Background Accurate coagulation testing is essential for clinical decision-making in emergency, surgical, and obstetric care. External quality assessment (EQA) is an important component of laboratory quality assurance; however, liquid or frozen EQA materials can impose logistical challenges related to temperature-controlled storage and transportation, particularly in low- and middle-income countries (LMICs). Lyophilized plasma may provide a practical alternative by improving material stability and reducing cold-chain dependence. Methods This study aimed to produce three batches of candidate lyophilized human plasma EQA materials representing three coagulation profiles (Levels 1–3) and to evaluate their quality according to ISO 13528:2022. Homogeneity was assessed using one-way analysis of variance, with 10 randomly selected vials per batch analyzed in duplicate on three automated coagulation analyzer platforms: Sysmex CS-2500, Stago Compact Max, and ACL TOP 350. The between-vial standard deviation (Ss) was compared with 0.3σpt. Refrigerated storage stability at 2–8 °C was evaluated over 5 months using the criterion |ȳt − ȳ0| ≤ 0.3σpt, while transport stability was assessed using an equivalence approach with the same acceptance limit. Results All three batches demonstrated acceptable homogeneity for prothrombin time (PT), activated partial thromboplastin time (APTT), and fibrinogen (Fib), with Ss ≤ 0.3σpt across the three analyzer platforms. The materials remained stable throughout 4 months of storage at 2–8 °C, and transport stability was demonstrated under ambient shipping conditions. Conclusion These findings indicate that the candidate lyophilized plasma materials possess satisfactory homogeneity, refrigerated storage stability, and transport stability, supporting their potential use as locally produced EQA materials for coagulation testing and reducing cold-chain dependence in resource-limited settings.
Antimicrobial-resistant (AMR) pathogens have emerged as a critical global health concern, necessitating the development of rapid and reliable screening tools. Conventional culture-based identification is labor-intensive and often delays appropriate antimicrobial therapy. This study aimed to develop and validate a multiplex polymerase chain reaction (PCR) assay for the simultaneous detection of methicillin-resistant Staphylococcus aureus, carbapenem-resistant Acinetobacter baumannii, and fluconazole-resistant Candida albicans. Initially, monoplex PCR was performed to evaluate the specificity and sensitivity of each primer set targeting 16S rRNA (bacterial identification), mecA (methicillin resistance), blaOXA-23 (carbapenem resistance), ITS (fungal identification), and MDR1 (azole resistance). Based on these results, multiplex PCR was developed to simultaneously detect multiple target pathogens within a single reaction. The assay successfully amplified all target genes, and no cross-reactivity was observed. Furthermore, multiplex PCR enabled the rapid, simultaneous detection of multiple AMR pathogens within a single reaction. A prototype multiplex PCR kit was also developed based on this study. Collectively, these findings indicate that the developed multiplex PCR assay has potential as a feasible approach for the simultaneous detection of AMR pathogens.
Objective To reveal the clinical diagnostic value of peripheral blood morphological examination by observing the morphological changes of peripheral blood in patients with type I and type II cryoglobulinemia. Methods This study included 11 patients from Peking Union Medical College Hospital who showed cryoglobulin crystal changes in peripheral blood morphology. Of these, 6 cases were diagnosed by electrophoresis as type I cryoglobulinemia and 5 as type II cryoglobulinemia, and their morphological changes were comprehensively summarized. Results Morphological examination of samples containing cryoglobulin crystals revealed the following findings: (1) In type I cryoglobulinemia, erythrocytes were observed encircling the cryoglobulin crystals, whereas in type II cryoglobulinemia, erythrocytes typically did not encircle the crystals unless cryoglobulin levels reached a specific threshold. (2) The morphology of the cryoglobulin crystals varied with time and temperature. (3) Under the microscope, cryoglobulin crystals in type I cryoglobulinemia appeared pale pink, whereas in type II cryoglobulinemia they were light gray and very faint, making them difficult to observe; imaging systems or automated scanners were therefore needed for better visualization. Conclusion Compared with normal blood smears, cryoglobulin crystals exhibited significant morphological changes. The use of wet blood smears, low-power lenses, and oil-immersion lenses can reveal diverse morphological features that may vary with time and temperature. Therefore, timely attention to peripheral blood morphological changes plays a crucial role in clinical laboratory testing.
Objective To analyze the biochemical characteristics of capillary blood-derived serum using Fourier-transform infrared (FTIR) spectroscopy, aiming to differentiate individuals diagnosed with Multiple Sclerosis (MS) from a matched control group (CG). Methods The study included 52 patients with confirmed MS and 52 healthy control participants, matched by sex and age. Serum samples were obtained via capillary blood collection and analyzed using mid-infrared ATR-FTIR spectroscopy. Chemometric analyses were performed on the full spectrum (3700–900 cm-1) and on the fingerprint (1800–900 cm-1) and high-wavenumber (3700–2800 cm-1) regions separately. Preprocessing included baseline correction and smoothing, followed by multivariate modeling using Partial Least Squares Discriminant Analysis (PLS-DA). Results FTIR spectroscopy combined with supervised machine learning revealed metabolic alterations between groups, including increased concentrations of phospholipids/lipids, nucleic acids, and Amide I/II in MS patients. The high-wavenumber region showed enhanced differentiation of control individuals, whereas the fingerprint region provided better separation between MS and CG. The combination of both spectral regions (full spectrum) yielded balanced performance metrics, sensitivity, specificity, and accuracy of 87.5%, highlighting their complementary diagnostic value. Conclusion FTIR spectroscopy of capillary blood serum provides distinct and complementary biochemical signatures for MS diagnosis. When integrated with machine learning algorithms, this approach demonstrated high discriminatory power. This is the first study to employ serum for capillary blood for FTIR-based MS classification, supporting its potential as a non-invasive, rapid, and accessible tool to assist in clinical decision-making.
