Laboratory medicine最新文献

Background: Single-platform flow cytometry technology together with CD45-gating is becoming the method of choice for absolute CD4 T cell enumeration. Immunological assessment of HIV patients by monitoring CD4 can provide valuable information on antiviral treatment response and disease progression.

Methods: A total of 97 HIV-positive individuals were recruited from 2 hospitals in Tripoli, Libya, and 14 healthy blood donors. The HIV-infected individuals were classified by CD4+ count into HIV-positive (>200 cells/µL) or AIDS (≤200 cells/µL) groups. CD4+ and CD8+ cell counts were determined and compared among the groups and with similar published data.

Results: The mean ± SD CD4+ cell counts were 1106 ± 442.8 cells/µL in healthy individuals, 460 ± 219.7 cells/µL in the HIV-positive group, and 78 ± 64.3 cells/µL in the AIDS group. The mean ± SD CD4+/CD8+ ratio was 1.6 ± 0.58, 0.4 ± 0.22, and 0.1 ± 0.1, respectively. CD4+ counts in Libyan healthy adults might be higher than those reported in several studies in other regions, whereas CD4+ counts in Libyan AIDS patients seem lower.

Conclusion: Reference values for T lymphocyte counts in Libyan healthy individuals should be investigated more extensively, and the reasons why Libyan AIDS patients seem to have such lower CD4+ counts should be examined.

Objective: In evaluation of systemic lupus erythematosus (SLE), anti-double-stranded DNA antibodies (anti-dsDNA) play a significant role in diagnosis, monitoring SLE activity, and assessing prognosis. However, evaluations of the performance and limitations for recently developed methods for anti-dsDNA assessment are sparse.

Methods: Specimens used for antinuclear antibody testing (n = 129) were evaluated for anti-dsDNA assay comparability across 4 medical centers in the United States. The methods compared were Werfen Quanta Lite dsDNA, Zeus Scientific dsDNA Enzyme Immunoassay, Bio-Rad multiplex immunoassay (MIA) dsDNA, ImmunoConcepts Crithidia, and Bio-Rad Laboratories Crithidia.

Results: For quantitative anti-dsDNA measurements, Spearman's correlation coefficient was highest between Zeus and Werfen (ρ = 0.86; CI, 0.81-0.90; P < .0001). Comparison of MIA to Werfen or Zeus yielded similar results to each other (ρ = 0.58; CI, 0.44-0.68; P < .0001; and ρ = 0.59; CI, 0.46-0.69; P < .0001, respectively), but lower than the correlation between Zeus and Werfen. Positive concordance between assays ranged from 31.4% to 97.1%, and negative concordance between assays ranged from 58.5% to 100%. The detection of anti-dsDNA in those with SLE diagnosis ranged from 50.9% to 77.4% for quantitative assays and 15.1% to 24.5% for Crithidia assays.

Conclusion: Current quantitative anti-dsDNA assays are not interchangeable for patient follow-up. Crithidia-based assays demonstrate high negative concordance and lack positive concordance among the methods.

Background: Test consolidation and total laboratory automation (TLA) were implemented in a core laboratory with a high volume of specimens in a medical center in Taiwan to reduce the costs of laboratory services and improve laboratory workflow and performance.

Methods: Using a retrospective research approach, 5 stat and 7 routine tests were used to analyze the in-laboratory to report turnaround time (IR-TAT). Mean, SD, medium, 90th percentile, outlier percentage of IR-TAT, full-time equivalents, productivity, tube touch moment (TTM), and financial impact were determined and compared pre- and post-TLA.

Results: The mean IR-TAT of overall stat chemical tests for inpatient and outpatient were 32.8% and 11.9% reductions, respectively. The productivity of each medical technologist increased by 32.4% per month, and there was a reduction of 5 medical technologists compared with the number required to complete the same tests before consolidation. The TTM of staff per year post-TLA decreased by 74.1% tube touches.

