Missed acute myocardial infarction in the emergency department-standardizing measurement of misdiagnosis-related harms using the SPADE method.

OBJECTIVES: Diagnostic error is a serious public health problem. Measuring diagnostic performance remains elusive. We sought to measure misdiagnosis-related harms following missed acute myocardial infarctions (AMI) in the emergency department (ED) using the symptom-disease pair analysis of diagnostic error (SPADE) method. METHODS: Retrospective administrative data analysis (2009-2017) from a single, integrated health system using International Classification of Diseases (ICD) coded discharge diagnoses. We looked back 30 days from AMI hospitalizations for antecedent ED treat-and-release visits to identify symptoms linked to probable missed AMI (observed > expected). We then looked forward from these ED discharge diagnoses to identify symptom-disease pair misdiagnosis-related harms (AMI hospitalizations within 30-days, representing diagnostic adverse events). RESULTS: A total of 44,473 AMI hospitalizations were associated with 2,874 treat-and-release ED visits in the prior 30 days. The top plausibly-related ED discharge diagnoses were "chest pain" and "dyspnea" with excess treat-and-release visit rates of 9.8% (95% CI 8.5-11.2%) and 3.4% (95% CI 2.7-4.2%), respectively. These represented 574 probable missed AMIs resulting in hospitalization (adverse event rate per AMI 1.3%, 95% CI 1.2-1.4%). Looking forward, 325,088 chest pain or dyspnea ED discharges were followed by 508 AMI hospitalizations (adverse event rate per symptom discharge 0.2%, 95% CI 0.1-0.2%). CONCLUSIONS: The SPADE method precisely quantifies misdiagnosis-related harms from missed AMIs using administrative data. This approach could facilitate future assessment of diagnostic performance across health systems. These results correspond to ∼10,000 potentially-preventable harms annually in the US. However, relatively low error and adverse event rates may pose challenges to reducing harms for this ED symptom-disease pair.

Identification and expression of a new delta-12 fatty acid desaturase (FAD2-4) gene in upland cotton and its functional expression in yeast and Arabidopsis thaliana plants.

A cotton (Gossypium hirsutum L.) genomic clone encompassing a 17.9-kb DNA fragment was found to contain a delta-12 fatty acid desaturase gene (designated FAD2-4). The FAD2-4 open reading frame has 1,155bp and is uninterrupted, encoding a conceptual FAD2-4 polypeptide of 384 amino acids that has 98% identity with the cotton FAD2-3 polypeptide. The FAD2-4 gene has a single intron of 2,780 bp in its 5'-untranslated region (5'-UTR). The 3'-flanking regions and 5'-UTR introns in the FAD2-4 and FAD2-3 genes are quite different, indicating that the genes might be paralogs in the cotton genome. Reverse transcriptase (RT)-PCR analysis indicated that the FAD2-4 and FAD2-3 genes were expressed in all tissues examined, including seeds, seedling tissues, young and mature leaves, roots, stems, developing flower buds, and ovule fibers. These constitutive patterns of expression were notably different from that of the FAD2-1 gene, which was restricted to seeds and developing flower buds, or to the expression of a newly-identified FAD2-2 gene isoform, which was barely detectable in roots, hypocotyls, stems, and fibers, but was expressed in all other tissues. The FAD2-4 coding region was expressed in yeast and shown to encode a functional delta-12 desaturase, converting oleic acid (C18:1) to linoleic acid (C18:2) in recombinant yeast cells. In addition, both the FAD2-4 and the FAD2-3 genes were transferred into the Arabidopsis thaliana fad2-1 mutant background where they effectively restored wild type fatty acid composition and growth characteristics. Finally, the cotton FAD2-4 green fluorescent protein (GFP) fusion polypeptide appeared to be localized in the endomembrane system of transgenic Arabidopsis plants in the complemented fad2-1 mutant background, supporting a functional ER location for the cotton FAD2-4 polypeptide in this heterologous plant system. Thus, a new functional member of the FAD2 gene family in cotton has been characterized, indicating a complex regulation of membrane lipid desaturation in this important fiber/oilseed crop.