Although portal vein thrombosis (PVT) commonly occurs in patients with hepatocellular carcinoma (HCC), the hypercoagulability mechanism in patients with HCC is not entirely clear. Recently, tumor-induced formation of neutrophil extracellular traps (NET) has been shown to trigger contact system activation, and contact system activation has been shown to be a new mechanism of thrombosis. Therefore, we investigated whether contact system activation and NET formation occurred in relation to PVT in HCC patients. The circulating levels of NET formation markers (DNA–histone complex, double-stranded DNA, neutrophil elastase) and contact system activation markers (factor XIIa and high-molecular-weight kininogen) were measured in 177 patients who had been diagnosed with HCC and 48 healthy controls. Presence of PVT was confirmed in 77 HCC patients. The levels of NET formation and contact system activation markers were significantly higher in patients than in healthy controls and they increased significantly with the increase in the model for end-stage liver disease (MELD) scores. Of note, these markers were significantly higher in HCC patients with PVT than in those without PVT. These NET formation markers and the contact system activation markers were significant thrombotic risk factors in HCC patients. The well-known liver injury markers (alanine transaminase, prothrombin time) significantly contributed to factor XIIa level. Contact system activation and NET formation are well correlated with liver disease severity and the markers of these can be used as thrombotic risk factors in HCC patients. In addition, therapeutics inhibiting the contact system can be potentially used to manage PVT in HCC patients.

Ji Yeon Sung, M.D., Jong Do Seo, M.D., Dae-Hyun Ko, M.D., Min-Jeong Park, M.D., Sang Mee Hwang, M.D., Sohee Oh, Ph.D., Sail Chun, M.D., Moon-Woo Seong, M.D., Junghan Song, M.D., Sang Hoon Song, M.D., and Sung Sup Park, M.D.. Ann Lab Med 2021;41:155-70. https://doi.org/10.3343/alm.2021.41.2.155

Vitamin D (vit-D) deficiency is highly prevalent in the Korean population, highlighting the need for accurate measurements. In this study, the interferences by endogenous and cross-reactive substances were compared between routine vit-D immunoassays and mass spectrometry (MS) methods. Two MS methods and 4 immunoassays from different manufacturers (Abbott, Beckman Coulter, Roche, Siemens) were compared. Residual samples that were icteric, lipemic, hemolyzed, high in rheumatoid factor, from myeloma patients, or patients undergoing hemodialysis were collected. Also, 4 levels of National Institute of Standards and Technology (NIST) Standard Reference Material 972a, and 12 samples serially spiked with 3-epi-25-OH-D₃ were prepared. Significant interferences were observed in hemolytic (Roche), icteric (Beckman and Siemens) and lipemic samples (all 4 immunoassays). Level 4 NIST material and 3-epi-25-OH-D₃-spiked samples induced significant cross-reactivity, yielding higher total vit-D measurements in non-epimer-separating MS methods, and both the Beckman and Roche immunoassays. Most observed interferences were consistent with manufacturers’ claims, but overall improvement of immunoassay bias limits is required. Awareness of potential interference is important to increase the accuracy of vit-D measurements. Moreover, care is due when interpreting vit-D results of newborns, infants and less commonly, pregnant women, who are known to have physiologically high levels of the highly cross-reactive 3-epi-25-OH-D₃.

Background: The type of blood collection tube affects specimen quality and laboratory results. Because plasma specimens have a shorter processing time compared with serum specimens, emergency biochemistry tests use plasma. However, serum specimens remain stable after centrifugation and show more accurate results than plasma. Therefore, a quick-clotting serum separator tube is expected to be useful for shorter turnaround times and accurate results. We evaluated a new quick-clotting serum separator tube VQ-Tube™ (AB Medical, Korea) for clinical chemistry and thyroid hormone assays. Methods: One hundred volunteers from four university hospitals were recruited, and peripheral blood samples were collected in quick-clotting serum separator tube VQ-Tubes™ and the commonly used serum separator tube V-Tubes™. The obtained specimens were used for 16 clinical chemistry assays and three thyroid hormone assays. Results: The differences (%) in the test results obtained from the samples in each tube satisfied the allowable difference ranges (19 assays). The differences in the test results between the tubes satisfied the desired specifications for accuracy except for the glucose results (2.75%). The paired t-test revealed significant differences between the results of six assays, but each set of results showed a good correlation. Samples were visually inspected for serum clarity and gel barrier integrity, and incomplete clotting reactions and haemolysed serum were not observed. Conclusions: The new quick-clotting VQ-Tube™ demonstrated reliable test results compared with the commonly used serum separator tube V-Tube™. This quick-clotting tube will provide fast test results with adequately separated serum specimens, especially for patients who need fast tests.

Jong Do Seo, M.D., Gye Cheol Kwon, M.D., Jeong-Ho Kim, M.D., Sang-Guk Lee, M.D., Junghan Song, M.D., Pil-Whan Park, M.D., Dongheui An, M.D., Qute Choi, M.D., Chan-Ik Cho, M.P.H., Sollip Kim, M.D., and Yeo-Min Yun, M.D.. Ann Lab Med -0001;0:. https://doi.org/10.3343/alm.2025.0010

Background: Hemoglobin A_1c (HbA_1c) is arguably the most important biomarker used in the diagnosis and treatment monitoring of diabetes mellitus. We evaluated the analytical performance of the Norudia HbA_1c assay (Sekisui Medical Co., LTD), which uses an enzymatic method incorporated into a fully automated, high‐throughput system.Methods: The precision, linearity, and carryover of the Norudia HbA_1c assay were evaluated. Using 60 patient samples, comparative analysis of HbA_1c measurements with two commonly used HbA_1c assays, the D100 (Bio‐Rad Laboratories, Inc) and HLC‐723 G11 (Tosoh), was undergone. Thirteen commutable samples with known HbA_1c concentrations measured using an IFCC reference measurement procedure were used to compare accuracy between methods. Interference of HbA_1c measurement by Hb variants was evaluated using 16 known Hb variant samples.Results: Repeatability (% CV) for low and high concentrations ranged from 1.12%‐1.50% and 0.66%‐0.75%, respectively, and within‐laboratory precision for low and high concentrations ranged from 1.73%‐2.89% and 0.98%‐1.64%, respectively. For linearity, the coefficient of determination was 0.9987. No significant carryover was observed. When compared to the D100 and HLC‐723 G11 assays, the Norudia HbA_1c assay showed the best accuracy with the lowest mean bias (−1.72%). Furthermore, the Norudia was least affected by Hb variants and gave the most reliable HbA_1c measurements.Conclusion: The Norudia HbA_1c showed excellent analytical performance with good precision and linearity, and minimal carryover. When compared to other routine HbA_1c methods, the Norudia HbA_1c assay showed the highest accuracy and was least affected by Hb variants.