Citations

Abstract Background Hemolysis, a common pre-analytical interferent in clinical laboratory testing, can significantly affect accuracy and reliability of laboratory results. One test particularly susceptible to interference is direct bilirubin (D-bil). For example, during December 2024, 40% (500/1239) of specimens rejected due to hemolysis were orders for D-bil. The recently released Roche (Roche Diagnostics) direct bilirubin reagent (BILD2) has a lower threshold for hemolysis (H-index [HI]=25)) than the previous generation (HI=30). The aims of our study were to (1) establish concentration-specific hemolysis thresholds for D-bil and (2) investigate the instrument’s reduced volume function (dilution) as a possible mitigation strategy for samples with hemolysis indices exceeding the established thresholds. Methods Residual serum specimens from physician-ordered D-bil testing were used and analyzed on Roche cobas c701 and c501 analyzers. The instrument’s decreased volume function, intended for results outside the measuring range, was used as a 1:2 dilution and validated using 9 non-hemolyzed negative control specimens with D-bil results from 9.8-13.4 mg/dL. Recovery within 10% neat value was considered acceptable. EDTA whole blood was used to prepare hemolysate pools by washing red cells and lysing by freezing (-80 °C). Twenty-six serum pools with varying D-bil concentrations (0.2-3.4 mg/dL) were prepared. Each pool was split into 10 aliquots and spiked with increasing amounts of hemolysate, not exceeding 10% serum to interferent ratio. The decreased volume function (dilution) was utilized on a subset of the hemolysate-spiked aliquots (N=55) with D-bil results from 0.2-2.5 mg/dL. HI values were estimated to be 50% of neat HI due to the instrument’s inability to measure indices on specimens tested with the decreased volume function. Acceptance criteria for experiments utilizing hemolyzed specimens were ±0.1 mg/dL or 20% of neat sample. Results All non-hemolyzed specimens tested with the decreased volume function passed within acceptance criteria with average recovery of 109% (range: 106-110%) from undiluted specimens. Serum pools with D-bil <0.3 mg/dL (N=7) spiked with hemolysate (HI range: 7-191) had an average difference of -0.1 mg/dL (range: -0.2-0.0 mg/dL) from non-hemolyzed pools, D-bil pools 0.4-0.9 mg/dL (N=10; HI range: 6-173) had an average difference of -0.2 mg/dL (range: -0.5-0.0 mg/dL), and D-bil pools >1.0 mg/dL (N=9; HI range: 5-182) had an average difference of -20.7% (range –45.5-0.0%). Serum pools with D-bil <0.3 mg/dL (N=23; HI range: 43-191) tested using the decreased volume function had an average difference –0.1 mg/dL (range: -0.2-0.0 mg/dL; HI range: 22-96) from the non-hemolyzed specimens, D-bil pools 0.4-0.9 mg/dL (N=20; HI range: 39-173) had an average difference -0.1 mg/dL (-0.3-0.0 mg/dL; HI range: 19-86), and D-bil pools >1.0 mg/dL (N=12; HI range: 37-182 ) had an average difference of -0.2 mg/dL (-0.5-0.2 mg/dL; HI range: 19-91). Conclusion We established a new hemolysis interference threshold of 75 for samples with D-bil <0.3 mg/dL. Using the decreased volume function, we expanded the hemolysis interference threshold to HI=100 for specimens =0.3 mg/dL. All specimens with HI>100 will result in a recollection. With these changes, we estimate that we can reduce our D-bil recollections by up to 6% over six months.

