Scandinavian Journal of Clinical & Laboratory Investigation最新文献

Obesity alters lipid and carbohydrate metabolism, which has an impact on micronutrient status. Zinc affects lipid and glucose metabolism while also acting as an anti-inflammatory and antioxidant in various physiological processes. It has a direct effect on the insulin-signaling system and acts as an insulin mimic. In this study we predicted that zinc deficiency in obese Serbian adults affects anthropometric parameters, lipid and glucose metabolic profiles, inflammation, and atherosclerotic markers. We conducted a case-control study with 31 adult obese individuals and 31 controls. Different methods were used to determine the values of anthropometric and biochemical parameters. Obese participants had significantly decreased serum zinc levels compared to controls (p < .01). In obese subjects, there is a significant negative correlation between zinc and body weight (ρ = -0.324, p < .05), body mass index (ρ = -0.351, p < .05), body fat mass (%) (ρ = -0.431, p = .006), and triglycerides (ρ = -0.317, p < .05), as well as a positive correlation between zinc and high-density lipoproteins (ρ = +0.453, p < .01) and lipoprotein (a) (ρ = +0.417, p < .01). Atherosclerotic index and lipoprotein (a) were significantly related to zinc (p = .0022 and p = .0016, respectively) independently of each other in obese subjects. Our results suggest that the determination of zinc levels in obese persons and their correlation with anthropometric and metabolic parameters could help in the identification of individuals at higher risk for cardiovascular disease.

Hospitalized stroke patients are at high risk of developing circadian disruption due to lack of natural sunlight. This may affect the circadian rhythm of the calcium metabolism. This study is a secondary explorative analysis from a Randomized Controlled Trial. Acute stroke patients requiring a minimum of two weeks of rehabilitation were randomized to an Intervention unit (IU) equipped with naturalistic light or a Control unit (CU) with standard indoor lighting. Blood was drawn across 24 h at inclusion and discharge in 45 patients, 25 from the IU and 20 from the CU. Calcium showed significant rhythmicity at inclusion and discharge in both groups. Alkaline phosphatase, parathyroid hormone (PTH), and Vitamin D exhibited no significant rhythmicity at inclusion or discharge in either group while phosphate exhibited rhythmicity at discharge in the CU. PTH levels were elevated in the CU group compared to the IU group at time of discharge. Of the measured parameters, only calcium exhibited circadian rhythmicity after stroke. Naturalistic light did not have any influence on the rhythmicity, indicating that light may not be the main circadian regulator of the circadian oscillations that regulate calcium metabolism. PTH seems to be decreased by naturalistic light.

Background: Direct oral anticoagulants (DOACs) can interfere with coagulation analyses, causing erroneous results such as false-positive lupus anticoagulant and false-normal antithrombin, threatening patient safety when overlooked. A test using a prothrombin time quotient method to detect DOAC presence in plasma samples is now commercially available, the MRX PT DOAC, with the result expressed as Clot Time Ratio (CTR).

Objectives: Evaluate the ability of MRX PT DOAC to identify interfering apixaban or rivaroxaban concentrations, identify non-interfering or interfering patient samples, and detect whether a patient is on DOAC treatment.

Methods: An MRX PT DOAC reference interval was established, and MRX PT DOAC results related to FXa inhibitor concentrations. MRX PT DOAC patient plasma results were related to indications of analytical interference with lupus anticoagulant and antithrombin analyses and with the patients' anticoagulant drug use, according to medical records.

Results: The MRX PT DOAC CTR reference interval was 0.98-1.38. MRX PT DOAC apixaban and rivaroxaban interference detection sensitivity was 1.00 (0.96 - 1.0). For subgroups from 315 patient plasma samples, the negative predictive values estimates were 0.84 or above (95% confidence interval minimum 0.64) for excluding analysis interference with the lupus anticoagulant and antithrombin analyses and for excluding DOAC treatment as per medical records. All 9 interference-indicating DOAC samples were identified for the lupus anticoagulant analyses, 5 out of 11 for antithrombin.

Conclusions: The MRX PT DOAC is a potential screening tool for interference. Confirming results in a larger DOAC patient group and further investigating the antithrombin interference detection uncertainty is important.

