Laboratory medicine最新文献

Introduction: A questionnaire was sent to immunology laboratories worldwide by the European Organisation for External Quality Assurance Providers in Laboratory Medicine to evaluate current practice with regard to how antinuclear antibodies (ANAs) are routinely tested in clinical laboratories.

Methods: In total, 494 questionnaires were returned from 44 countries. Of these, 379 provided sufficient information to be included in the analysis.

Results: Indirect immunofluorescence on HEp-2 cells is still the most common method to test ANAs and is used by 330 of our 379 respondents. The most common (60%) screening dilution is 1:80, followed by 1:160 (15%) and, in equal amounts, 1:40 and 1:100 (8% each). In most laboratories, ANA-positive samples are further diluted to an end titer of 1:1280 (40%), 1:2560 (21%), 1:5120 (16%), or 1:640 (19%). An increasing number of laboratories (178/330) use the International Consensus on ANA Patterns (ICAP) nomenclature to describe the immunofluorescence pattern on HEp-2 cells. In countries with the most respondents, the percentage of laboratories accredited to EN International Organization for Standardization (ISO) 15189 (in Britain, BS EN ISO 15189, which is a British standard as well as a European standard as well as an ISO standard with identical content) is between 8% (Belgium) and 60% (France). There was no difference in the portion of accredited laboratories between university hospitals, nonuniversity hospitals, and private laboratories.

Discussion: Indirect immunofluorescence continues to be the most frequently used technique for ANA testing in laboratories. The increasing number of laboratories using the ICAP classification reflects an ongoing harmonization of describing ANA patterns on HEp-2 cell substrates.

Introduction: Duchenne muscular dystrophy (DMD) is a severe genetic disorder affecting 5% to 19% of carriers. Creatine kinase (CK) is a traditional biomarker for DMD, but its screening accuracy is limited. This study evaluated the potential of combining the proto-oncogene tyrosine-protein kinase receptor Ret (RET) with CK-MM to enhance screening efficacy.

Methods: Creatine kinase-MM and RET levels were analyzed in 14 adult and 5 newborn carriers of DMD, along with noncarrier control individuals. The CK-MM/RET ratio was calculated, and a receiver operating characteristic curve analysis evaluated biomarker screening efficiency. Methods for extracting RET from dried blood spots (DBSs) were compared with correlations between DBSs and serum RET levels and stability under varying storage conditions.

Results: Carriers of DMD exhibited elevated CK-MM and CK-MM/RET ratios with reduced RET. The CK-MM/RET ratio had the highest screening efficiency. Extraction of RET was optimal using Diluent C at 4 °C overnight, showing a strong DBS-serum correlation; RET remained stable, except under high humidity and temperature conditions.

Discussion: Combining RET with CK-MM enhances DMD carrier screening, offering a more efficient DBS-based method for early detection.

Introduction: Cold-reacting antibodies that bind to and trigger premature erythrocyte destruction are present in patients with cold autoimmune hemolytic anemia (cAIHA). The diagnosis of cAIHA is challenging because of the rarity of the disease, especially in patients with nonspecific features.

Methods: In this case report, we discuss an unusual case of cAIHA in an older man who presented with asymptomatic hyperkalemia, highlighting the hematologic and biochemical changes associated with the disease.

Results: Although hyperkalemia is expected with in vivo hemolysis because of autoantibody-mediated destruction of red blood cells, pseudohyperkalemia caused by in vitro hemolysis was also detected. The combination of actual in vivo hyperkalemia and pseudohyperkalemia resulted in a measured potassium value that was higher than the in vivo potassium concentration.

Discussion: It is pertinent to consider both in vivo and in vitro hemolysis in patients with cAIHA, particularly when assessing potassium status, so that an appropriate intervention can be administered for better patient outcomes.

Introduction: About one-third of multiple myelomas produce excess free monoclonal light chains. Detection of monoclonal light chains is important for diagnosis, prognosis, and monitoring of such lesions. A previously described method for detection of monoclonal light chains in serum required multiple manual wash steps. Even though the method has sensitivity similar to that of mass spectrometry, the manual wash steps were a hindrance to the method's widespread use.

Methods: To mitigate the laborious nature of the previous method, the SPIFE Nexus instrument (Helena Laboratories) was modified to automate the sample application, electrophoretic separation, antibody application, washing and blotting steps needed for removal of background proteins. Background noise was mitigated by modifying the wash buffer by adding a detergent. This revised automated electrophoresis protocol was tested in parallel with the previously described method.

