Commercial Reference Laboratory Research Articles

Blood stored in EDTA tubes provides accurate peanut basophil activation test results for 48 hours

BackgroundThe peanut basophil activation test (BAT) has demonstrated excellent diagnostic accuracy with heparinized blood, but its clinical utility is limited by the short stability of samples stored in this anticoagulant. ObjectiveUsing EDTA anticoagulated blood, these investigations determined if Peanut BAT sample stability can be extended to 2 days, the minimum stability requirement for diagnostic tests currently offered through American reference laboratories. MethodsPeanut non-allergic control (NAC), peanut IgE sensitized (PS), and peanut allergic (PA) children aged 6 months through 17 years were recruited from members of Kaiser Permanente Southern California. EDTA anti-coagulated blood samples were collected from participants, shipped to a centralized laboratory, and stored at 4oC for peanut BAT testing 1 and 2 days later. ResultsPeanut BAT results for 23 unblinded participants were used to establish sample rejection and interpretation criteria that were subsequently validated in a prospective double-blind study involving 112 additional children (39-NAC, 36-PS, 37-PA). Of 105 blinded blood samples tested on each study day, 88 (84%) day-1 and 90 (86%) day-2 peanut BAT results were considered interpretable, with diagnostic accuracies of 95.5% and 94.4%, respectively. Moreover, all interpretable PA results were considered positive (100% sensitivity). ConclusionUsing EDTA anti-coagulated blood samples collected remotely, 1 and 2 days before testing, study results highlight the favorable diagnostic performance characteristics of the peanut BAT and provide further evidence that the test could be readily operationalized for clinical use by interested commercial reference laboratories.

Retrospective analysis of canine fecal flotation and coproantigen immunoassay hookworm positive results in Greyhounds and other dog breeds

Recent studies demonstrated that Greyhounds are commonly infected with Ancylostoma caninum and these infections have been shown to be resistant to anthelmintics. This study evaluated samples submitted to a commercial reference laboratory (IDEXX Laboratories) for canine fecal flotation zinc sulfate centrifugation and coproantigen immunoassay between January 1, 2019, and July 30, 2023 for evidence that Greyhounds were more often positive for Ancylostoma spp. (hookworms) compared to other breeds. The purpose of the study was to determine if Greyhounds were more likely to be hookworm-positive compared to other breeds, if Greyhounds on preventives with efficacy against hookworm infections are more likely to test positive than other breeds, if their infections take longer to resolve, to estimate how long this takes and to assess whether the proportion of hookworm positive tests for all breeds is increasing over time.Records of 25,440,055 fecal results were obtained representing 17,671,724 unique dogs. Of these, 49,795 (∼0.3%) were Greyhounds. The overall odds ratio (OR) of 15.3 (p < 0.001) suggests that Greyhounds are at significantly higher risk than other breeds for hookworm positive float findings, and the OR of 14.3 (p < 0.001) suggests significantly higher risk for hookworm antigen positive results. The median time to negative testing event from the Turnbull distribution estimate was in the interval of 1–2 days for other breeds and 71–72 days for Greyhounds. These results provide evidence that anthelmintic resistant A. caninum strains may be having population-level impacts on the frequency and duration of infections in Greyhounds. The findings have broader health implications beyond Greyhounds as MADR A. caninum strains could spread to other breeds and even pet owners.

Repeat patient Testing-Quality control: An example of implementation in a network of commercial laboratories.

The theory and calculations underpinning Repeat Patient Testing-Quality Control (RPT-QC) have been presented in prior publications. This paper gives an example of the process used for implementing RPT-QC in a network of veterinary commercial reference laboratories and the stages associated with the transition to the sole use of RPT-QC. To employ RPT-QC in this commercial laboratory network, eight stages of implementation were identified: (1) education, (2) data collection, (3) calculations, (4) QC recording and documentation, (5) running RPT-QC in parallel with a commercially available quality control material (QCM), (6) development of a Standard Operating Procedure (SOP), (7) development of complementary aspects supporting RPT-QC, and (8) sole use of RPT-QC. Advantages of RPT-QC included cost savings for QCM and External Quality Assessment (EQA) participation and the ability to use commutable specimens with a veterinary matrix at a result level that is of clinical significance for the species. A disadvantage of RPT-QC using a single level of control was the inability to demonstrate stable performance over a range of results. Future avenues for investigation include ongoing refinement of control limits using a pooled standard deviation of the duplicates (SDdup), Sdup over time, investigation of blood samples from species other than the dog, and manipulation of specimens to produce "low abnormal" or "high abnormal" RPT-QC specimens.