Objectives: Quantification of cytokine is indispensable to elucidate the mechanism of immune regulation at the molecular level, thereby contributing to the diagnosis and treatment of several diseases. Here, we aimed to determine the effect of detection method and storage conditions of specimens on the quantification of cytokine levels.

Methods: We used four vacuum blood collection tubes containing EDTA, heparin, clot activator, gel and compared the changes in the expression levels of 14 cytokines in serum and plasma samples at different temperatures and durations of storage using AimPlex flow cytometry-based immunoassay. In addition, we analyzed the changes in cytokine sensitivity and its clinical relevance after re-establishing cutoff values compared to those set by the manufacturer.

Results: The cytokine levels were higher in the plasma of healthy individuals than in their serum. Reliable values for most cytokines were obtained in gel-serum samples, centrifuged within 4 h of collection, and stored at -20 °C for up to 24 h. We measured cytokine levels in 1064 healthy controls using tubes containing separation gel to recalculate their cutoff values and observed changes in cytokine positivity in patients. IL-6 positivity increased from approximately 90% to 95% in patients with sepsis and severe pneumonia. Similarly, IL-8 increased from 48.7% and 41.7% to 79.5% and 63.9% in patients with sepsis and severe pneumonia.

Conclusions: Cytokines are more stable in gel-serum than in plasma or clot activator-serum, and they should be quantified within 4 h or within 24 h if the sample is centrifuged and stored at -20 °C.

Hemolysis (H-index) and icteric indexes (I-index) are widely used in clinical laboratories to control interferences. Since I-index correlates with bilirubin, it can aid in deciding whether to analyze bilirubin levels. The study aims to evaluate I-index use for this purpose, considering H-index interference on I-index. This retrospective study included H-index, I-index and total bilirubin results, all analyzed using the Mindray BS800M. Total bilirubin was analyzed using the Vanadate oxidase method. Patients were categorized according to their H-index values in multiples of 0.5. Group-0 had the lowest hemolysis (<0.5 g/L), and Group-10 had the highest hemolysis (>5 g/L), with a total of 11 groups. ROC analysis determined optimal I-index cut-offs to differentiate normal and abnormal bilirubin levels, calculating PPV, NPV, specificity and sensitivity. Indexes of 55,306 patients and total bilirubin results of 26,781 patients were evaluated. There was no significant difference between the groups in pairwise comparison for bilirubin results but significant differences were observed in I-index values. When the I-index values were examined, there were significant differences between Group 0,1,2,3,4, and all groups from 0 to 10 (p < 0.001). As hemolysis increased, the I-index cutoff values decreased. While the cut-off values for Group-0 and Group-4 ranged from 16.70 to 14.15 μmol/L, in Group-5 (hemolysis 2.5-3 g/L), the cut-off was 6.50 μmol/L, in Group-6 and Group-7, it was -2.35 μmol/L. In Group-10, this value dropped to -42.55 μmol/L. Our findings suggest using the I-index to spot hyperbilirubinemia and save on testing. However, different cut-off values should be calculated according to the hemolysis value.

While thrombocytopenia's link to mortality is known, the prognostic impact of longitudinal trajectories of platelet indices in combination with analysis of thrombocytopenia's mediating role remains unexplored. This is the first study that addresses this significant gap by investigating the association between seven platelet indices trajectory subphenotypes and ICU mortality, considering thrombocytopenia's mediating influence.

Four hundred and twenty-one adult ICU patients were enrolled in this longitudinal cohort study. Three trajectories were identified for each platelet index, namely: descending, stable, and ascending, and using a regression, receiver-operating characteristic curve, and mediation analysis, their associations with 90-day mortality were evaluated with the mediating effect of thrombocytopenia. The findings were adjusted (prefixed 'a') for covariates.

