Patient and specimen identification in a tertiary care pediatric hospital: Barcodes do not scan themselves.

BACKGROUND: Despite the safety improvements linked to the use of barcodes for patient and specimen identification, patient misidentification remains a leading cause of transfusion-associated reactions including fatalities. A wealth of evidence supports the use of barcodes in general, but there is less published evidence of real-world barcode compliance. This project investigates barcode scanning compliance for patient and specimen identification at a tertiary care pediatric/maternity hospital. STUDY DESIGN AND METHODS: Transfusion laboratory specimen collection noncompliance events between January 1, 2019, and December 31, 2019 were retrieved from the hospital laboratory information system. Data were analyzed including stratification of collections by collector role and collection event. A survey of blood collectors was conducted. RESULTS: Collection compliance for 6285 blood typing specimens was evaluated. Full barcode scanning identification of both patient and specimen was utilized in only 33.6% of total collections. The remaining two thirds of collections were overridden by the blood collector: no barcode scanning occurred in 31.3%, while the specimen accession label was scanned but not the patient armband in 32.3% of total collections. There were significant differences between phlebotomists and nurses, with more phlebotomists performing the full scanning and specimen scanning only, while more nurses obtained specimens without patient or specimen scanning (p < .001). Blood collectors identified hardware challenges and training gaps as key contributors to barcode noncompliance. DISCUSSION: Our study highlights an instance of poor barcode scanning compliance for patient and specimen identification. We formulated improvement strategies and launched a quality improvement project to address factors influencing noncompliance.

NUP98-HOXA9-transgenic zebrafish develop a myeloproliferative neoplasm and provide new insight into mechanisms of myeloid leukaemogenesis.

NUP98-HOXA9 [t(7;11) (p15;p15)] is associated with inferior prognosis in de novo and treatment-related acute myeloid leukaemia (AML) and contributes to blast crisis in chronic myeloid leukaemia (CML). We have engineered an inducible transgenic zebrafish harbouring human NUP98-HOXA9 under the zebrafish spi1(pu.1) promoter. NUP98-HOXA9 perturbed zebrafish embryonic haematopoiesis, with upregulated spi1 expression at the expense of gata1a. Markers associated with more differentiated myeloid cells, lcp1, lyz, and mpx were also elevated, but to a lesser extent than spi1, suggesting differentiation of early myeloid progenitors may be impaired by NUP98-HOXA9. Following irradiation, NUP98-HOXA9-expressing embryos showed increased numbers of cells in G2-M transition compared to controls and absence of a normal apoptotic response, which may result from an upregulation of bcl2. These data suggest NUP98-HOXA9-induced oncogenesis may result from a combination of defects in haematopoiesis and an aberrant response to DNA damage. Importantly, 23% of adult NUP98-HOXA9-transgenic fish developed a myeloproliferative neoplasm (MPN) at 19-23 months of age. In summary, we have identified an embryonic haematopoietic phenotype in a transgenic zebrafish line that subsequently develops MPN. This tool provides a unique opportunity for high-throughput in vivo chemical modifier screens to identify novel therapeutic agents in high risk AML.

Fluorescence-activated cell sorting (FACS) of whole mount in situ hybridization (WISH) labelled haematopoietic cell populations in the zebrafish.

The zebrafish is a robust animal model for studying vertebrate haematopoiesis and immune cell interactions. However, fluorescence activated cell sorting (FACS) has been limited due to a paucity of available functional zebrafish antibodies. We have developed a technique combining FACS with whole mount in situ hybridization (WISH) that enables the sorting and examining of fixed zebrafish blood cell populations at different stages of embryonic development, providing the opportunity to correlate RNA expression data with cellular morphology.

Zebrafish mast cells possess an FcɛRI-like receptor and participate in innate and adaptive immune responses.

We previously identified a zebrafish mast cell (MC) lineage and now aim to determine if these cells function analogously in innate and adaptive immunity like their mammalian counterparts. Intraperitoneal (IP) injection of compound 48/80 or live Aeromonas salmonicida resulted in significant MC degranulation evident histologically and by increased plasma tryptase compared with saline-injected controls (p=0.0006, 0.005, respectively). Pre-treatment with ketotifen abrogated these responses (p=0.0004, 0.005, respectively). Cross-reactivity was observed in zebrafish to anti-human high-affinity IgE receptor gamma (FcɛRIγ) and IgE heavy chain-directed antibodies. Whole mount in situ hybridization on 7-day embryos demonstrated co-localization of cpa5, a MC-specific marker, with myd88, a toll-like receptor adaptor, and zebrafish FcɛRI subunit homologs. Zebrafish injected IP with matched dinitrophenyl-sensitized mouse (anti-DNP) IgE and DNP-BSA or trinitrophenyl-sensitized mouse (anti-TNP) IgE and TNP-BSA demonstrated increased plasma tryptase compared with mismatched controls (p=0.03, 0.010, respectively). These results confirm functional conservation and validate the zebrafish model as an in vivo screening tool for novel MC modulating agents.