Laboratory medicine最新文献

Introduction: We sought to assess whether rapid antimicrobial susceptibility testing (AST) directly from positive blood culture bottles for Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa can be used in Chinese hospitals.

Methods: Rapid AST was performed on each positive blood culture bottle. Categorical rapid AST results at 8 to 10 and 16 to 18 hours were compared with those from the VITEK 2 system (bioMérieux). Minimum inhibitory concentrations and zone diameter were interpreted according to Clinical and Laboratory Standards Institute (CLSI) standard M100-S34, published in 2024.

Results: At 8 to 10 hours, the overall categorical agreement for E coli, K pneumoniae, and P aeruginosa was 99.1%, 98.4%, and 95.8%, respectively. At 16 to 18 hours, these rates were 97.4%, 98.9%, and 99.1%, respectively. For E coli, the categorical agreement ranged from 97.2% (ceftazidime at 8-10 hours) to 100% (ampicillin and meropenem at 8-10 and 16-18 hours and ciprofloxacin at 16-18 hours). The categorical agreement for K pneumoniae varied from 96.5%with ceftazidime at 8 to 10 hours to 100% with meropenem and ciprofloxacin at 16 to 18 hours. For P aeruginosa, the categorical agreement ranged from 93.7% (meropenem at 8-10 hours) to 100% (ciprofloxacin at 16-18 hours).

Discussion: The CLSI rapid AST method is reliable for E coli, K pneumoniae, and P aeruginosa in Chinese hospitals.

Introduction: Blue-green, refractile, and irregularly contoured inclusions found in the cytoplasm of some leukocytes are a rare and underdiagnosed finding. They have been a subject of discussion among professionals regarding their composition and clinical significance. These inclusions are strongly associated with ischemic liver injury in a multitude of clinical contexts.

Methods: Patients admitted between March 2021 and March 2022 were included in this study. Medical records, laboratory results, and progression were reviewed in all patients where the presence of these inclusions in peripheral blood smears observed under the optical microscope was reported.

Results: The etiologies of the various liver failures that triggered the appearance of these inclusions were highly varied. Alanine aminotransferase, aspartate aminotransferase, and lactate dehydrogenase levels were highest in these patients. Lactic acidosis was another consistent feature associated with the inclusions. The mortality rate was 84.6%.

Discussion: Peripheral blood smear is the only procedure that results in detection of these inclusions. Therefore, the clinical laboratory professional must be aware of the existence of these inclusions and consider notifying the responsible emergency physicians. In contrast, emergency physicians must also be aware of the severity of this finding and take it into account in the overall clinical assessment of critically ill patients.

Introduction: Cerebrospinal fluid (CSF) biomarkers for Alzheimer disease are US Food and Drug Administration approved and implemented on automated platforms, allowing for widespread use and higher throughput. Although low-bind polypropylene tubes for accurate quantification of amyloid-β (Aβ) have been well studied, less is known about the impact of other common preanalytical variables on quantification of biomarkers for Alzheimer disease. This study evaluated the effects of refrigerated transportation and hemolysis on the concentrations of Aβ42, phosphorylated tau 181, and total tau.

Methods: The Roche Diagnostics Elecsys β-Amyloid (1-42) CSF II, Elecsys Phospho-Tau (181P) CSF, and Elecsys Total-Tau CSF assays were used on the Roche cobas pro e 801 platform to measure protein concentrations in residual CSF samples. Paired-difference testing was performed to determine the effects of simulated transportation and hemolysis on each analyte.

Results: For all 3 analytes, less than 10% difference was observed between the concentrations measured on day 0 and after 14 days of transportation and refrigeration. In contrast, 2.26 g/L free hemoglobin resulted in more than 10% negative bias in Aβ42 measurement compared with the 0 g/L control but did not affect phosphorylated tau 181 or total tau concentrations.

Discussion: Refrigerated transportation did not affect the analysis of Aβ42, phosphorylated tau 181, or total tau, whereas hemolysis can negatively affect results of Aβ42.

Introduction: Since the 1960s, the term thyrogastric syndrome has defined the association of autoimmune gastritis with autoimmune thyroid disease (ATD). Graves disease, one of the most common autoimmune thyroid diseases, has been associated with autoimmune gastritis. The aim of this study was to evaluate the frequency of anti-parietal cell antibodies (APCAs) in a cohort of patients with Graves disease.