Clinical next-generation sequencing assay combining full-length gene amplification and shotgun sequencing for the detection of CMV drug resistance mutations

Cytomegalovirus (CMV) causes severe systemic and tissue-invasive disease in immunocompromised patients, particularly solid organ and hematopoietic stem cell transplant recipients. While antiviral drugs offer promising efficacy, clinical management is complicated by the high frequency of drug resistance-associated mutations. The most commonly encountered mutations occur in the genes encoding for the drug targets: UL54 (DNA polymerase), UL56 (terminase complex), and UL97 (phosphotransferase), conferring resistance to ganciclovir/cidofovir/foscarnet, letermovir, and ganciclovir/maribavir, respectively. Currently, standard practice for detecting drug resistance is sequencing-based genotypic analysis by commercial reference laboratories with strictly prescribed sample requirements and reporting parameters that can often restrict testing in a highly vulnerable population. In order to circumvent these limitations, we developed a dual-step next-generation sequencing (NGS)-based clinical assay that utilizes full-length gene amplification by long-range PCR followed by shotgun sequencing for mutation analysis. This laboratory-developed test (LDT) achieved satisfactory performance with 96.4% accuracy, 100% precision, and an analytical sensitivity of 300IU/mL with 20% allele frequency. Highlighted by two clinical cases, our NGS LDT was able to provide critical results from patient specimens with viral loads <500IU/mL and volumes <0.5 mL - conditions otherwise unacceptable by reference laboratories. Here, we describe the development and implementation of a robust NGS LDT that offers greater testing flexibility and sensitivity to accommodate a more diverse patient population.

3D genomics identifies previously unreported yet clinically actionable gene fusions and complex rearrangements in a cohort of driver-negative colorectal carcinoma tumors.

e15608 Background: Molecular characterization by next-generation sequencing (NGS) has been unable to detect pathogenic driver mutations in a significant number of tumors. For example, 40% of colorectal carcinomas (CRC) are RAS and BRAF wild-type and do not have therapeutic targets after comprehensive molecular characterization using FISH, IHC and NGS. Analysis of 3D genomics data produced by DNA-based chromosome conformation capture (Hi-C) assay has been shown to detect gene fusions and other rearrangements in tumor biopsies. We applied Hi-C in a cohort of CRC tumors previously characterized using FISH, IHC, whole exome sequencing (WES) and whole transcriptome sequencing (WTS) by a large commercial reference laboratory, where no targets had been reported, to evaluate the potential for Hi-C to identify novel therapeutic targets. Methods: FFPE tissue from 14 CRC tumors were subjected to Hi-C using the Arima HiC+ for FFPE kit. Hi-C libraries were sequencing to ~100M raw read-pairs on an Illumina NovaSeq, and fusions were called using the Arima-SV pipeline. To attribute clinical significance, we characterized fusions based on whether the fusion event involved a Tier 1 therapeutic level biomarker or a Tier 3 diagnostic or prognostic biomarker according to NCCN and OncoKb, or a Tier 2 biomarker if the biomarker was the target of a therapy in an ongoing clinical trial. Results: Hi-C detected fusions implicating a Tier 1 biomarker in 50% (7/14) of tumors, a Tier 2 level biomarker in 14% (2/14), and a Tier 3 level biomarker in 14% (2/14). Homologous recombination repair (HRR) gene rearrangements were detected in 29% (n = 4/14) of CRC tumors, disrupting HRR genes ( BRIP1, BRCA1, BRCA2, RAD51D). NRG1 gene fusions were detected in 14% (2/14), and amplified complex rearrangement carrying KRAS was detected in one CRC case. A complex rearrangement involving extrachromosomal DNA (ecDNA) amplification carrying EGFR was detected in two cases that were both previously found to have EGFR amplifications, but the ecDNA nature was not previously known and was confirmed by FISH. Lastly, Hi-C detected gene rearrangements involving POLE or APC in two CRC cases, alterations in which are known to increase risk for colonic polyposis. Conclusions: Fusion detection by Hi-C in CRC may uncover numerous therapeutic biomarkers not currently detected by molecular profiling. Our data suggests that homologous recombination deficiency (HRD) may frequently result from HRR gene rearrangements readily detectable by Hi-C, and this alternate mechanism for HRD may serve as a therapeutic biomarker for HRD directed therapies. Our data also suggests that therapeutically targetable gene fusions and complex rearrangements involving therapeutic level biomarkers are also readily detectable by Hi-C, detection of which may increase the number of CRC patients treatable with targeted therapies.

