Clinical laboratory最新文献

Background: Early diagnosis of Mycobacterium tuberculosis (MTB) infection is of great significance for the clinical management of tuberculosis (TB). We first explored the efficacy of single-molecule nanopore DNA sequencing in the early diagnosis of suspected TB patients and analyzed the advantages in differentiating and diagnosing MTB and non-tuberculous Mycobacteria (NTM).

Methods: In this cohort study, we reviewed the clinical data of suspected TB patients admitted from December 1, 2021, through April 15, 2022. All patients underwent 3 - 6 times acid-fast bacilli smear examinations of sputum, all of which were negative. To make a definitive diagnosis, we extracted specimens from the patients and performed specimen culture, Xpert MTB/Rif assay, and single-molecule nanopore DNA sequencing. The efficacy of different diagnostic methods in diagnosing suspected TB patients was compared using "Diagnostic Criteria for Pulmonary Tuberculosis" (WS288-2017) as the gold standard.

Results: Among the 25 patients, 15 were infected with MTB, 5 were infected with NTM, 1 had mixed MTB and NTM infection, and 4 were negative. The accuracy of single-molecule nanopore DNA sequencing in diagnosing mycobacterial infection (MTB + NTM) was 92.0%, with a sensitivity of 90.5% and a specificity of 100%; the accuracy of diagnosing MTB infection was also 92.0%, with a sensitivity of 87.5% and a specificity of 100%. Single-molecule nanopore DNA sequencing showed an accuracy of 100% in differentiating MTB and NTM. However, the diagnostic accuracy and sensitivity of specimen culture and Xpert MTB/Rif assay were relatively low (≤ 52%) compared to "specimen culture + Xpert MTB/Rif assay". The diagnostic efficacy of single-molecule nanopore DNA sequencing was not affected by the source of tissue samples, while specimen culture and Xpert MTB/Rif assay could not diagnose mycobacterial infection using extrapulmonary specimens.

Conclusions: As a third-generation sequencing technology, single-molecule nanopore DNA sequencing has significant application value in diagnosing suspected TB patients. Compared to traditional diagnostic methods, such as specimen culture and Xpert MTB/Rif assay, single-molecule nanopore DNA sequencing exhibits high diagnostic efficacy, low error rate, and convenient detection.

Background: Serum human chorionic gonadotropin (HCG) is a glycoprotein hormone secreted by the trophoblast cells of the placenta. HCG levels are helpful in confirming and monitoring pregnancy, as well as in the diagnosis and monitoring of trophoblastic tumors. Therefore, the accuracy of HCG detection results is of great significance for the diagnosis and differential diagnosis of pregnancy and germ cell tumors.

Methods: We report a case of pseudo elevation of serum HCG in a patient with rheumatoid arthritis. The possibility of abnormal increase in HCG concentration caused by rheumatoid factor (RF) was evaluated using polyethylene glycol (PEG) precipitation method and different detection platforms.

Results: Samples pretreated with polyethylene glycol and samples using another detection platform showed a significant decrease in serum HCG concentration and a negative reaction. Therefore, the patient's HCG result showed an abnormal increase, which is considered a false increase caused by RF interference.

Conclusions: When serum HCG levels are abnormally elevated in patients with rheumatoid arthritis but there is no evidence of pregnancy or clinical symptoms related to trophoblastic tumors, staff should consider the possibility of RF interference in HCG detection, take corresponding corrective measures, and communicate with clinical doctors in a timely manner.

Background: Chronic NK-cell lymphoproliferative disease (CLPD-NK) is a very rare lymphoproliferative disorder in which patients often have an elevated lymphocyte population without clinical symptoms.

Methods: In this particular case, a middle-aged woman presented with a consistent elevation in her lymphocyte proportion over a span of four consecutive years during physical examinations, without manifesting any other notable clinical symptoms. The underlying cause of this phenomenon was ultimately identified through a comprehensive evaluation that encompassed peripheral blood cell morphology analysis, lymphocyte subset profiling, and peripheral blood immunophenotyping. These diagnostic tools collectively provided crucial insights into the nature of the disease.

Results: The patient was finally diagnosed with CLPD-NK. As part of her management plan, the patient was advised to undergo regular annual physical examinations to monitor the progression of the disease and any potential changes in her health status.

Conclusions: CLPD-NK is a chronic progressive lymphoproliferative disease, which can be followed up regularly if there are no clinical symptoms. Severe reductions in neutrophils, red blood cells, and platelets or other complications may require chemotherapy or bone marrow transplantation.

Background: Chronic subdural hematoma (CSDH) is a type of spontaneous or post-traumatic intracranial hemorrhage located between the dura mater and arachnoid membrane. It is a neurosurgical disease that often occurs in the elderly. Burr-hole drainage is the main treatment method, and smear microscopic examination of the drainage fluid is a common laboratory method.