Abstract Background Community Paramedic (CP) programs use specially trained paramedics to provide healthcare in the community to increase access to care, reduce unnecessary emergency department visits, and improve timeliness of care. Mayo Clinic in Rochester, MN recently launched a CP Program to provide in-home care for patients who require regular intravenous medications, wound care, diuresis for heart failure, medication reconciliation, care plan compliance/education. CP utilizes i-STAT1 CHEM8+ and Lactate (CG4+) testing (Abbott Point of Care, Abbott Park, IL) to make therapy decisions primarily for heart failure patients based on rapid laboratory results. Having results available at the point of care (POC) eliminates delays between testing and treatments, expediting care for the patient. Prior to using i-STAT, CP traveled to the patient’s residence, drew blood tubes, delivered the tubes to Mayo Clinic, waited for test results, returned to the patient’s home, and provided treatment. In this observational study, we assessed the benefit of in-home POC i-STAT1 testing performed by our CP Program to improve patient care and increase efficiency. Methods Patients within a 40-mile radius of Mayo Clinic were eligible to receive CP service. Whole blood venous specimens were collected and tested using the i-STAT1 CHEM8+ metabolic panel cartridge according to manufacturer instructions to measure: ionized calcium, chloride, glucose, hematocrit, total carbon dioxide, blood urea nitrogen, creatinine, potassium, sodium, anion gap while the i-STAT1 CG4+ cartridge measures lactate. The laboratory information system was used to extract laboratory results, and Excel (Microsoft, Redmond, WA) was used to filter data and perform calculations. Results November 2022 through December 2024, CP performed testing with 353 i-STAT cartridges (3862 tests) on 102 unique patients who each had 1-12 separate orders. Patient ages were 25 to 97 years. 41.2% (1590/3862) of the individual results obtained were outside of our reference intervals (23.0% high, 18.0% low), with 10.8% being ionized calcium, 10.2% chloride, 10.3% glucose, 13.0% hematocrit, 7.6% total carbon dioxide, 18.2% blood urea nitrogen, 16.4% creatinine, 6.7% potassium and 6.9% sodium. Additionally, 0.13% of results were critically high (ionized calcium, potassium, and sodium) and 0.10% were critically low (potassium and ionized calcium). Hypokalemic patients were sent to the infusion therapy center for IV potassium. Patients experiencing hyperkalemia were retested and sent to the emergency department (ED). Hyponatremic and hypercalcemic patients were sent to the ED for further treatment. Abnormal (non-critical) results were reviewed by CP personnel to make treatment recommendations or medication adjustments. Conclusion i-STAT1 home testing performed by CP facilitated rapid therapeutic interventions and expedited decision-making. POC testing has increased the group’s efficiency—alleviating the need to transport specimens to the central laboratory and wait on test results before returning to the patient for treatment. Paramedicine emphasizes a proactive and preventative approach to medicine. We anticipate that this model of care and testing will expand to cover other chronic health conditions due to the program’s early success.

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.

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.

Metabolic dysfunction–associated steatohepatitis (MASH) is a progressive liver disease characterized by complex interactions between lipotoxicity, ER stress responses, and immune-mediated inflammation. We identified enrichment of the proinflammatory alarmin S100 calcium-binding protein A11 (S100A11) on extracellular vesicles stimulated by palmitate-induced lipotoxic ER stress with concomitant upregulation of hepatocellular S100A11 abundance in an IRE1A-XBP1s–dependent manner. We next investigated the epigenetic mechanisms that regulate this stress response. Publicly available human liver ChIP-Seq GEO datasets demonstrated a region of histone H3 lysine 27 (H3K27) acetylation upstream of the S100A11 promoter. H3K27 acetylation ChIP-qPCR demonstrated a positive correlation between lipotoxic ER stress and H3K27 acetylation of the region, which we termed the lipotoxicity-influenced enhancer (LIE) domain. CRISPR-mediated repression of the LIE domain reduced palmitate-induced H3K27 acetylation and corresponding S100A11 upregulation in Huh7 cells and immortalized mouse hepatocytes. Silencing of the murine LIE in 2 independent steatohepatitis models demonstrated reduced S100a11 upregulation and attenuated liver injury. We confirmed H3K27 acetylation and XBP1s occupancy at the LIE domain in human MASH liver samples and an increase in hepatocyte-derived S100A11-enriched extracellular vesicles in MASH patient plasma. Our studies demonstrate a LIE domain that mediates hepatic S100A11 upregulation. This pathway may be a potential therapeutic target in MASH.

Abstract Background Physical activity is associated with lower colorectal cancer (CRC) risk, but its association with molecular subtypes defined by genetic and epigenetic alterations of the disease is unclear. Such information may enhance the understanding of the mechanisms related to the benefits of physical activity. Methods Pooled observational (cases: n = 5386; controls: n = 6798; studies n = 5) and genome-wide association data (cases: n = 8178; controls: n = 10 472; studies n = 5) were used. We used multivariable logistic regression models and Mendelian randomization to assess the association between physical activity and the risk of CRC subtypes defined by individual tumor markers (and marker combinations), namely microsatellite instability status, CpG island methylator phenotype status, and BRAF and KRAS mutations. We used case-only analysis to test for differences between molecular subtypes. We applied Bonferroni correction to account for multiple tests. Results In the pooled observational analysis, higher levels of physical activity were associated with lower CRC risk (Obs-per 1SD, odds ratio [OR] = 0.94, 95% confidence interval [CI] = 0.90 to 0.97), with an association that was stronger in males (Obs-per 1SD, OR = 0.91, 95% CI = 0.87 to 0.96) than in females (Obs-per 1SD, OR = 0.97, 95% CI = 0.91 to 1.03; Pinteraction = .04). Higher physical activity was associated with a lower risk of CRC across all molecular subtypes, especially in males. There was no difference in the associations by subtypes by pooled observational or Mendelian randomization analyses. The findings did not differ by study design, anatomical site, and early or late age onset of CRC. Conclusions Our findings suggest that physical activity is not differentially associated with the 4 major molecular subtypes involved in colorectal carcinogenesis, indicating that its benefits extend broadly across colorectal cancer pathogenesis.