The Identification of Prenatal Exposure to Mitragynine Using Umbilical Cord Tissue

Objective: Kratom is widely available and literature exploring the effects of prenatal kratom exposure is lacking. This study aims to report a validated method for the detection of mitragynine in the umbilical cord and report our observations for specimens received at a national commercial reference laboratory. Study Design: Assays were validated according to the recommendations of ANSI/ASB. A retrospective evaluation of records at a national reference laboratory was conducted to determine prevalence and co-exposure to other substances of abuse. Result: Mitragynine was detected in 19 of 4456 specimens (0.43%) with concentrations ranging from 4 to >50 ng/g. Thirteen (13) of these specimens were positive for only mitragynine while the other 6 were also positive for either marijuana or opiates. Conclusion: Umbilical cord is a suitable specimen type for the surveillance of maternal kratom use and can be used to identify exposed neonates for further investigations into short- or long- term health consequences.

Cerebrospinal fluid AΒ42, total tau, and phosphorylated tau in the evaluation of Alzheimer’s dementia: Experience from a commercial reference laboratory

AbstractBackgroundAβ amyloid plaques and tau neurofibrillary tangles play an important role in Alzheimer’s disease (AD) pathophysiology, and the CSF biomarkers Aβ42, total tau (T‐tau), and phosphorylated tau181 (P‐tau) have been extensively used in diagnosing AD. Here we describe our experience with use of the Aβ42/T‐tau index (ATI) and P‐tau for classification of patients with suspected AD.MethodA convenience sample of results from CSF specimens submitted to a commercial reference laboratory for measurement of Aβ42, T‐tau, and P‐tau (presumably for diagnosis in patients with suspected AD) was selected for analysis. Each marker was measured using sandwich ELISA−based tests. The ATI was calculated as Aβ42/(240 + (1.18 × T‐tau)). AD classification was based a combination of ATI and P‐tau thresholds: not consistent with AD (not‐AD; P‐tau &lt;54 pg/mL and ATI &gt;1.2); borderline (P‐tau 54‐68 pg/mL and/or ATI 0.8‐1.2); AD (P‐tau &gt;68 pg/mL or ATI &lt;0.8); indeterminant—possible non‐AD dementia (NADD; ATI &lt;0.8, P‐tau &lt;54); and “other” (highly elevated ATI). Differences in age at testing among the classification groups were assessed using ANOVA with Tukey pairwise analysis.ResultResults from 42,030 specimens (49.1% women) were included. The most frequent classifications based on ATI and P‐tau values were AD (30.0%) and borderline (30.2%), followed by indeterminate‐NADD (21.7%), not‐AD (16.3%), and other (1.9%). Individuals with an AD classification were significantly older than those classified as not‐AD (mean [SD] age 66.8 [10.1] vs 62.5 [12.3] years; P&lt;0.001), and a higher proportion were female (55.6% vs 42.8%). The ANOVA model indicated significant differences in age at testing among the classification groups (P&lt;0.001). In post‐hoc pairwise comparisons, the not‐AD group was significantly younger than the AD group (Tukey multiple comparison test: difference= ‐4.3 years, Padj &lt;0.001). This pattern was consistent in analyses stratified by sex (women: difference=‐4.8 years, Padj &lt;0.001; men: difference= ‐4.4 years, Padj &lt;0.001).ConclusionNearly 30% of specimens submitted for AD testing yielded results consistent with AD, underscoring the value of the ATI and P‐tau measurements in CSF in patients with suspected AD. The greater age among those classified with AD vs non‐AD likely reflects the higher pretest probability of AD in older individuals.

Symmetric dimethylarginine concentrations in healthy neonatal foals and mares.