Methods: A cranial magnetic resonance imaging (MRI) was performed, then blood and drainage fluid from patients with CSDH was collected and sent to the laboratory for routine laboratory tests.

Results: Both patients' cranial MRI indicated CSDH, while no significant abnormalities were found in blood-related tests. Microscopic examination of postoperative drainage fluid revealed a significantly increased proportion of eosinophils.

Conclusions: It is found that the mechanism of eosinophil infiltration in CSDH and its significance for patients are still unclear by combining the cases and relevant literatures. Further research is needed to study the distribution and changes of eosinophils and related chemokines in the peripheral blood and postoperative drainage fluid from CSDH patients, which is of great significance for the treatment and recurrence prediction of CSDH patients.

Background: Early confirmation of infections with influenza virus and/or respiratory syncytial virus (RSV) is beneficial for prompt treatment and outbreak management. This study aimed to assess the Cepheid Xpert Xpress Flu/ RSV assay in Central China, using Sanger sequencing as the reference method.

Methods: Nasopharyngeal swab (NP) samples from pediatric and adult patients with influenza-like illnesses were collected by the Hubei Province Disease Control and Prevention Center. The Xpert Xpress Flu/RSV assay was performed according to the manufacturer's guidelines, and the cycle threshold (Ct) values of each positive sample were recorded. Sanger sequencing was then performed on the NP samples, and discordant results were verified with a self-built fluorescent PCR method and virus tissue culture.

Results: The Xpert assay demonstrated a sensitivity of 97.06%, a specificity of 95.81%, an accuracy of 95.93%, a PPV of 71.74%, and a negative predictive value (NPV) of 99.66% for influenza A (Flu A) detection. Influenza B (Flu B) detection had a sensitivity of 100%, a specificity of 88.52%, an accuracy of 91.86%, a PPV of 78.12%, and an NPV of 100%. RSV detection had a sensitivity of 100%, a specificity of 95.67%, an accuracy of 98.80%, a PPV of 60.00%, and an NPV of 100%. False positive samples had significantly higher mean Ct values compared to true positive samples for detecting Flu A, Flu B, or RSV (p < 0.001).

Conclusions: The Xpert Xpress Flu/RSV test is a rapid, accurate, and reliable molecular diagnostic method for Flu A, Flu B, and RSV. Positive Xpert results with a low Ct value are more likely to indicate a clinical infection with Flu/RSV to allow timely diagnosis and treatment.

Background: Hepatitis B virus (HBV) infection is one of the most common health problems worldwide and is associated with high mortality and heavy economic burdens. The aim of this study was to determine the prevalence of hepatitis B surface antigen (HBsAg) and associated risk factors among pregnant women attending antenatal clinics at Adigrat General Hospital in Northern Ethiopia.

Methods: An institutional-based cross-sectional study was conducted from January to March 2024 among 385 pregnant women. Participants were selected through a systematic random sampling method. Socio-demographic and associated factor data were collected using a structured questionnaire, and 5 mL blood samples were collected. The data were subsequently entered into EPI Info and analyzed using SPSS version 25. Descriptive statistics were computed. Bivariate and multivariate regression analyses were employed to measure associations, and values < 0.05 were considered to indicate statistical significance.

Results: The overall seroprevalence of HBsAg among the 385 study subjects enrolled was 10.4% (n = 40). HBsAg was common in all age groups. The prevalence of infection was greater in those who had a history of multiple sexual partners (22.7%), early piercing (13.4%), or abortion (27.6%), as was the history of delivery (26.3%) and genital mutilation (35.7%). According to multivariate logistic regression, patients were unmarried (AOR 8.57; 95% CI 3.20 - 22.93), illiterate (AOR 12.06; 95% CI 3.07 - 47.33), had a history of ear piercing (AOR 5.66; 95% CI 1.65 - 19.45), a history of abortion (AOR 8.16; 95% CI 3.18 - 20.95), a history of home delivery (AOR 6.69; 95% CI 1.26 - 35.53), and a history of genital mutilation (AOR 9.77; 95% CI 2.64 - 36.18) for acquiring HBV infection compared to their counterparts.

Conclusions: The results showed that HBV was highly prevalent in our study area. Being unmarried, having a low educational level, having an ear piercing, having an abortion, having a home delivery, and having genital mutilation were significantly associated with HBV infection. Therefore, these findings suggest that health education programs should be provided to the community to increase awareness among mothers.

Background: Acquired coagulation factor deficiency is an autoimmune hemorrhagic disease caused by the production of antibodies to coagulation factor. The incidence of acquired coagulation factor XI deficiency is low and rarely reported.