Methods: Eighty-three patients with Graves disease and 83 healthy adult blood donors were enrolled. All patients were positive for thyroid-stimulating hormone receptor antibodies (TRAbs). The APCAs were detected using an indirect immunofluorescence technique.

Results: The frequency of APCAs was significantly higher in the patients group than in the control group (12% vs 0% [95% UC, 5%-19%]; P = .001). The frequency of APCAs was slightly higher in female patients with Graves disease (12.7%) than in male patients (10%), but the difference was not statistically significant. The mean (SD) titer of TRAbs in APCA-positive patients was not statistically higher than in APCA-negative patients (21.4 [17] IU/L vs 16.8 [14.9] UI/L; P = .37). No correlation was found between titers of APCA and titers of TRAbs (r = -0.49, P = .148).

Discussion: Although APCAs are frequent in patients with Graves disease, their significance has to be determined.

Introduction: The prognosis of acute myeloid leukemia is stratified by genetic abnormalities; however, the detection sensitivity varies by method. The KIT D816 mutation is frequently found in core binding factor leukemia and is associated with a poor prognosis. In this study, we aimed to investigate the performance of multiplex droplet digital polymerase chain reaction (ddPCR) for detecting KIT D816 mutations and propose the practical mutation analysis method for clinical laboratory testing.

Methods: We evaluated the detection limit of ddPCR using mixed probes for HEX-labeled wild-type and FAM-labeled mutations (D816V, D816Y, and D816H) by analyzing plasmid mixtures containing these sequences. We compared the frequency of KIT mutations detected by direct sequencing and ddPCR in 20 patients with core binding factor leukemia.

Results: Multiplex ddPCR successfully discriminated between mutation types based on plot positions on a 2-dimensional map, with a detection limit of 0.1%. The frequency of D816 mutations was 42.5% using ddPCR and 20% using direct sequencing. Most patients with KIT D816 mutation require hematopoietic stem cell transplantation for chimeric gene clearance.

Discussion: Amplitude-based multiplex ddPCR efficiently provides sensitive and accurate genotyping of KIT D816 and has potential applications for other genetic abnormalities.

Introduction: Patients with hematologic malignancies who undergo immunosuppressive therapies such as chimeric antigen receptor T-cell (CAR-T) therapy are at high risk of prolonged SARS-CoV-2 infection due to impaired humoral immunity. Treatment options remain limited, with variable efficacy, in such settings.

Methods: We describe a 21-year-old man with Down syndrome and B-cell acute lymphoblastic leukemia complicated by B-cell aplasia following CD19-directed CAR-T therapy. The patient developed COVID-19 and experienced persistent symptomatic infection, with high viral load and prolonged reverse transcriptase-polymerase chain reaction (RT-PCR) positivity for more than 7 months.

Results: Despite multiple courses of remdesivir and extended weekly infusions of COVID-19 convalescent plasma (CCP), the patient remained viremic and intermittently symptomatic. Anti-SARS-CoV-2 immunoglobulin G titers were detectable only toward the latter time frame of treatment, and passive antibody therapy with CCP was insufficient for viral clearance. Ultimately, compassionate use of monoclonal antibody (mAb) therapy (casirivimab and imdevimab) was granted. Following administration, the patient achieved viral clearance for the first time, with resolution of symptoms and persistently negative RT-PCR findings for 8 months of available follow-up thereafter.

Discussion: This case illustrates the limitations of CCP in patients with prolonged SARS-CoV-2 infection and highlights the effectiveness of mAbs in achieving viral clearance in severely immunocompromised hosts. It supports targeted use of mAb therapy in select high-risk populations and reinforces the importance of specific passive immunotherapy strategies (when available) for the management of viremia in immunodeficient patients.

Introduction: For several years, concerns about perfluoroalkyl and polyfluoroalkyl substances (PFAS) have been growing, and clinical laboratories may have to perform a growing number of PFAS analyses. The use of serum tubes without a separator gel is currently recommended for the quantification of PFAS due to the concern that the compounds may adsorb to the gel. The impact of gel adsorption on the accuracy of the results, however, has not been evaluated.

Methods: Aliquots from a pool of blood spiked with PFAS were stored in gel-free clot activator tubes (CATs) and gel-containing BD SST II Advance tubes (serum separator tubes) for 2, 8, and 24 hours. The CATs and serum separator tubes were collected from 15 volunteers under typical sampling conditions. Concentrations of 16 PFAS were analyzed using liquid chromatography-tandem mass spectrometry, and the percentage of change in PFAS levels between both tube types was computed.