BackgroundSymmetric dimethylarginine (SDMA) is a renal biomarker correlated with glomerular filtration rate (GFR).ObjectivesDescribe changes in SDMA in clinically healthy foals and their mares during the first month postfoaling.AnimalsConvenience sampling of healthy periparturient Thoroughbred mares and their full‐term foals from a population of client‐owned horses.MethodsSerum and EDTA whole blood samples were collected from mares in their last month of pregnancy and then from mares and foals at approximately <12 hours, 48 hours, 7 days, and 30 days postbirth. Samples were processed at a commercial reference laboratory for CBC and serum biochemistry, including SDMA concentrations.ResultsA total of 125 foals and 104 mares were included. Upper limits for SDMA concentrations in foals were above the adult horse reference interval for the first 20 or more days of life. Median SDMA concentrations decreased from 70 μg/dL (range, 7‐100 μg/dL) to 18 μg/dL (range, 6‐27 μg/dL) during the first 3 to 4 weeks of life. At birth, the SDMA concentration reference range was established as 0 to 100 μg/dL (upper limit of the assay); 0 to 85 μg/dL for 1 to 4 days old, 0 to 36 μg/dL for 5 to 10 days old, and 0 to 24 μg/dL for 20 to 30 days old. The upper reference limits for SDMA concentrations in mares did not differ from the general reference interval for adult horses. No correlation was identified between mare and foal SDMA concentrations (ρ = .06, P = .58).Conclusions and Clinical ImportanceFoal SDMA concentrations remained higher than the upper limit of the adult reference range and foals require a different reference range dependent on age.

Four Human Cases of Eastern Equine Encephalitis in Connecticut, USA, during a Larger Regional Outbreak, 2019.

Abstract During 3 weeks in 2019, 4 human cases of Eastern equine encephalitis (EEE) were diagnosed at a single hospital in Connecticut, USA. The cases coincided with notable shifts in vector–host infection patterns in the northeastern United States and signified a striking change in EEE incidence. All 4 cases were geographically clustered, rapidly progressive, and neurologically devastating. Diagnostic tests conducted by a national commercial reference laboratory revealed initial granulocytic cerebrospinal fluid pleocytosis and false-negative antibody results. EEE virus infection was diagnosed only after patient samples were retested by the arbovirus laboratory of the Centers for Disease Control and Prevention in Fort Collins, Colorado, USA. The crucial diagnostic challenges, clinical findings, and epidemiologic patterns revealed in this outbreak can inform future public health and clinical practice.

Performance of Mumps PCR and Serologic Testing During a University-Associated Mumps Outbreak in Charleston, SC

Background: Sensitive diagnostic testing is critical in responses to mumps outbreaks. PCR testing of buccal swabs is the most sensitive diagnostic test, but IgM serology remains standard in much of the United States. We provided testing guidance stressing use of mumps PCR to ambulatory clinics and emergency departments in addition to the standard serologic testing for acute mumps beginning in 2018. We compared the performance of PCR and IgM serology to assess cases of parotitis presenting during a community outbreak of mumps in fall 2019 associated with a university in Charleston, SC. Methods: All patients tested for mumps who presented to our facility (ER and ambulatory clinics) with mumps PCR and/or mumps IgM ordered between September 2019 and January 2020 were included. Mumps PCRs were sent to a commercial reference laboratory (ARUP). Confirmed cases were defined as having a positive mumps PCR and/or IgM with parotitis. Clinical characteristics of mumps patients including age, duration of symptoms, MMR history, and association with the university were obtained by chart review. Results: Mumps was confirmed in 15 of 44 tested patients (34%), with 15 of 15 mumps patients (100%) having positive PCR and 1 of 15 patients (7%) and 1 of 15 patients (7%) having positive and equivocal mumps IgM serologies, respectively. Only 1 patient who did not meet our mumps case definition (no CT imaging evidence of parotitis, no fevers, chronic sinus symptoms) had a positive PCR and had recent receipt of a third MMR dose in response to the ongoing outbreak. Median age for mumps patients was 22 years (range, 15–48) with 8 of 15 cases (53%) detected among university students and an additional 2 cases having close connections to the university associated with the outbreak. Only 1 of 15 mumps patients (6.7%) was febrile at presentation (median temperature, 37.2°C) and mumps cases presented for testing ≤3 days for 7 of 15 cases (47%) (range, 0–13 days from symptom onset). No cases were diagnosed by IgM only, and 10 of 15 mumps cases had some recollection of remote MMR immunization, whereas 6 of 15 (40%) had 2 documented MMR doses at &lt;5 years of age. Conclusion: Serologic IgM testing for diagnosis of mumps appears insensitive for detection of cases in outbreaks within highly immunized adult patients. Although our recommended shift to PCR likely enhanced case finding during this outbreak, the potential for false-positive PCRs due to vaccine strain shedding following third-dose MMR immunization may also be considered a threat to the specificity of the test during outbreak situations.Funding: NoneDisclosures: None