In women with dense breasts, adding molecular breast imaging to digital breast tomosynthesis (DBT) increased both overall and invasive cancer detection rates, while modestly raising the recall rate compared with DBT alone.

Background: The COVID-19 pandemic brought profound changes to health care systems worldwide. This study examines the adaptive responses of a sleep medicine practice that successfully pivoted to telemedicine, remote diagnostics, and agile operations, resulting in sustained growth and improved patient accessibility. Methods: We analyzed organizational and cultural elements enabling responsiveness, including telemedicine infrastructure, adaptive leadership, quality-focused processes, and effective communication. Objective outcomes were assessed by analyzing patient demographics, telemedicine visits, and sleep testing patterns during three phases: pre-pandemic (June 1, 2018 to March 8, 2020), acute COVID-19 (March 9, 2020 to April 19, 2020), and post-acute COVID-19 (April 20, 2020 to December 31, 2021). Results: Across 105,199 encounters, monthly sleep medicine visits and testing declined ∼50% during acute COVID-19, but rebounded to surpass baseline in the post-acute phase. Virtual visits increased significantly, replacing many face-to-face encounters. Home sleep apnea test use rose sharply, driven by disposable WatchPAT tests, while polysomnography use decreased. Testing volumes increased overall post-acute compared with pre-pandemic. Patients served during acute and post-acute phases were younger, more often female, non-White, and postgraduate-educated (all p < 0.001). Nonlocal patients increased during the post-acute phase, reflecting telemedicine expansion. Conclusions: Proactive telemedicine investments, adaptive leadership, quality-focused processes, and effective communication enabled this practice to adapt successfully during the pandemic. These resilience strategies provide a model for navigating future health care challenges, underscoring telemedicine and e-health’s critical roles in maintaining care delivery during crises.

Abstract Background Lung adenocarcinoma in never-smokers is a major public health burden, especially among East Asian women. Polygenic risk scores (PRSs) are promising for risk stratification but are primarily developed in European-ancestry populations. We aimed to develop and validate single- and multi-ancestry PRSs for East Asian never-smokers to improve lung adenocarcinoma risk prediction. Methods PRSs were developed using genome-wide association study summary statistics from East Asian (8002 cases; 20 782 controls) and European (2058 cases; 5575 controls) populations. Single-ancestry models included a PRS with 25 single nucleotide variants (PRS-25), PRS clumping and thresholding (CT), and LDpred2; multi-ancestry models included LDpred2 plus European PRS-128, PRS-CSx, and clumping and thresholding, super learning, empirical Bayes (CT-SLEB). Performance was evaluated in independent East Asian data from the Female Lung Cancer Consortium and externally validated in the Nanjing Lung Cancer Cohort. We assessed predictive accuracy via area under the curve operating procedure (AUC), with 10-year and (ages 30-80 years) absolute risks estimates. Results The best multi-ancestry PRS, using East Asian and European data via CT-SLEB, outperformed the best East Asian-only (LDpred2; AUC = 0.629, 95% confidence interval [CI] = 0.618 to 0.641), achieving an AUC of 0.640 (95% CI = 0.629 to 0.653) and odds ratio of 1.71 (95% CI = 1.61 to 1.82) per standard deviation increase. Nanjing Lung Cancer Cohort validation confirmed robust performance (AUC = 0.649, 95% CI = 0.623 to 0.676). The top 20% PRS group had a 3.92-fold higher lung adenocarcinoma risk than the bottom 20%. Further, the top 5% PRS group reached a 6.69% lifetime absolute risk. Notably, this group reached the average population 10-year lung adenocarcinoma risk at age 50 years (0.42%) by age 41 years, 9 years earlier. Conclusions Multi-ancestry PRS approaches enhance lung adenocarcinoma risk stratification in East Asian never-smokers, with consistent external validation, suggesting future clinical utility.

ABSTRACTClinicians often repeat aquaporin‐4‐immunoglobulin G (AQP4‐IgG) testing in case of possible seroconversion. Compared with older, less sensitive immunofluorescence assays (IFA), cell‐based assays (CBA) offer higher sensitivity. This study assessed the frequency of seroconversion in a retrospective Cleveland Clinic cohort (2006–2024) of 451 patients with an initial negative AQP4‐IgG result who underwent serial testing. Seroconversion occurred in 4.3% (7/170) of patients initially tested by tissue IFA, but in none (0/263) of those tested by CBA. The lack of AQP4‐IgG seroconversion after a negative CBA, with only rare cases after a negative IFA, suggests that repeat AQP4‐IgG testing is low yield unless prior testing used older methods such as IFA.