Results: Results showed minimal changes (<5%) for most PFAS within 24 hours, except for long-chain perfluorosulfonates (including perfluorooctane sulfonate), which seemed to exhibit adsorption of the gel. In samples from volunteers, the observed changes were statistically significant for perfluorooctane sulfonate (P <.001).

Discussion: Based on our analysis, we recommend using CATs to avoid PFAS underestimation.

Introduction: Colorectal cancer (CRC) is known to have an association with circular RNAs (circRNAs) and immune checkpoint factors. This study sought to examine the expression levels of hsa_circ_0000284 and hsa_circ_0004771 molecules and the programmed cell death 1 protein (PD-1) and ecto-5'-nucleotidase (CD73) immune checkpoints in the peripheral blood of patients with CRC as well as the ratios of circular to linear forms of homeodomain-interacting protein kinase 3 (HIPK3) and nuclear receptor interacting protein 1 (NRIP1).

Methods: Real-time polymerase chain reaction (PCR) and flow cytometry were used to assess quantitatively the expression level of circRNAs, CD73, and PD-1 in blood samples from patients with CRC and healthy control individuals. The expression of CD73 and PD-1 molecules was analyzed using FlowJo software, and the expression levels of circRNAs, CD73, and PD-1 were calculated with real-time PCR analysis.

Results: Real-time PCR analysis revealed a statistically significant increase in the linear form of hsa_circ_0004771 (linNRIP1) and PD-1 gene expression in patients' blood compared with control individuals. In addition, the circHIPK3:linHIPK3 and circNRIP1:linNRIP1 ratios are statistically significantly higher in patients than in healthy control individuals. The flow cytometry assessment indicated a statistically significant increase in PD-1 on the surface of lymphocytes and monocytes and an increase in CD73 on the granulocytes of patients compared with the healthy control individual.

Discussion: Based on these findings, hsa_circ_0000284, hsa_circ_0004771, PD-1, and CD73 were statistically significantly increased in our cancer group. If further research were done, these blood markers could potential be biomarkers for CRC progression.

Introduction: This study investigated the association between thyroid disorders and breast cancer.

Methods: A retrospective case-control study was conducted using electronic health record data from an academic health care system. This study included 300 female patients 18 years of age and older with a diagnosis of breast cancer and 300 control individuals with no cancer history. Statistical analysis included calculation of prevalence and odds ratios for association, ꭓ2 for categorical variables, and mean (SD) and median for age.

Results: Patients with breast cancer were, on average, 58 years old, statistically significantly older than patients without cancer (P < .001). Patients were 6 times more likely to have thyroid disorders (P < .001), including hypothyroidism (P < .001), than women who did not have cancer. Patients with triple-negative breast cancer had 4 times higher odds of being diagnosed with thyroid disorders overall (P < .001) and hypothyroidism (P < .001) compared with control individuals. Moreover, patients with estrogen receptor-positive/progesterone receptor-positive breast cancer were 15 times more likely to develop the autoimmune disorder Hashimoto thyroiditis compared with controls, which was statistically significant (P = .026).

Discussion: This study highlighted a strong association between breast cancer and thyroid disorders, particularly indicating a higher prevalence of hypothyroidism among individuals with breast cancer.

Introduction: The coexistence of primary thyroid lymphoma (PTL) and papillary thyroid carcinoma (PTC) is extremely rare, especially in young populations. Therefore, it is extremely important to understand and master the clinical manifestations, diagnosis, treatment, and prognosis of these diseases.

Methods: This article reports a case of a 29-year-old female patient with recurrent right neck swelling and pain with fever and progressive enlargement of the thyroid gland.

Results: The imaging examination results showed goiteromegaly and a mass. Subsequent surgical resection was performed, and postoperative pathology confirmed the coexistence of PTC and PTL. The patient then received 8 cycles of chemotherapy plus targeted therapy. During follow-up, the tumor disappeared, and the disease was in complete remission.

Discussion: It is extremely rare for a young patient with recurrent neck pain and fever to have PTC and PTL simultaneously. We report this case to provide a basis for the diagnosis and treatment of the coexistence of PTC and PTL to improve clinicians' understanding of these coexisting diseases in young people to avoid misdiagnosis and missed diagnosis.