A-207 Investigating an Increase in Specimen Recollection Rates Due to Hemolysis After a Testing Location Change: The Impact of Specimen Type and Patient Population
Abstract Background The Oncology Department at our institution requested faster turn-around times (TAT) for chemistry testing. Prior to their request, serum separator tubes (SST) were collected and tested in our core laboratory. To accommodate the request, we added plasma total bilirubin and aspartate aminotransferase (AST) to our stat laboratory test menu with collection in plasma separator tubes (PST). Upon implementation of this testing change, we observed an increase in specimen recollection rates due to hemolysis. We systematically evaluated laboratory testing variables that could have contributed to the increase: pneumatic tube transport path, differences in hemolysis measurements between chemistry analyzer models, and specimen types. Previous studies have demonstrated that lithium heparin plasma specimens are more susceptible to hemolysis than serum. Likewise, patients undergoing chemotherapy or radiation therapy may have fragile red blood cell (RBC) membranes, further complicating the issue. Our study*s objective was to assess the impact of changing from SST to PST collections. We conducted a 3-month pilot study to determine if we could reduce our recollection rates by collecting/testing Rapid Serum Tube (RST), while maintaining plasma TAT. Methods We compared recollection rates for specimens collected from the oncology patients and tested in our core laboratory (SST, May-June 2021), stat laboratory (PST, September-November 2022), pilot period in stat lab (RST, January-March 2023), and post-pilot period in stat lab (PST, May-July 2023). Data were extracted from our laboratory information system and recollection rates were calculated using Tableau (Salesforce, Inc, San Francisco, CA). Analysis was performed in Excel (Microsoft, Redmond, WA) using Student’s t-test, with p < 0.05 defined as statistically significant. Results SST specimens collected from oncology patients and tested in the core lab (May-June 2021) resulted in a recollection rate of 0.17% (4/2341). PST specimens sent to the stat lab (Sept-Nov 2022) had an increased recollection rate of 0.90% (55/6129, p-value < 0.001). During the pilot period when RST tubes were used (Jan-Mar 2023), our recollection rate decreased to 0.19% (11/5801, p-value 0.014). After the pilot period ended and PST tubes were again utilized for testing (May-July 2023), the recollection rate again increased to 0.34% (22/6500, p-value 0.019). Conclusion Rapid TAT of laboratory results within specialized-care settings, such as a cancer treatment clinic, is necessary to provide patients with the most effective and personalized treatment regimens. Hemolysis presents a challenge as it generates an analytical issue with the release of contents from RBCs that may spuriously affect the concentration of the analyte being measured, delaying result reporting due to the need for specimen recollection. The data from our study highlight the utility of rapid serum tubes. Not only did they achieve stat TAT that was observed with the use of PST, but they also decreased specimen recollection rates that mirror the low rates observed with the use of SST. Thus, this technology may be an excellent replacement for standard SST when specimen integrity is critical to rapidly reporting accurate test results.
