International journal of laboratory hematology最新文献

Introduction: Hematopoietic stem cell transplantation (HCST) is a widely used therapy in the management of hematological malignancies, leading to cytopenias that require transient transfusions. Platelet recovery (PR) following HSCT is assessed by monitoring platelet count (PC). Immature platelet fraction (IPF) is a research parameter offered by Sysmex® on XN series analyzers, enabling rapid diagnostic orientation in the event of thrombocytopenia. It has also been described as a predictive factor for PR after chemotherapy or HSCT, and thresholds have been proposed.

Methods: The objective of this study was to assess the predictive capability of IPF for PR in a prospective cohort of patients undergoing HSCT and to evaluate its utility in guiding platelet transfusion decision.

Results: An optimized A-IPF (absolute number of IPF) threshold of 2.5 × 10⁹/L was predictive of a PC greater than 50 × 10⁹/L at day 30 with a sensitivity of 78.9%, specificity of 78.6%, positive predictive value (PPV) of 83.3% and negative predictive value (NPV) of 73.3%. We were able to distinguish patients recovering PC before day 15 with an earlier %IPF peak, greater IPF recovery kinetics and faster neutrophil recovery.

Conclusion: A-IPF shows promise as a predictor of PR following HSCT. A multicenter study could help confirm both A-IPF and %IPF (IPF) clinical utility before it is made available to clinicians.

Objectives: Immature platelet fraction (IPF) for differentiating bacteremia has been explored, whereas its prognostic correlation remains uncertain. This study aims to confirm the predictive capability of IPF for bacteremia and investigate its association with prognosis.

Methods: Patients with complete blood count (CBC) on the blood culture day (D1) and the preceding day (D0) were retrospectively recruited and categorized into bacteremia and nonbacteremia groups. Immature platelet (IP) analysis, alongside CBC, was conducted. Delta IPF, defined by the absolute values of D1 minus D0 results was calculated. The ability to distinguish bacteremia from nonbacteremia patients, and the correlation with mortality were analyzed.

Results: From February to December 2020, a total of 150 patients were enrolled, with 75 having bacteremia. The specificity for delta IPF ≥3.4% to predict bacteremia was 97.3% (95% confidence interval [CI]: 90.7-99.7). When delta IPF ≥3.4% combined with procalcitonin ≥0.5 (ng/mL), the sensitivity was 90.5% (95% CI: 69.6%-98.8%). Within the bacteremia group, delta IPF and the proportion of patients with delta IPF ≥1.5% were significantly higher in nonsurvival, while delta platelet levels did not. Furthermore, delta IPF ≥1.5% was independently associated with 30-day mortality (adjusted odds ratio: 3.88, 95% CI: 1.2%-11.4%; p = 0.020). The 30-day survival curve demonstrated a significant difference between patients with delta IPF ≥1.5% and those without (p < 0.001).

Conclusions: Delta IPF correlates with mortality in bacteremia patients. Our findings suggest IPF not only helps detect bacteremia but also predicts prognosis in the early stage.

Introduction: We aimed to develop an automated, low-volume method for thrombocyte counting in capillary blood using the Sysmex predilution (PD) mode.

Methods: Microsamples were prepared by resuspension of 50 μL blood in 300 μL DCL CellPack. Thrombocyte counting was done in the impedance (PLT-I) and fluorescence (PLT-F) channels. The imprecision and bias was evaluated in >394 microsamples from adult blood. Preanalytical factors (skin-piercing, storage, and transportation in our pneumatic tube system) was assessed, and studies on pediatric microsamples were made for comparison. The improvement in analytical quality and turnaround time was examined.

Results: For PLT-F, the imprecision was 1.1%-3.7%, and the bias was 10.1% (95% CI: 8.8-11.3). After skin-piercing, the bias was 8.1% (95% CI: 5.6-10.6) and the imprecision 1.9% (95% CI: 1.3-2.5). Thrombocyte counts kept stable after 4 h at room temperature (94.8% [95% CI: 93.2-96.4]) and after pneumatic tube transportation [6.7% (95% CI: 4.8-8.6)]. The bias of the PD mode for pediatric microsamples was 13.0% (95% CI: -8.4-34.4) in the PLT-F channel. The automated method had a considerably lower imprecision than the existing manual thrombocyte counting method and reduced turnaround times.

Conclusion: The automated microsample method offers a low-volume alternative for measurement of thrombocytes. The method appears useful also in pediatric samples.