Case presentation: We report a case of a patient with acquired coagulation factor XI deficiency. The patient was a 24-year-old female who presented with mild yellowing of the skin, general malaise, palpitation, and no obvious bleeding symptoms prior to admission, such as skin and mucous membrane petechiae. She was initially diagnosed with anemia because her hemoglobin was 62 g/L. Laboratory results showed activated partial thromboplastin time (APTT) prolonged with a test value of 83.40 seconds and could not be corrected by corrective experiments; Factor XI activity was less than 0.1%, positive for factor XI antibody, and a plasma coagulation factor XI inhibitor was 35.20 BU/mL. She was eventually diagnosed with acquired coagulation factor XI deficiency, Plasmapheresis were performed to clear antibodies, and patient's condition improved.

Conclusions: Plasmapheresis played a positive role in the treatment of acquired factor XI deficiency. Clear early diagnosis and proper treatment can help to improve the cure rate of patients.

Background: The incidence of monoclonal gammopathy of undetermined significance (MGUS) in the population of over 50-year-olds is approximately 3% and increases with age. The association between MG and neuropathy has been of interest for several years, but the causal relationship has not yet been clarified.

Methods: For 682 patients who visited the Department of Neurology and requested tests for MG work-up, we retrospectively collected demographic and clinical information, such as age, gender, diagnosis, and neurologic and laboratory test results, from their medical records.

Results: Out of a total of 682 patients who were suspected of neuropathy and tested for monoclonal gammopathy (MG), twelve (1.76%) showed MG on their serum protein electrophoresis. The most common form was IgM-κ with five patients, followed by IgG-κ, IgG-λ, and biclonal IgG-λ and IgA-κ. The results of the immunoglobulin quantitation test and free light chain assay showed that involved M-protein values in these patients were increased. Some patients were positive for anti-myelin-associated glycoprotein (MAG) antibody, anti-GD1b IgM antibody, anti-GM1 IgG & IgM antibody, and anti-cardiolipin IgM antibody. Also, some had antinuclear antibody (ANA) or antineutrophil cytoplasmic antibody (ANCA).

Conclusions: In the future, it is necessary to investigate the pathogenic relationship between M-protein and autoantibodies in patients with neuropathies.

Background: This study aimed to investigate the effect and clinical implications of IL-1β on the development of aneurysmal subarachnoid hemorrhage.

Methods: This retrospective study included a total of 80 participants, and these participants were divided into the following two groups: control group (healthy participants) and experimental group (aneurysmal subarachnoid hemorrhage patients). Then, all of the participants received digital subtraction angiography or computed tomography angiography. Participants' general data were collected and analyzed. IL-1β expression in blood samples were determined by ELISA, and then IL-1β protein were determined by western blotting.

Results: A total of 80 participants was included in this study, and the participants` general data, including gender, age, and previous medical history, showed no significant differences between the experimental group and control group. The IL-1β value in the experimental group was significantly increased, and the difference was statistically significant (p < 0.05).

Conclusions: Upregulated IL-1β can promote the development of aneurysmal subarachnoid hemorrhage, indicating that IL-1β is a key factor in evaluating the prognosis of patients with aneurysmal subarachnoid hemorrhage.

Background: CRP is a hepatic acute-phase reactant protein, which is primarily induced by the interleukin-6 action due to an inflammatory/infectious process. Precision is closeness of agreement between indications or measured quantity values obtained by replicate measurements on the same or similar objects under specified conditions. Precision goals should be stated as the maximum allowable imprecision, SD, and/or CV expressed as a percentage (% CV) at each analyte´s concentration to be tested. The aim of this study was to verify the two different manufacturers' claims on C-reactive protein (CRP) based on the Clinical and Laboratory Standards Institute (CLSI) EP 15-A3 document.

Methods: To represent low, intermediate, and high level, 3 sera pools were prepared from remnant sera of patients. After the familiarization period of the operator, two runs per day (morning and afternoon) with ten replicates per run were performed for five days for each measurand concentrations. Original CRP kit of Beckman uses latex immunoturbidimetric assay (OSR 6299, Beckman) and novel kit practices enzymatic immunoturbidimetric assay (B21220, Bioanalytic) were utilized to measure CRP. For both kits, only one calibration was applied before the study in favor of daily internal control results within the eligible area.

Results: The original kit failed at all levels, even if the upper verification limit was applied. Novel kit passed for the intermediate- and high-level claim of the manufacturers. The highest CV% was 5.24%, and the EFLM recommendation for CRP is 8.5% at the optimum level.

Conclusions: Such experiments with expanded data should be performed with daily calibration to provide manufacturers' claim. Otherwise, it is hard to pass the precision verification. Studies are valuable in terms of demonstrating the reproducibility of the produced kits in end-user laboratories.