A-193 It Started with Tape: Empowering Technologists on a Journey of Innovation and Safety in Cryoglobulin Testing
Abstract Background Cryoglobulins are immunoglobulins that precipitate at cold temperatures. They are associated with plasma cell disorders, infectious and autoimmune diseases. Laboratory testing is manual and requires strict temperature control, from keeping the blood sample warm from the moment of draw until processing in the laboratory. Serum samples are transferred to Kolmer glass graduated tubes upon arrival, and kept on ice for visualization of a precipitate for up to 7 days. Because of the temperature variation samples are subjected to, positive sample identification is important. The Kolmer glass tubes are not disposable, and undergo several steps of deidentification and cleaning for reuse. The goal of this project was to improve patient safety and label adherence in cryoglobulin testing by using the Managing for Daily Improvement (MDI) method to monitor and implement changes effectively. Methods During a Plan Do Study Act (PDSA) initiative, it was discovered that labels were not being secured on both ends with tape due to safety concerns when using a box cutter to remove the label prior to cleaning. This practice led to an increase in labels detaching from the glass tubes. To address this issue, we employed the MDI method and established a Key Performance Indicator (KPI) to monitor and evaluate potential changes aimed at improving label adherence. The MDI method facilitates problem-solving through daily visual indicators and discussions by empowering technologists to identify and address issues affecting daily operations. This approach encourages open communication and collaborative problem-solving, allowing the entire team to share insights and solutions in real time. Results A PDSA initiative via MDI uncovered the label adherence challenges. A KPI was developed to monitor interventions to improve the process. First, removable tape was used to secure both sides of the label. Initial results were worse than the original method but slight improvement occurred at about 3 weeks. A Just Do It (JDI) approach was initiated to leave additional space between samples. No improvements were observed and the practice discontinued within < 2 weeks. A second JDI was trialed with a different tool to remove labels post-use. The entire sample identification process was reviewed and the original identification process resumed, by adding scotch tape securing both sides of the labels and using a ceramic box cutter to remove the labels. Significant improvements to labels adherence was observed, from about 60% of labels coming off to zero, while the new tool was also safer for the team. Another PDSA was initiated to investigate if plastic, disposable tubes were a viable option for testing, and a full method validation of the new plastic tubes followed, finally eliminating the challenges with the larger process or reusing glass tubes. Conclusion MDI helped recognize a problem from the front-line and find real time solutions that benefited end-to-end operations. Visual daily indicators clearly showed effectiveness of interventions. Identifying real issues, even if they appear small, can lead to improved patient and staff safety, and empowerment to initiate meaningful change.
A-173 Evaluation of Plateletworks and TEG 6S Platelet Mapping: Performance Characteristics and Differentiation of Healthy Donors from Patients on Dual Antiplatelet Therapy
