyl (FEN) use in addiction medicine-psychiatry (AMP) clinics.

Methods: We measured FEN and norfentanyl (NRFEN) in UR with a limit of detection (LOD) of 2.0 µg/L and FEN in OF with an LOD of 0.

Validation and Implementation of an Ordering Alert to Improve the Efficiency of Monoclonal Gammopathy Evaluation.

Objectives: To evaluate the use of a provider ordering alert to improve laboratory efficiency and reduce costs.

Methods: We conducted a retrospective study to assess the use of an institutional reflex panel for monoclonal gammopathy evaluation. We then created a clinical decision support (CDS) alert to educate and encourage providers to change their less-efficient orders to the reflex panel.

Vortioxetine use may cause false positive immunoassay results for urine methadone.

Background: Urine immunoassays are frequently employed for methadone screening because they are relatively inexpensive and widely available. However, immunoassays are notoriously prone to false positives. We report that the use of vortioxetine (Trintellix® in the USA and Canada, Brintellix® worldwide) could cause false positives in the Roche KIMS Methadone II Urine immunoassay (MDN2).

STK40 Is a Pseudokinase that Binds the E3 Ubiquitin Ligase COP1.

Serine/threonine kinase 40 (STK40) was originally identified as a distant homolog of Tribbles-family proteins. Despite accumulating data attesting to the importance of STK40 in a variety of different physiologic processes, little is known about its biological activity or mechanism of action. Here, we show that STK40 interacts with Constitutive Photomorphogenic Protein 1 (COP1), relying primarily on a C-terminal sequence analogous to the motif found in Tribbles proteins.

Structural Basis for Substrate Selectivity of the E3 Ligase COP1.

COP1 proteins are E3 ubiquitin ligases that regulate phototropism in plants and target transcription factors for degradation in mammals. The substrate-binding region of COP1 resides within a WD40-repeat domain that also binds to Trib proteins, which are adaptors for C/EBPα degradation. Here we report structures of the human COP1 WD40 domain in isolation, and complexes of the human and Arabidopsis thaliana COP1 WD40 domains with the binding motif of Trib1.

Comparative response assessment by serum immunoglobulin M M-protein and total serum immunoglobulin M after treatment of patients with Waldenström macroglobulinemia.

Serum immunoglobulin (Ig) M monoclonal protein determined by electrophoresis (sIgM-MP) and total serum IgM (sIgM) by nephelometry are widely used for response assessment in Waldenström macroglobulinemia (WM), although have not been compared for predicting changes in underlying disease burden. We, therefore, compared these serum markers with changes in bone marrow (BM) and extramedullary disease for 73 patients who were rituximab naive and treated with a rituximab-containing regimen. By linear regression analysis, reductions in sIgM-MP and sIgM showed moderate correlation with BM disease involvement (r = 0.

Challenges with serum protein electrophoresis in assessing progression and clinical response in patients with Waldenström macroglobulinemia.

Accurate determination of the immunoglobulin (Ig) M paraprotein concentration is crucial to evaluating response in patients with Waldenström macroglobulinemia (WM). In most clinical laboratories, M-spike quantitation is performed by serum protein electrophoresis, which is the same method used to quantitate IgG and IgA paraproteins in patients with multiple myeloma (MM). However, the migration pattern and propensity of IgM paraproteins to form higher-order complexes in serum makes laboratory evaluation of samples from patients with WM especially challenging.

Serial serum free light chain measurements do not detect changes in disease status earlier than electrophoretic M-spike measurements in patients with intact immunoglobulin myeloma.

Background: Serum free light chains (SFLC) are used to manage patients with light chain or hyposecretory myeloma, and may also be useful in patients with intact immunoglobulin myeloma (IIMM), because their shorter half-life may enable earlier indication of relapse/response than electrophoretic M-spikes or heavy chain (IgGA) immunonephelometry.

Methods: One thousand five SFLC, M-spike, and IgGA concentrations were compared at multiple time points during the treatment of 17 myeloma patients, followed over 7.7-63.

Transformation by Tribbles homolog 2 (Trib2) requires both the Trib2 kinase domain and COP1 binding.

Tribbles homolog 2 (Trib2) is a pseudokinase that induces acute myelogenous leukemia (AML) in mice and is highly expressed in a subset of human AML. Trib2 has 3 distinct regions, a proline-rich N-terminus, a serine/threonine kinase homology domain, and a C-terminal constitutive photomorphogenesis 1 (COP1)-binding domain. We performed a structure-function analysis of Trib2 using in vitro and in vivo assays.

Differential ability of Tribbles family members to promote degradation of C/EBPalpha and induce acute myelogenous leukemia.

Trib1, Trib2, and Trib3 are mammalian homologs of Tribbles, an evolutionarily conserved Drosophila protein family that mediates protein degradation. Tribbles proteins function as adapters to recruit E3 ubiquitin ligases and enhance ubiquitylation of the target protein to promote its degradation. Increased Trib1 and Trib2 mRNA expression occurs in human myeloid leukemia and induces acute myeloid leukemia in mice, whereas Trib3 has not been associated with leukemia.

Human DNA polymerase kappa encircles DNA: implications for mismatch extension and lesion bypass.

Human DNA polymerase kappa (Pol kappa) is a proficient extender of mispaired primer termini on undamaged DNAs and is implicated in the extension step of lesion bypass. We present here the structure of Pol kappa catalytic core in ternary complex with DNA and an incoming nucleotide. The structure reveals encirclement of the DNA by a unique "N-clasp" at the N terminus of Pol kappa, which augments the conventional right-handed grip on the DNA by the palm, fingers, and thumb domains and the PAD and provides additional thermodynamic stability.