Results: The sensitivity and specificity of the modified method using antisera to free light chains from 2 sources was comparable to the parameters of the previously described method without the need for manual manipulation.

Discussion: The automated protocol employing the SPIFE Nexus instrument and incorporating antisera to free light chains is suitable for routine use in clinical laboratories in an automated, enhanced-sensitivity assay for monoclonal light chains with no need for manual manipulation.

This case report describes a patient with a medical history of schizophrenia, found in a coma with hyperthermia, likely due to classic heatstroke. The white blood cells observed on the blood smear showed cytological abnormalities characterized by multilobed nuclei, which could be early signs of cell death. The evolution into multiorgan failure led rapidly to death.

Introduction: We sought to compare clinical features among distinct antibody profiles defined by the presence or absence of antinucleosome (anti-NCS) and anti-double-stranded DNA (anti-dsDNA) antibodies in Tunisian patients with systemic lupus erythematosus (SLE).

Methods: The study enrolled 131 patients with SLE meeting at least 4 American College of Rheumatology or SLICC criteria. Participants were recruited from the Department of Internal Medicine and Rheumatology at the university teaching hospital of Monastir between January 2000 and December 2022. The patients were divided into 4 groups: Group 1 with neither anti-dsDNA nor anti-NCS; Group 2 with anti-dsDNA and no anti-NCS; Group 3 with anti-NCS lacking anti-dsDNA; and Group 4 with both anti-NCS and anti-dsDNA.

Results: The mean (SD) age at the time of diagnosis for the 131 participants with SLE was 38.7 (15.1) years; the ratio of female to male individuals was 7.2. Thirty-four (26%) patients were positive for anti-NCS and anti-dsDNA (group 4: antinuclear antibody pattern AC-1, 72%; pattern AC-5, 16%), and 30 (22.9%) were positive for anti-NCS and negative for anti-dsDNA (group3: pattern AC-1, 53.6%; pattern AC-5, 32.1%). The group 3 patients showed higher peripheral neuropsychiatric SLE (P =.034) and lower rates of disease activity (P =.01). The comparison between the 4 groups showed that group 4 patients had the highest frequency of lupus nephritis (P ≤.001) and the highest rate disease activity (P =.013).

Discussion: Patients with both anti-NCS and anti-dsDNA at the time of diagnosis are likely to have severe SLE, while anti-NCS was associated with nonsevere disease in patients with SLE who lack anti-dsDNA.

Introduction: Blood transfusions are routinely performed in operation rooms. The process chain of performing ABO type, antibody screen, crossmatch, blood transport, and patient verification is complex. A multidisciplinary task force convened to improve the process of blood ordering and utilization identified 3 issues: (1) blood orders performed on paper included transcription errors; (2) guidelines for blood ordering practices were lacking, with inappropriate and arbitrary requests; and (3) there were long intervals between ordering and receiving blood in the operating room because of its distance from the blood bank.

Methods: The task force implemented (1) an electronic positive patient identification (ePPID) system, (2) a standardized computer provider order entry (CPOE) for ordering blood for surgical patients, and (3) an electronic remote blood issuing (ERBI) system using refrigerators located within the operating suite.

Results: Following ePPID implementation, transfusion documentation compliance rates improved from 71% to 98% and detected 2 patient safety issues. Implementation of CPOE with a maximum surgical blood order schedule and ERBI led to a substantial decline in blood product dispensed from coolers and reduced returns of unused red blood cells (from 30% to 15%) and plasma units (from 45% to 30%) to the blood bank over 2 years.

Discussion: Electronic PPID, CPOE, and ERBI improved patient safety, workflow, and efficiency during blood transfusions.

Introduction: The Clinical Laboratory Improvement Amendments require nonconforming safety event identification, targeted intervention, and evaluation of interventional effectiveness. Without a standardized reporting structure, risk and safety teams will experience ongoing challenges with situational awareness and mitigation strategies in the workplace.

Methods: A 15-minute risk and safety huddle was initiated. The cadence was set to daily for the first iteration of huddle integration. A subsequent cadence was set to twice weekly, with a Microsoft Teams channel for streamlined communication across all laboratory settings.