Abstract Background Platelet function tests (PFT) help assess bleeding risk and guide appropriate hemostatic measures in patients on antiplatelet therapy undergoing emergent surgical interventions. Light transmission aggregometry (LTA, BioData Corporation), the gold standard for assessing platelet function, cannot be performed rapidly enough for emergent interventions. In this study, we compared two PFT, Plateletworks (Helena Laboratories) and TEG 6S (TEG, Haemonetics) adenosine diphosphate-(ADP) and arachidonic acid (AA)-induced platelet function, evaluating analytical imprecision and their ability to differentiate healthy controls from patients with acute coronary syndrome (ACS) on dual antiplatelet therapy. Methods Fresh specimens were collected from healthy donors (HD, N=19) and a patient group (PG, N=17) on both aspirin and clopidogrel taken within 24 hours of procedure. Percent aggregation was measured according to manufacturers’ instructions using Plateletworks and TEG, utilizing both AA and ADP and compared to LTA performed on a PAP-8E Platelet Aggregometer. Two separate venipuncture collections from HD were used to obtain repeat measures of Plateletworks and TEG to assess variability in platelet function due to pre-analytical variables. Using a two-way nested ANOVA model on data from HD, we estimated variability between replicates of a single sample (intra-assay imprecision) and between blood draws within a single patient (inter-assay imprecision), reported as coefficient of variation (CV%). Platelet function results were summarized as median (interquartile range [IQR; 25th-75th percentiles]) and compared between groups using nonparametric Wilcoxon rank-sum test. Receiver operating characteristic (ROC) analysis (using duplicate means from first blood draw) was performed. Results Plateletworks AA % aggregation, medians (IQR) were 96.3 (95.3-97.1) for HD and 48.9 (46.8-54.8) for PG (p<0.001); ADP % aggregation were 97.0 (94.5-98.2) and 37.1 (28.0-53.0) for HD and PG, respectively (p<0.001). TEG AA % aggregation was 97.8 (94.4-99.8) for HD and 13.5 (7.9-26.8) for PG (p<0.001); ADP % aggregation was 98.3 (95.3-99.9) for HD and 83.3 (77.8-87.7) for TG (p<0.001). LTA AA % aggregation was 55.0 (44.0-64.8) for HD and 0.0 (0.0-1.5) for PG (p<0.001); ADP % aggregation of 59.0 (40.8-70.8) and 14.5 (4.5-19.5) for HD and PG, respectively (p<0.001). Intra- and inter-assay imprecision estimates (CV%), respectively, in HD were 1.4 and 5.1 for Plateletworks AA, 5.5 and 15.9 for Plateletworks ADP, 3.0 and 0.0 for TEG AA, and 2.6 and 0.8 for TEG ADP. Intra-assay precision estimates for LTA AA and LTA ADP were 19.3 and 8.2. In PG, intra-assay precision was estimated as 7.0 for Plateletworks AA, 9.6 for Plateletworks ADP, 61.3 for LTA AA, 11.9 for LTA ADP, 37.6 for TEG AA, and 4.1 for TEG ADP. In our limited data set, ROC analysis showed optimal cutpoints (sensitivity/specificity) for Plateletworks AA 65.5 (1.0/1.0) and ADP 84.5 (1.0/0.90), TEG AA 87.1 (1.0/1.0) and ADP 92.7 (1.0/1.0), and LTA AA 8.75 (0.94/1.0) and ADP 25.0 (0.82/0.90) Conclusion Plateletworks most effectively distinguished % aggregation between healthy donors and patients on dual antiplatelet therapy. TEG also differentiated the groups, but differences in median ADP-induced aggregation were smaller than with Plateletworks. Both AA and ADP assays on LTA showed more variability than either Plateletworks or TEG.
A-112 Differential effects of chronic kidney disease on circulating concentrations of phosphorylated tau and beta amyloid Alzheimer’s Disease blood biomarkers
Abstract Aims Blood biomarkers (BBMs) are promising minimally invasive tools for the evaluation of Alzheimer’s disease (AD). However, recent studies have demonstrated that comorbidities, such as severe chronic kidney disease (CKD), may elevate circulating concentrations of various BBMs including amyloid-ß (Aß) and phosphorylated tau proteins (p-tau). Previous work has found that the effects of CKD on BBM plasma concentrations could be partially mitigated through use of biomarker ratios (e.g., the proportion of p-tau217 to non-phosphorylated tau217 (np-tau217)). In this work, we quantitatively evaluate how different combinations of BBM ratios and single biomarkers are affected in the context of decreased kidney function. Methods Participants (n=83, >57 years of age) with CKD stages 1-2 (eGFR 60-98, n = 50), and stages 3-4 (eGFR 25-59, n = 33) and without amyloid pathology (A-) were included. eGFR (mL/min/1.73 m2) was calculated using the 2021 CKD-EPI equation based on serum-paired creatinine measurements. Plasma