Retrospective analysis of feline intestinal parasites: trends in testing positivity by age, USA geographical region and reason for veterinary visit

BackgroundThe goals of this retrospective study were to estimate parasite positivity in samples from cats using zinc sulfate fecal flotation by centrifugation (“centrifugation”) and coproantigen and examine trends with age, geographical region and reason for visit to veterinarian. Common methods of parasite detection, such as centrifugal flotation, passive flotation, or direct smear, may underrepresent the true prevalence of intestinal parasites in cats. Coproantigen testing detects more positive samples than traditional methods alone.MethodsFeline fecal test results from the continental USA containing results for fecal exams performed using centrifugation paired with coproantigen results for ascarid, hookworm, whipworm and Giardia were obtained from the database of a national commercial reference laboratory comprised of multiple regional sites.ResultsParasite positivity was highest in samples from young cats and decreased with cat age. The western region of the USA had lower total parasite positivity than other regions for all parasites except Giardia. Cats receiving fecal tests during veterinary wellness visits had only slightly lower parasite positivity than samples from cats during sick clinical visits.ConclusionsThis study showed a larger population of cats are at increased risk of parasitism than commonly believed and coproantigen testing produces more positive test results for the four parasites that antigen can detect than centrifugation of feline fecal samples.

Simultaneous quantitation of five triazole anti-fungal agents by paper spray-mass spectrometry.

Background Invasive fungal disease is a life-threatening condition that can be challenging to treat due to pathogen resistance, drug toxicity, and therapeutic failure secondary to suboptimal drug concentrations. Frequent therapeutic drug monitoring (TDM) is required for some anti-fungal agents to overcome these issues. Unfortunately, TDM at the institutional level is difficult, and samples are often sent to a commercial reference laboratory for analysis. To address this gap, the first paper spray-mass spectrometry assay for the simultaneous quantitation of five triazoles was developed. Methods Calibration curves for fluconazole, posaconazole, itraconazole, hydroxyitraconazole, and voriconazole were created utilizing plasma-based calibrants and four stable isotopic internal standards. No sample preparation was needed. Plasma samples were spotted on a paper substrate in pre-manufactured plastic cartridges, and the dried plasma spots were analyzed directly utilizing paper spray-mass spectrometry (paper spray MS/MS). All experiments were performed on a Thermo Scientific TSQ Vantage triple quadrupole mass spectrometer. Results The calibration curves for the five anti-fungal agents showed good linearity (R2 = 0.98-1.00). The measured assay ranges (lower limit of quantification [LLOQ]-upper limit of quantitation [ULOQ]) for fluconazole, posaconazole, itraconazole, hydroxyitraconazole, and voriconazole were 0.5-50 μg/mL, 0.1-10 μg/mL, 0.1-10 μg/mL, 0.1-10 μg/mL, and 0.1-10 μg/mL, respectively. The inter- and intra-day accuracy and precision were less than 25% over the respective ranges. Conclusions We developed the first rapid paper spray-MS/MS assay for simultaneous quantitation of five triazole anti-fungal agents in plasma. The method may be a powerful tool for near-point-of-care TDM aimed at improving patient care by reducing the turnaround time and for use in clinical research.

33. BLASTOCYST PLOIDY STATUS DEPENDS ON SPERM PARAMETERS

Introduction Aneuploidy is a very common abnormality in human embryos. The aneuploidy rates of blastocysts in IVF is in range 45-70% depending on different factors, including the male factor of infertility. Male infertility is diagnosed, among others, on the basis of quantitative or qualitative sperm anomalies visualized by semen analysis. On the other hand, the recent data about the effect of sperm on the blastocyst ploidy in IVF are controversial. The aim of our study was to evaluate the aneuploidy rate of the obtained blastocysts for patients with the severe male factor. Materials and methods In this study, the ploidy status of 229 blastocysts, obtained in 68 PGT-A cycles performed in 55 infertile couples with severe male factor from January 2018 to December 2018, with trophectoderm (TE) biopsy and next generation sequencing (NGS), were retrospectively analyzed. Totally 229 blastocysts with different morphology were biopsied and outsourced to commercial reference laboratory for NGS test. Correlation of blastocyst aneuploidy with sperm morphology, sperm concentration and sperm motility was evaluated with Spearman coefficient. Results The rate of euploid embryos was 65.5% (150 blastocysts). In the mentioned study 29.7% of examined blastocysts were aneuploid (68 embryos) and 4.8% of blastocysts were detected as mosaic (11 embryos). We evaluated the possible relationship between the sperm parameters and the NGS results for biopsied blastocysts taking into account the morphological quality of trophectoderm (TE) and intracellular mass (ICM). There was a significant positive correlation between the euploidy rates and sperm concentration (rs = 0.16, P 0.05). As for the correlation of NGS results with the blastocyst morphology, there was the significant positive correlation between TE quality and the number of euploid blastocysts (rS = 0.19, P 0.05). The analysis of the sperm effect on the blastocyst morphology showed a statistically significant positive link between sperm motility and morphological quality of TE and ICM (rs = 0.17, P Conclusion Existing data regarding the relationship between embryo morphology and its ploidy are conflicting. Results of the present study point to a significant relationship of the trophectoderm morphology with the chromosomal abnormalities in preimplantation embryos. The effect of male factor on the blastocyst ploidy status and blastocyst morphology is proved.

