Band 49, Heft 1

Platelet counting is a fundamental clinical test for diagnosing haemorrhagic diseases, coagulation abnormalities, and certain autoimmune disorders, and it also serves as a critical basis for decisions regarding platelet transfusion. Common automated methods for platelet counting include the international harmonization protocol (IHP) based on flow cytometry, CD61 immunoplatelet count (CD61-imm), impedance platelet count (PLT-I), hybrid platelet count (PLT-H), optical platelet count (PLT-O), and fluorescence platelet count (PLT-F). The IHP, based on flow cytometry, is recommended as the reference measurement procedure (RMP) by the Ministry of Health of the People’s Republic of China, the International Council for Standardization in Hematology (ICSH), and the International Society of Laboratory Hematology (ISLH) due to its superior precision and accuracy. Despite the significant improvements in efficiency and standardization brought about by automation, traditional blood smear microscopic examination (PLT-M) remains indispensable in specific scenarios, such as low platelet counts or abnormal platelet morphology, to ensure the accuracy and reliability of platelet counting results from automated methods.

Objectives This study systematically compared the performance and comparability of two medical laboratory analytical instruments, the conventional wet chemistry analyzer (cobas) and the dry slide technology (Vitros), across various clinical chemistry assays. Methods The evaluation focused on assessing imprecision, inaccuracy, recovery, and method comparison using leftover patient serum samples. Results The results indicated good to very good agreement for most clinical chemistry analytes, with larger differences observed for comparison of serum patient samples on albumin and protein. Conclusions Understanding and acknowledging method-specific variations, are crucial for accurate result interpretation in clinical laboratories. This study contributes valuable insights to ongoing discussions on method standardization.

Objectives Our study aimed to assess the stability of 26 biochemistry analytes in serum or plasma samples separated from blood samples centrifuged at different time intervals after collection, simulating sample transport via despatch delivery systems. Methods Blood from 41 volunteers was collected using five serum separator tubes (SST) and five fluoride oxalate tubes (FOT) for each volunteer following written informed consent. Each of the five tubes in both groups of SST and FOT was centrifuged at one of the time intervals: 0.5 h, 4 h, 8 h, 12 and 24 h after collection. These samples were left standing prior to centrifugation at room temperature. We calculated the percentage difference for each analyte between the 0.5 h and other time intervals to assess analyte stability. The percentage difference was compared to the desirable specification for bias and reference change value (RCV). Results Mean concentration of serum potassium showed a significant increase in the percentage RCV after 8 h, while CKMB showed an increase after 12 h of delayed centrifugation compared to the baseline (0.5 h). There were no significant percentage RCV for the other analytes at all timelines. Conclusions Serum potassium and CKMB were stable up to 8 and 12 h of delayed centrifugation respectively, whilst all other analytes appear stable up to 24 h, suggesting that sample transport delay of up to 8 h, with the condition that room temperature is maintained, may not have a significant impact on accuracy of the biochemistry/immunochemistry test results.

Objectives Aged patients are often characterized by difficult blood sampling conditions. Smaller needle gauge (G) may be beneficial for venous access and reduced pain perception, however, potentially at the expense of lower blood quality for laboratory measurements. We systematically compared two blood collection sets with different outer but equal inner diameters; different needle tips, and retract mechanisms in aged patients (Safety-Lok™, 23G, SL vs. UltraTouch™ Push Button, 25G, UT-PB) regarding clinical aspects and laboratory measurements. Methods Clinical examination and questionnaires were used in an aged cohort (n=161, average age=81.6 years), to determine characteristics of venipuncture, the phlebotomist’s assessment of blood draw including level of difficulty, and patient’s pain perception with either one or both blood collection sets. Sample quality was evaluated by laboratory analytics considering 13 parameters. Results SL, UT-PB, or both were used in 89 (55 %), 72 (45 %) or 36 (22 %) patients. The handling of the blood collection sets was perceived slightly easier for UT-PB compared to SL by the phlebotomist (−30 %, p=0.038). There was no significant difference in other parameters of the phlebotomist’s assessment or patients’ perception of blood collection. There was no clinically relevant difference between both sets in any of the laboratory measurements, including potassium and hemolysis index. Conclusions Clinical use of the UT-PB compared with SL in aged patients was associated with slight advantages of UT-PB, e.g. in the handling comfort for the phlebotomist. Sample quality, especially regarding hemolysis, was identical between both blood collecting sets, making its use uncritical in difficult venous conditions commonly seen in elderly patients.