p-tau217, np-tau217, p-tau181, np-tau181, Aß42, and Aß40 were measured by mass spectrometry (MS) (C2N Diagnostics). %p-tau217 [(p-tau217/np-tau217) x 100], %p-tau181 [(p-tau181/np-tau181) x 100], Aß42/Aß40 ratio, and p-tau217/Aß42 ratio were calculated. Log-Log (power function) best-fit regression analysis was used to quantitatively predict the relationship of BBM changes as a function of eGFR. Results Median concentrations of p-tau217, np-tau217, p-tau181, np-tau181, Aß42, and Aß40 were all significantly elevated in individuals with eGFR <60 mL/min/1.73 m2 compared to those with eGFR > or =60 (all p < 0.05). There were no differences in the %p-tau217 and Aß42/Aß40 median values between these two groups (eGFR <60 versus > or =60) (p > 0.05); whereas the proportions %p-tau181 and p-tau217/Aß42 median values were higher in the eGFR > or =60 group versus the <60 subset. Observed best-fit analyte regression equations of eGFR versus BBM concentrations predict that an eGFR decrease from 60 to 45 results in p-tau217 and p-tau181 increases of 52% (95% confidence interval (CI): 30–78%) and 40% (95% CI: 29–53%), respectively. A 16% (95% CI: 12–21%), and a 19% (95% CI: 16–23%) increase was predicted in response to the same eGFR decline for Aß42 and Aß40. Furthermore, increases of 19% (95% CI: 2–38%) for %p-tau217, 6% (95% CI: -0.02–13%) for %p-tau181 and 31% (95% CI: 12–53%) for p-tau217/Aß42 were predicted as eGFR declined from 60 to 45, while a minor decrease of 2.3% (95% CI: -5.2–0.6%) was predicted for Aß42/Aß40. Conclusions: Reduction in eGFR is associated with significant elevations in plasma concentrations of p-tau217, p-tau181, Aß42, and Aß40, which may affect the interpretations of these biomarkers. However, the use of %p-tau217, %p-tau181, or p-tau217/Aß42 could partially attenuate this effect. Although the Aß42/Aß40 ratio is not considered an effective diagnostic BBM for AD, this ratio was relatively unaffected by CKD. For example, in comparison to p-tau217 alone, using %p-tau217 or p-tau217/Aß42, the relative increase in analyte values associated with decreased eGFR was reduced by 63% and 40%, respectively. These findings provide a better understanding of the effect of reduced eGFR on AD BBM interpretation in the presence of CKD.
A-085 Clinical Consequences of lack of Standardization/Harmonization of Ferritin Assays
Abstract Background The lack of standardization and harmonization among ferritin assays results in significant variability in clinical values. These assays have different reference ranges and numerous clinical cut-offs for interpreting anemia and iron toxicity. This inconsistency is due to manufacturers using various calibrators. Such variability complicates the interpretation and comparison of results across different clinical settings. Methods Ferritin was ordered for 7815 patient samples in 3 months and assays were performed by DXI. Similarly, 5818 patients’ samples were run by Roche in two months. Both assays are FDA cleared and are commonly used by hundreds of clinical laboratories. Frequency of no of patients flagged low or flagged were calculated with respective reference ranges of Dxi and Cobas. Results 12 percent of the patients were flagged low by the Beckman assay and would have gotten both physician and patients attention. However, by the Roche assay only 4 percent were flagged low. This was alarming to our physicians and lab was told to investigate to find for this shift. Manufacturer/Time Range Total Volume Total High Total Low %High %Low Dxi-May-24 2617 368 326 14.1% 12% Dxi-Jun-24 2391 345 278 14% 12% Dxi-Jul-24 2807 500 308 17.8% 11% Cobas-801 August 2024 - Ferritin Go Live Cobas-801-Sep-24 2545 572 105 22% 4% Cobas-801-Oct-24 2841 695 121 24% 4% Conclusion Lack of Standardization and harmonization has serious consequences for the patients being tested for ferritin to diagnose deficiency of iron or high iron situations. We are planning to do a prospective study to determine clinical cut-offs by correlating Ferritin lab results with other gold standard biomarkers including bone marrow biopsy.