Distribution of the feline lungworm Aelurostrongylus abstrusus in the USA based on fecal testing.

ObjectivesThe aim of this study was to compile commercial reference laboratory data over a 10-year period to determine the distribution of Aelurostrongylus abstrusus, commonly known as feline lungworm, within the USA based on widespread fecal testing in cats.MethodsThe results of 3,610,455 feline ova and parasite (O&P) zinc sulfate centrifugation fecal flotation tests performed at IDEXX Reference Laboratories in the USA from January 2008 to December 2017 were compiled and sorted for tests positive for A abstrusus larvae. The results of 3625 Baermann tests, currently considered the gold standard diagnostic for feline lungworm, were also retrieved from the same period.ResultsOf the tests performed, 4721 (0.13%) feline O&P zinc sulfate centrifugation fecal flotation tests and 75 (2.07%) of the Baermann tests conducted were positive for the presence of A abstrusus larvae. The O&P data revealed a significant association between infection status and sex, while male cats in both the O&P and Baermann data sets had a higher risk of A abstrusus infection than females. Significant variation in positive rates were observed by region and most positive cases were clustered in the Northeast, Midwest and West regions of the USA.Conclusions and relevanceThis study highlights the distribution of feline lungworm in the USA and the limitations of using current testing to diagnose this infection. The introduction of higher throughput, less labor-intensive diagnostic methods could help increase awareness of this parasite among veterinary professionals, achieve a greater understanding of epidemiological factors, and improve the care and treatment for clinically ill feline patients.