Conclusion: The efficiency of laboratory services was improved by consolidation to the core laboratory along with TLA implementation coupled with logic rules such as delta-check and autoverification. Effectiveness was improved as measured by an increase in productivity, labor reduction, staff safety, and cost reduction.

Background: Type 2 diabetes mellitus (T2DM) intricately involves disrupted lipid metabolism. Exosomes emerge as carriers of biomarkers for early diagnosis and monitoring. This study aims to identify lipid metabolites in serum exosomes for T2DM diagnosis.

Methods: Serum samples were collected from newly diagnosed T2DM patients and age and body mass index-matched healthy controls. Exosomes were isolated using exosome isolation reagent, and untargeted/targeted liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to identify and validate altered lipid metabolites. Receiver operating characteristic curve analysis was used to evaluate the diagnostic value of candidate lipid metabolites.

Results: Serum exosomes were successfully isolated from both groups, with untargeted LC-MS/MS revealing distinct lipid metabolite alterations. Notably, phosphatidylethanolamine (PE) (22:2(13Z,16Z)/14:0) showed stable elevation in T2DM-serum exosomes. Targeted LC-MS/MS confirmed significant increase of PE (22:2(13Z,16Z)/14:0) in T2DM exosomes but not in serum. PE (22:2(13Z,16Z)/14:0) levels not only positively correlated with hemoglobin A1C levels and blood glucose levels, but also effectively distinguished T2DM patients from healthy individuals (area under the curve = 0.9141).

Conclusion: Our research sheds light on the importance of serum exosome lipid metabolites in diagnosing T2DM, providing valuable insights into the complex lipid metabolism of diabetes.

Objective: This study aimed to investigate the diagnostic value of stress-induced phosphoprotein 1 (STIP1) in serum for hepatocellular carcinoma (HCC) and alpha-fetoprotein (AFP)-negative HCC (ANHC).

Methods: In this study, serum samples were collected from 158 HCC patients and 63 non-HCC patients. Logistic regression analysis was performed to identify independent risk factors associated with HCC and ANHC. The diagnostic values of each index for HCC and ANHC were analyzed using receiver operating characteristic (ROC) curve analysis.

Results: The STIP1, des-γ-carboxy prothrombin (DCP), and AFP levels were higher in the HCC groups than in the non-HCC groups (P < .05). Age, DCP, STIP1, and hepatitis B virus infection were independent predictors of HCC (P < .05). The diagnostic value of STIP1 for HCC was higher than that of DCP. Additionally, age, STIP1, and hepatitis B virus infection were independent predictors for ANHC patients. The ROC curve exhibited an area under the curve value of 0.919 for STIP1, with a diagnostic cutoff value of 68.5 U/mL. Moreover, 36 ANHC patients and 19 AFP-negative non-HCC patients were included to validate the diagnostic model. A total of 20 patients had STIP1 levels greater than 68.5 U/mL, resulting in diagnostic accuracy of 67.3%, sensitivity of 55.6%, and specificity of 89.5%.

Conclusion: STIP1 demonstrates excellent diagnostic value for HCC and ANHC.

Background: Glycated hemoglobin, or hemoglobin A1c (HbA1c), serves as a crucial marker for diagnosing diabetes and monitoring its progression. We aimed to assess the interference posed by common Hb variants on popular HbA1c measurement systems.

Methods: A total of 63 variant and nonvariant samples with target values assigned by the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC)-calibrated methods were included. We assessed 6 methods for measuring HbA1c in the presence of HbS, HbC, HbD, HbE, and fetal hemoglobin (HbF): 2 cation-exchange high-performance liquid chromatography (HPLC) methods (Bio-Rad D-100 and HLC-723 G8), a capillary electrophoresis (CE) method (Sebia Capillarys 3 TERA), an immunoassay (Roche c501), an enzyme assay system (Mindray BS-600M), and a boronate affinity method (Primus Premier Hb9210).

Results: The HbA1c results for nonvariant samples from the 6 methods were in good agreement with the IFCC-calibrated method results. The Bio-Rad D-100, Capillarys 3, Mindray BS-600M, Premier Hb9210, and Roche c501 showed no interference from HbS, HbC, HbD, and HbE. Clinically significant interference was observed for the HLC-723 G8 standard mode. Elevated HbF levels caused significant negative biases for all 6 methods, which increased with increasing HbF concentration.