A-082 Prevalence of Vitamin D2 Toxicity in American Population
Abstract Background Vitamin D supplementation by human individuals has significantly increased in the world. In US the total stored 25-OH-Vitamin D3 and 25-OH-Vitamin D2 has significantly increased for both in summers and winters. Under sunlight exposure, 7 dehydrocholesterol is converted to Vitamin D3 and is endogenous source in mammals. However, most of the exogenous source for Vitamin D used to be Vitamin D2 which used to be extracted only from mushrooms but is now manufactured by supplement industry as well. In last decade most of the supplementation has been due to chemically synthesized Vitamin D3. Food is now supplemented by both D2 and D3. It is not clear what is the prevalence of D2 supplementation/consumption in American population. Competitive immunoassays do not consistently recover 25-OH-D2 compared to 25-OH-D3 and some antibodies used have variable or no cross reactivity with 25-OH-D2. LC-MS/MS method can easily distinguish the two and can help in providing the precise and accurate results for 25-OH-D2 and 25-OH-D3. Here we present what is the prevalence of Vitamin D2 consumption and toxicity in American population based on our LC-MS/MS methods. Methods The study measured vitamin 25-OH-D levels (total, D2, and D3) in 148,654 patients from Mayo Clinic as well as from other medical centers within the U.S. Patients age ranging from new-born babies to over 100 years, and represents Male, Female and Neutral genders. Samples were analyzed for 25-OH-Vitamin D by LC-MS/MS as published earlier. Unlike immunoassays, LC-MS/MS gave us separate results for 25-OH-D3 and 25-OH-D2 with 100 percent specificity. Results 25-OH-Vitamin D2 levels of greater than 10 was present in at least 10,358 and ranged from 10 to 205 ng/mL. Of 10,358, 51 percent had 20-50 ng/mL, 10 percent had 51-80 ng/mL, and 1.3 percent had >80 ng/mL, ranging from 81-205 ng/mL with a median of 92 ng/mL. Of the patients found at Total Vitamin D >80 ng/mL, toxic levels of both D2 and D3 were found more in females than males. There was no significant gender difference for Vitamin D3 consumption but for D2 consumption, mean and median levels were different in males and females. Conclusion Clinical lab testing should accurately measure both 25-OH-D3 and 25-OH-D2, otherwise the patient total Vitamin D values in circulation will be underestimated.
A-069 Comparison of Three Hemoglobin A1c Methodologies in Variant and Non-Variant Samples
Abstract Background Hemoglobin A1c is used to assess glycemic control to both diagnose and monitor diabetes mellitus. Several different methodologies are available including high performance liquid chromatography (HPLC), capillary electrophoresis (CE), and immunoassay (IA). These methods are standardized and traceable to the Diabetes Control and Complications Trial (DCCT). The aim of this study was to evaluate the difference in HbA1c results between methods and percent of reportable results in variant samples. Methods The HPLC (Bio-Rad Laboratories, Inc; D-100), the CE(Sebia Inc; Capillarys 3), and IA(Roche Diagnostics Inc; Tina-quant Generation 3) were compared using two sets of residual patient samples left after physician ordered testing was complete: 1) samples with an absence of abnormal hemoglobin peaks (i.e. non-variant) detected by HPLC; 2) samples with abnormal hemoglobin peaks (i.e. variant) characterized by hemoglobin electrophoresis performed clinically or lacking an A1c peak by HPLC/CE. The samples were tested within manufacturers stability claims. 317 non-variant samples were compared between the HPLC and CE methods. The absolute difference was calculated for each method using this equation (HbA1c%avg – HbA1c%X) where HbA1c%avg is the average of the methods that produced reportable results and X is the result from each method evaluated. Differences less than or equal to +/-0.3% were considered acceptable. 28 of the 317 non-variant and 47 variant samples were tested by all 3 methodologies. The 47 variant samples grouped into 3 cohorts: common heterozygous variants (HbC, HbD, HbE, HbS and HbF, n=10), uncommon heterozygous variants (n=29) and homozygous variants lacking HbA (n=8). The absolute differences in variant sample results were calculated for samples that did not surpass manufacturer’s claims for producing an accurate result. The frequency of producing a numeric result in variant samples was calculated for each method. Results The HPLC/CE non-variant sample comparison (N=317) had results spanning the measuring range (3.8% - 14.0%) with average(range) of absolute difference=0.1(-0.4to0.6%) with 293/317(92.4%) samples within +/-0.3%. The HPLC/CE/IA non-variant sample comparison (N=28) had a result range=4.0%-9.4%, the average(range) of difference=0.1(-0.2to0.5%) with 25/28 (89.2%) of samples within +/-0.3%. Common heterozygous variant samples gave numeric results with no disqualifying flags in 9 of 10(HPLC), 8 of 10(CE), and 9 of 10(IA) samples tested. The average(range) difference from average=0.0(-0.3,0.5%) for HPLC, 0.0(-0.2,0.3%) for CE, and -0.1(-0.6,0.2%) for IA. Uncommon variant samples gave results in 4 of 29 (HPLC), 20 of 29 (CE), and 26 of 29 (IA) of samples tested. The average(range) difference from average=-0.1(-0.3,0.1%) for HPLC, 0.0(-1.0,1.1%) for CE, and 0.0(-1.1,1.0%) for IA. The homozygous variant (no HbA) samples gave results in 0 of 8 (HPLC), 0 of 8 (CE), and 4 of 8 (IA) of those tested. Conclusion All three methods meet their claims for accurately measuring hemoglobin A1c from non-variant and common hemoglobin variants. The advantage of HPLC and CE is the ability to identify hemoglobin variants that may impact HbA1c quantitation. The IA method provides the most numeric results. IA gave results even when HbA was absent. The lab should understand the capabilities and limitations of their HbA1c method on the population served.