Morphology of the blastocysts correlates with results of PGS

Introduction Embryo quality has always been considered an important predictor of successful implantation and pregnancy. However, knowledge of the relative impact of each morphological parameter needs to be increased, and this evaluation method has some limitations. Usually the morphologically high quality blastocysts are chosen for embryo transfer in IVF treatment. But the results of different authors about the correlation of embryo morphology with its aneuploidy are ambiguous. The aim of our study was to evaluate possible relationships among blastocyst ploidy status and standard morphology in PGS with next generation sequencing (NGS) in IVF cycles. Materials and Methods In this study, the morphology of 183 blastocysts, obtained in 53 PGS cycles performed in 45 infertile couples from April 2016 to December 2017, with trophectoderm (TE) biopsy and NGS, were retrospectively analyzed. Totally 183 blastocysts with different morphological quality were biopsied on the 5th and 6th days of culture and outsourced to commercial reference laboratory for next generation sequencing (NGS) test. Correlation of blastocyst morphology and embryo aneuploidy was examined with Spearman coefficient. Results In the mentioned study60.1% of examined blastocysts were aneuploid or mosaic (110 blastocysts). We evaluated the possible relationship between the morphology of blastocysts and PGS results taking into account the quality of trophectoderm and intracellular mass (ICM). There was no correlation between the quality of ICM and blastocyst ploidy (rs = 0.329, P > 0.05). But the decrease in quality of TE significantly correlated with the aneuploidy in blastocysts (rS = 0.458, P < 0.05). During the interpretation of women's PGS results the ploidy, aneuploidy and mosaicism were taken into account. The average age of patients'was 29.2±5.7 years old. No dependence of the blastocyst aneuploidy on the age was found in mentioned group. Conclusion Existing data regarding the relationship between embryo morphology and its ploidy are conflicting.Results of the present study point to a significant relationship of the trophectoderm morphology with the chromosomal abnormalities in preimplantation embryos. As no correlation between ICM morphology and blastocyst karyotype has not been found out the development of new approaches is relevant to choose the best embryo for the next PGS examination. Embryo quality has always been considered an important predictor of successful implantation and pregnancy. However, knowledge of the relative impact of each morphological parameter needs to be increased, and this evaluation method has some limitations. Usually the morphologically high quality blastocysts are chosen for embryo transfer in IVF treatment. But the results of different authors about the correlation of embryo morphology with its aneuploidy are ambiguous. The aim of our study was to evaluate possible relationships among blastocyst ploidy status and standard morphology in PGS with next generation sequencing (NGS) in IVF cycles. In this study, the morphology of 183 blastocysts, obtained in 53 PGS cycles performed in 45 infertile couples from April 2016 to December 2017, with trophectoderm (TE) biopsy and NGS, were retrospectively analyzed. Totally 183 blastocysts with different morphological quality were biopsied on the 5th and 6th days of culture and outsourced to commercial reference laboratory for next generation sequencing (NGS) test. Correlation of blastocyst morphology and embryo aneuploidy was examined with Spearman coefficient. In the mentioned study60.1% of examined blastocysts were aneuploid or mosaic (110 blastocysts). We evaluated the possible relationship between the morphology of blastocysts and PGS results taking into account the quality of trophectoderm and intracellular mass (ICM). There was no correlation between the quality of ICM and blastocyst ploidy (rs = 0.329, P > 0.05). But the decrease in quality of TE significantly correlated with the aneuploidy in blastocysts (rS = 0.458, P < 0.05). During the interpretation of women's PGS results the ploidy, aneuploidy and mosaicism were taken into account. The average age of patients'was 29.2±5.7 years old. No dependence of the blastocyst aneuploidy on the age was found in mentioned group. Existing data regarding the relationship between embryo morphology and its ploidy are conflicting.Results of the present study point to a significant relationship of the trophectoderm morphology with the chromosomal abnormalities in preimplantation embryos. As no correlation between ICM morphology and blastocyst karyotype has not been found out the development of new approaches is relevant to choose the best embryo for the next PGS examination.

A real-world, comparative study of FDA-approved diagnostic assays PD-L1 IHC 28-8 and 22C3 in lung cancer and other malignancies

AimsAt the time of analysis, two widely used, drug-specific, tumour-cell programmed death ligand 1 (PD-L1) assays were approved by the US Food and Drug Administration for anti-PD-1 therapies: the Dako...

Multiple Biomarker Testing Tissue Consumption and Completion Rates With Single-gene Tests and Investigational Use of Oncomine Dx Target Test for Advanced Non–Small-cell Lung Cancer: A Single-center Analysis

IntroductionFirst-line targeted therapies have been developed for advanced non–small-cell lung cancer (NSCLC). However, small biopsy samples pose a challenge to testing all relevant biomarkers. The present study characterized clinician-ordered single-gene lung cancer testing and evaluated tissue stewardship and the ability to successfully determine mutation status with single-gene testing or investigational use of the Oncomine Dx Target Test. Materials and MethodsClinician-submitted orders for 3659 single-gene tests (EGFR, ALK, ROS1, BRAF, KRAS, ERBB2, MET, RET, FGFR1) across 1402 samples at a large US-based commercial reference laboratory and 169 investigational Oncomine Dx Target Tests were retrospectively evaluated. The testing success rates and tissue consumption were evaluated by sample type, test type, and number of single-gene tests per sample. ResultsThe large majority of lung tissue samples submitted for clinical testing were small (70.5% core needle biopsies; 10.0% fine needle aspirations). With single-gene testing, mutation status was successfully reported for ≥ 1 biomarker for 88.4% of the clinical samples. The success rates decreased and tissue consumption increased with testing of additional biomarkers. Investigational Oncomine Dx Target Tests were permitted 1 tissue slide each and demonstrated success rates similar to single-gene testing for ≥ 5 biomarkers on core needle biopsies, ≥ 4 biomarkers on fine needle aspirations, and ≥ 2 biomarkers on surgical resection specimens. ConclusionTissue stewardship is important to enable successful completion of genetic testing and informed NSCLC treatment decisions. Preliminary assessment of the investigational Oncomine Dx Target Test suggests it could facilitate access to multiple biomarker testing using small tissue samples to support therapy decisions for patients with advanced NSCLC.