Results: Huddling resulted in an averaged time savings of 14 days (approximately 2 weeks), measured from event to safety report. An observed reduction of 17.6% in employee-reported occupational safety events was noted between quarters 1 and 2 of 2023 and between quarters 1 and 2 of 2024, with a reduction in overall event spending ($458.50 [19.2%]) noted in 4 of the 5 measured safety event categories. An annual reduction in spending ($9568.09 [49.8%]) across all 5 measured safety event categories was noted in the 2022 (preinterventional) and 2023 (postinterventional) time frame.

Discussion: Laboratories should consider the establishment of a dedicated safety committee and cadenced huddles because such tools are effective for improving safety and communicating occupational hazards.

Introduction: Discrepancies in gel card immunohematologic testing can result in false-positive reactions, making detecting antibodies and performing crossmatching difficult. Such unexpected reactivity may result from interactions with test system components, including the column matrix, chemicals, or reagents, rather than true antigen-antibody binding. Accurate identification and resolution of these discrepancies are crucial to prevent delays in transfusion and ensure patient safety.

Methods: This case involved a 24-year-old patient with sickle cell disease who required a blood transfusion, highlighting the diagnostic challenges posed by variability in gel card platforms. Blood grouping was performed using Tulip gel cards (Tulip Diagnostics, Pvt Ltd).

Results: The forward grouping was AB positive, but the reverse grouping showed pan-positive results. Repeat grouping by the gold standard-the conventional tube technique-resolved the discrepancy, and the blood group was identified as AB positive. Antibody screening (ABS) and autoantibody testing using Tulip gel cards showed pan-positive reactions, although the direct antiglobulin test was negative. However, conventional tube techniques for ABS and thermal amplitude tests for autoantibodies were negative. Crossmatching of phenotype-matched packed red blood cell units showed incompatibility on Tulip gel cards but compatibility using the conventional tube technique. The possibility of antibodies against enhancement media, such as low-ionic-strength solution, was ruled out after repeat testing with normal saline and phosphate-buffered saline, which showed negative reactions in different immunohematology tests. Due to suspected interference from the gel card components, crossmatching, ABS, and autoantibody testing were repeated using Bio-Rad gel cards, which showed compatible results.

Discussion: The false-positive reactions were attributed to antibodies against materials in Tulip gel cards, including silica-based microbeads, polyvinyl alcohol, and other stabilizers that are absent in Bio-Rad gel cards. This case underscores the importance of multiplatform validation, reagent standardization, and conventional tube testing in resolving immunohematologic discrepancies and ensuring safe transfusion practices.

Introduction: Human epididymis protein 4 (HE4), a potential novel biomarker for cancers, has been widely used in clinical practice, but evidence of its prognostic value for non-small cell lung cancer (NSCLC) remain insufficient. This study aimed to explore the predictive value of serum HE4 levels on detecting recurrence or metastasis and cancer death among patients with NSCLC.

Methods: We included 102 cases of confirmed NSCLC and 99 healthy control individuals in our cohort study. Venous blood samples from these fasting participants were extracted upon admission for testing serum HE4 levels. Cox regression analysis was used to evaluate the risk of end point events (recurrence or metastasis and cancer death) during a 3-year follow-up.

Results: Among the patients with NSCLC, Kaplan-Meier analysis showed that individuals with median serum HE4 levels of 177.84 pmol/L or higher had much higher risk of recurrence or metastasis and cancer death than did individuals with median serum HE4 levels below 177.84 pmol/L (P < .005). An adjusted model by Cox regression analysis suggested strong associations between serum HE4 levels and recurrence or metastasis (hazard ratio, 2.9 [95% CI, 1.8-6.2], P < .01) and cancer death (hazard ratio, 3.8 [95% CI, 2.5-7.9], P < .01) after confounding variables, including age, sex, smoking history, drinking history and treatment methods, were adjusted for. Furthermore, receiver operating characteristic curve analysis showed that the diagnostic model combining 4 biomarkers-HE4, carcinoembryonic antigen, cytokeratin 19 fragment antigen, and squamous cell carcinoma antigen-exhibited the largest area under the curve (0.996) for diagnosing composite events, with 96.2 % sensitivity and 98.4% specificity.

Discussion: There was an independent correlation between high serum HE4 levels at admission and an increased risk of recurrence or metastasis and cancer death from NSCLC that supports serum HE4 as a biomarker for survival prognosis after NSCLC treatment.