Adding employment status in the medical record demonstrates its importance as a social determinant of health
Abstract Objective To share findings of a quality improvement initiative to capture employment status in the electronic medical record (EMR) to mitigate the potential impact of work loss on the health of patients by utilizing the results to identify eligible individuals for resources to assist return-to-work efforts. Materials and Methods Patients self-identified employment status through a structured new social determinants of health (SDOH) question within the EMR. An electronic outreach campaign was developed to provide information via the patient portal detailing services within healthcare and the community that could benefit the patients. Results Over the course of 12 months, 2059 patients were identified from the employment SDOH question. Resources to support stay at work and return to work efforts were provided to patients through an automated electronic portal campaign with 87% of patients reading the message and 7% engaging with a healthcare return to work case manager. Discussion Loss of employment has detrimental impacts on individual and population health. Most EMRs do not capture information on employment status. Adding this simple question identified individuals with potential gaps in SDOH, and in this case allowed specific resources to be shared with patients with an illness or injury that was acutely impacting work. Conclusion Medical center decision makers and EMR programmers should consider adding employment status as a social determinant of health.
Characterization of Spirometric Response to Standard-of-care Treatment in Lung Allograft Recipients With Bronchiolitis Obliterans and the Utility of Spirometric Criteria for Rescue Therapy: Implications for the Design of Risk-stratified Clinical Trials
Background. The spirometric response to standard-of-care (SOC) immunosuppressive therapy for the management of bronchiolitis obliterans syndrome (BOS) has been sparsely reported in the literature. Data from a Medicare-approved Registry were analyzed to characterize the effectiveness/durability of a wide range of SOC interventions to manage the decline of lung function and to validate the study spirometric criteria for initiation of rescue therapy. Methods. Lung transplant recipients with refractory BOS at 21 US collaborating centers were enrolled in the Registry. Data included both nonspirometric (eg, demographic, Immunosuppressive Regimens for management of BOS) and spirometric parameters (ie, forced expiratory volume in 1 s [FEV 1 ] measurements and derived indices). The utility of study FEV 1 criteria for treatment (ie, statistically significant rate of FEV 1 decline >30 mL/mo) was evaluated by comparing the spirometric course between participants who met or did not meet this criterion. Results. Only 21% of participants treated with SOC therapy had >50% decrease (76 ± 25% decrease) in the rate of FEV 1 decline. Although 51% of participants had a partial response (rate of FEV 1 decline decreased on average 71%), 49% of participants had a substantial increase (mean increase 224%). The FEV 1 criterion for treatment was able to identify 19% of participants (48/258) who achieved durable stabilization (ie, nonsignificant rate of FEV 1 <30 mL/mo) with SOC therapy. Conclusions. Patients with BOS have a widely variable response to SOC therapy. Our findings support the use of FEV 1 rate of decline to assess response to SOC therapy and to ensure appropriate assignment of participants with refractory BOS to rescue therapy treatment cohorts.
Monoclonal Gammopathy of Undetermined Significance