Conclusion: Elevated levels of HbF can severely affect HbA1c measurements by borate affinity, immunoassays, and enzyme assays.

Background: Appropriate age- and sex-specific reference intervals for alkaline phosphatase (ALP) are essential to identify patients with hypophosphatasia (low ALP) and to avoid unnecessary ALP isoenzymes analysis (elevated ALP). This study used patient ALP historical data to statistically derive sex- and age-specific reference intervals.

Methods: The ALP values reported as part of clinical management during an 18 month period (from July 2021 to March 2023) were obtained. Following logarithmic transformation of ALP data and repeated removal of outliers, cumulative frequency plots were generated using a modified Hoffmann approach to derive age- and sex-specific reference intervals.

Results: Age-specific ALP reference intervals ranged from 110 to 250 and 120 to 295 U/L for males and females <15 days old, 80 to 400 and 90 to 380 U/L for males and females 15 days to 1 year old, 105 to 280 and 90 to 290 U/L for males and females 1 to 10 years old, 75 to 300 and 90 to 300 U/L for males and females 10 to 13 years old, 80 to 300 and 60 to 175 U/L for males and females 13 to 15 years old, 55 to 150 and 60 to 180 U/L for males and females 15 to 18 years old, and 55 to 140 and 60 to 147 U/L for male and female adults, respectively (>18 years old).

Conclusion: By applying derived ranges, a retrospective review of ALP isoenzymes would eliminate 24.5% of requests. Additionally, 9 neonates would have required investigation for possible hypophosphatasia.

We report a fatal case of Legionella feeleii endocarditis in a post-lung transplant patient. The diagnosis was delayed, as routine microbiological testing of nonrespiratory specimens does not account for extrapulmonary Legionella, and urine antigen testing only reliably detects Legionella pneumophila serogroup 1. This case also illustrates the utility of molecular sequencing for blood culture-negative endocarditis.

A 78-year-old male was seen in the emergency department (ED) with chest pain. Fifteen months earlier, he had presented to the ED with shoulder and elbow pain. High-sensitivity cardiac troponin I (hs-cTnI) testing was conducted at that time, which produced normal results of 10 and 13 ng/L (cutoff <48 ng/L). During the current admission, his electrocardiogram was unremarkable, with a borderline prolonged PR interval noted. The patient's hs-cTnI results were 25, 47, and 254 ng/L at 0, 1, and 7 hours, respectively. He was diagnosed with demand ischemia and admitted to the hospital. The detection of acute myocardial infarction in this case was made during the first sample collection (t = 0), despite the fact that this result was well within the normal range.

Objective: The ratio of γ-glutamyl transferase to HDL-C (GGT/HDL-C) has been proposed as a discriminator of metabolic syndrome. The purpose of this study was to elucidate the relationship between GGT/HDL-C and glycemic status in women.

Methods: The subjects were 18,218 middle-aged women who had received annual health checkups in their workplaces. They were divided by habitual alcohol intake into nondrinkers, occasional drinkers, regular light drinkers, and regular heavy drinkers.

Results: In overall subjects, hemoglobin A1c level and prevalence of diabetes tended to be higher in subjects with higher GGT/HDL-C, and GGT/HDL-C tended to be higher with an increase of alcohol intake. The odds ratio for hyperglycemia in subjects with vs. subjects without high GGT/HDL-C tended to be lower with an increase of alcohol intake, and the association between high GGT/HDL-C and hyperglycemia was significantly weaker in regular heavy drinkers than in nondrinkers.

Conclusion: In middle-aged women, there were positive associations of GGT/HDL-C with alcohol intake and glycemic status, and the association between GGT/HDL-C and glycemic status tended to be weaker with an increase of alcohol intake. Thus, alcohol use should be taken into account when GGT/HDL-C is used as a discriminator of diabetes.