Development of a Commercial Reference Laboratory Elective Rotation for Residents in Clinical Pathology

To develop a curriculum for a commercial reference laboratory clinical pathology training elective. A 4-day elective at Quest Diagnostics was developed. The elective included 32 sessions composed of interactive didactic sessions and laboratory tours/demonstrations. Ten residents who attended the elective completed a written evaluation and scored each component of the curriculum. Written comments were very positive and demonstrated the goals of the elective were achieved. Laboratory tours and one-on-one sessions with the medical directors were especially well received. Most of the residents stated that the rotation gave them exposure to an area of laboratory medicine that they were not familiar with. The elective provided a resident training experience that was highly regarded and exposed residents to an area of laboratory medicine not encountered in most pathology training programs. Our curriculum could serve as a model for establishing a similar elective in other training programs.

The Impact of Disruption of the Care Delivery System by Commercial Laboratory Testing in a Children's Health Care System.

Disruption of outpatient laboratory services by routing the samples to commercial reference laboratories may seem like a cost-saving measure by the payers, but results in hidden costs in quality and resources to support this paradigm. To identify differences when outpatient tests are performed at the Children's Healthcare of Atlanta (Children's) Hospital lab compared to a commercial reference lab, and the financial costs to support the reference laboratory testing. Outpatient testing was sent to 3 different laboratories specified by the payer. Orders were placed in the Children's electronic health record, blood samples were drawn by the Children's phlebotomists, samples were sent to the testing laboratory, and results appeared in the electronic health record. Data comparing the time to result, cancelled samples, and cost to sustain the system of ordering and reporting were drawn from multiple sources, both electronic and manual. The median time from phlebotomy to result was 0.7 hours for testing at the Children's lab and 20.72 hours for the commercial lab. The median time from result posting to caregiver acknowledgment was 5.4 hours for the Children's lab and 18 hours for the commercial lab. The commercial lab cancelled 2.7% of the tests; the Children's lab cancelled 0.8%. The financial cost to support online ordering and reporting for testing performed at commercial labs was approximately $640,000 per year. Tangible monetary costs, plus intangible costs related to delayed results, occur when the laboratory testing system is disrupted.

Abstract 128: A Precision Medicine Test Accurately Rules Out Obstructive Coronary Artery Disease Among Non-Diabetic Patients Presenting to Emergency Department With Acute Chest Pain

Background: An age, sex, and blood gene expression score (ASGES) has been previously validated to detect obstructive coronary artery disease (CAD) in non-diabetic patients presenting with stable chest pain in the outpatient setting. However, the diagnostic performance of this test in ruling out obstructive CAD in patients presenting with acute chest pain (ACP) to the emergency department (ED) is unknown. Methods: In an ongoing study, 371 low-intermediate risk patients with ACP and no prior history of CAD (TIMI risk score ≤ 2, negative troponins and normal/non-diagnostic ECG) underwent coronary CT angiography (CCTA) using institutional protocols. Patients were classified based on severity of stenosis (obstructive CAD, &gt;50%; high grade stenosis, &gt;70%) and ASGES. The ASGES blood test sample was drawn before ED discharge and analyzed in a commercial reference laboratory (Redwood City, CA). We excluded 23 (6%) patients with unreportable ASGES and 47 (13%) diabetics from this primary analysis. Results: 301 (53±10 years, 45% males, 78% Hispanics) non-diabetic ACP patients undergoing CCTA in an ED setting were included in this analysis. No plaque was detected in 183 (60%) patients, and 22 (7%) patients had obstructive CAD. In this population, 51% of patients had scores below the previously defined threshold of ASGES≤ 15. This threshold yielded sensitivity, specificity, NPV, and PPV of 71% (52-86%), 53% (47-59%), 97% (93-98%), and 12% (9-14%) for obstructive CAD. Furthermore, ASGES≤15 yielded a 100% sensitivity and NPV for patients with high grade stenosis (n=7, 2%). In a multivariable analysis including patient demographics and clinical covariates, ASGES ≤15 was significantly associated with obstructive CAD (OR: 0.15, 95% CI: 0.04-0.62). As a continuous variable, increasing ASGES was positively correlated with the presence of obstructive CAD and CCTA-defined plaque burden (p&lt;0.0001). Conclusions: This is the first study validating the use of this blood-based precision medicine test to rule out obstructive CAD among low-intermediate risk non-diabetic patients presenting with ACP in ED setting. 30-day follow-up is underway to evaluate the prognostic implications of these findings.