Objectives Epstein-Barr virus (EBV) can cause lymphoproliferative disorders (PTLD) in immunodeficiency individuals. The pathogenesis of EBV infection depends on its effective recognition and elimination. Our study investigated the effect of peripheral lymphocyte subsets (PLS) on the elimination of EBV. Methods A retrospective single-center study included 63 patients with 17 pediatric liver transplant recipients with EBV-induced PTLD (PTLD group) and 46 patients diagnosed with EBV-induced mononucleosis (IM group). Dynamic monitoring of PLS with EBV-DNA loads was performed. Results EBV-DNA replicated at a high level (5.2E3∼5.93E7 copies/mL in PBMC) before treatment in all patients in PTLD group. B lymphocytes were the main infected cells. After treatment with Rituximab, the EBV-DNA loads decreased below the lower limit of detection in 10 patients (PTLD-stable disease, PTLD-SD group), and the viral loads replicated at lower level in six patients (PTLD-partial response, PTLD-PR group). In the PTLD-SD group, the percentage of CD3 + CD8 + T lymphocytes increased beyond the normal range with the ascending of EBV-DNA loads, then it decreased to the normal range accompanied by the clearance of EBV. In the PTLD-PR group, the CD3 + CD8 + T lymphocytes kept in the normal range, while the EBV kept on replication. Conclusions The increased number of CD3 + CD8 + T lymphocytes occurred in parallel with the decline in EBV-DNA loads, which is the most useful index in estimating the host capacity of immuno-surveillance against EBV.

Objectives The aim of this study is to investigate the correlation between preoperative serum glutathione reductase (GR) activity, alpha-fetoprotein (AFP) level, and early postoperative recurrence in patients diagnosed with hepatocellular carcinoma (HCC). Methods The data of 91 patients with HCC who underwent hepatectomy at Jinhua Hospital from January 2020 to December 2021 were retrospectively analyzed. A comparison of clinical characteristics between non-recurrent group and Recurrence group was conducted, and the association between GR activity, AFP levels, and early postoperative recurrence in HCC was investigated. Results Recurrence group (n=50) had a significantly higher AFP levels (median: 226.7 vs. 99.7 μg/L, p<0.001) and significantly lower GR activity (median: 55.0 vs. 68.0 U/L, p<0.0001) compared with non-recurrent group (n=41). The GR activity was negatively correlated with the AFP level (r=−0.4275, p<0.01). Low GR activity (OR=0.948; 95 % CI: 0.910–0.988; p=0.011) and high AFP levels (OR=1.003; 95 % CI: 1.000–1.006; p=0.036) independently contribute to an increased risk of early postoperative recurrence in HCC patients. The area under receiver operating characteristic curve of GR activity and AFP level for predicting early postoperative recurrence of HCC was 0.790 and 0.708, respectively. Patients with GR >60U/L had a higher early postoperative non-recurrence rate than patients with GR ≤60U/L (71.4 % [30/42] vs. 22.4 % [11/49]; HR=4.026; 95 % CI: 2.254–7.188; p<0.01); Patients with AFP ≤100 μg/L had a higher early postoperative non-recurrence rate than patients with AFP >100 μg/L (65.6 % [21/32] vs. 33.9 % [20/59]; HR=2.490; 95 % CI: 1.397–4.438; p<0.01). Conclusions The preoperative serum GR activity and AFP level hold significant predictive value for early postoperative recurrence in HCC patients.

Objectives The rapid detection of carbapenemase-producing bacteria is clinically important for selecting appropriate antimicrobial therapy. Recently, matrix-assisted laser desorption ionization time-of-flight mass spectrometry was used to detect carbapenemase activity. Methods In this study, we evaluated the detection power of MBT STAR-Carba test on identifying carbapenemase-producing bacteria isolated in Kobe city, Japan, compared with that of the KBM CIM Tris II kit using the modified procedure parameters. The obtained results were expressed as normalized logRQ values indicating a measure of hydrolysis efficiency. Results The MBT STAR-Carba test rapidly detected not only major carbapenemases, such as IMP-1 and IMP-6 that are most prevalent in Japan, but also GES-type and OXA-51-like carbapenemases, which are difficult to detect by reaction with inhibitors or KBM CIM Tris II by extending the incubation time. Conclusions The MBT STAR-Carba test will be beneficial in rapid identification of carbapenemases in clinical settings and environmental investigations.