The heterogeneous trajectories significantly associated with 90-day mortality included: descending platelet count (PC) [aOR, 2.75 (CI, 1.56-4.85), p = 0.0005, aAUC, 0.783], descending plateletcrit (PCT) [aOR, 3.49 (CI, 1.88-6.46), p = 0.0001, aAUC, 0.802], ascending platelet distribution width (PDW) [aOR, 2.04 (CI, 1.13-3.71), p = 0.0188, aAUC, 0.776], and ascending percent-immature platelet fraction (%-IPF) [aOR, 2.25 (CI, 1.29-3.94), p = 0.0045, aAUC, 0.778], with 11.6% (p = 0.027), 12.0% (p = 0.019), 22.1% (p = 0.011), and 15.9% (p = 0.024) effects mediated by thrombocytopenia, respectively. In contrast, ascending mean platelet volume (MPV) was significantly and independently associated with mortality [aOR, 3.04 (CI, 1.45-6.39), p = 0.0033, aAUC, 0.781], without the effect mediated by thrombocytopenia (p = 0.056). The trajectories of platelet-large cell ratio (P-LCR) and absolute-immature platelet count (A-IPF) were not significantly associated with the risk of mortality (p > 0.05).

This study demonstrated that descending PC and PCT and ascending PDW and %-IPF, mediated by thrombocytopenia, and ascending MPV, without mediation by thrombocytopenia, are useful longitudinal trajectories for predicting 90-day mortality in the ICU.

The objective of the current review was to identify whether clinically established lung function metrics of ventilatory and diffusion capacity obtained by standardised methodology are consistent with superior lung function in athletes, and whether this is related to maximal oxygen uptake (V̇O_2max). Three independent reviewers performed a literature search in PubMed, Scopus, and reference screening. Data was extracted and analysed according to a predefined strategy. Studies published between 1970 and 2023 on athletes reporting V̇O_₂max and at least one of the following lung function metrics: predicted forced expiratory volume in the first second of a forced vital capacity manoeuvre (FEV₁%pred); predicted forced vital capacity (FVC%pred); predicted total lung capacity (TLC%pred); predicted pulmonary diffusion capacity for carbon monoxide (D_L,CO%pred). Data on population size, age, sex, type of sports, as well as FEV₁%pred, FVC%pred, TLC%pred, D_L,CO%pred, and V̇O_2max were extracted. Standardised mean, differences, and 95% CI were calculated when data were sufficient. In total, 13 original studies encompassing 193 individuals across various sports disciplines met the inclusion criteria. Pooled FEV₁%pred was 111% (108-113%; 13 studies; n=193), FVC%pred 112% (108-116 %; 7 studies; n=118), TLC%pred 106% (103-108 %; 4 studies; n=60), and D_L,CO%pred 121% (120-122 %; 2 studies; n=23). None of the studies provided sufficient data to evaluate the relationship between any of the lung function metrics and V̇O_2max. In conclusion, athletes consistently exhibit high ventilatory and diffusing capacity metrics, but it is still unknown whether this is related to V̇O_2max.

Analytical errors related to endogenous or exogenous substances are a cause of unnecessary investigation, intervention, and patient concern especially in immunoassay platforms. In this report, we systematically screened for estradiol interference using a practical algorithm. For extended research in interference screening, repeated estradiol measurements for control and case samples were carried out for method comparison (three immunoassay platforms and one liquid chromatography-mass spectrometry (LC-MS/MS) measurement), dilution test, polyethylene glycol (PEG) precipitation, and heterophile antibody blocking tube. When serial dilutions were applied to the sample, a deviation from linearity was observed when compared to the control sample. With PEG precipitation, the recovery rate of 63%. While the patient's serum estradiol value was 389.02 pmol/L using the Siemens Atellica immunoassay method, the same sample was <36.7 pmol/L in the Abbott immunoassay method and 34.9 pmol/L in the Roche immunoassay platform. Applying the LC-MS/MS method, the patient had a serum estradiol of 3.33 pmol/L. Immunoassays are susceptible to interferences that can cause high estimates due to cross-reactivity. Therefore, LC-MS/MS may be more suitable than immunoassays for preventing misdiagnosis and inappropriate treatments, especially for children.

Hemoglobin Bart's hydrops fetalis is the most severe form of α-thalassemia, caused by homozygous α⁰-thalassemia, which is highly prevalent in Southeast Asian countries. Simple and rapid identification of α⁰-thalassemia carrier and prenatal diagnosis of Hemoglobin Bart's hydrops is essential in the region. We have developed a multiplex RPA assay for simple detection of α⁰-thalassemia (SEA and THAI deletions) and tested it in carrier detection (n = 125) and prenatal diagnosis of Hb Bart's hydrops fetalis syndrome (n = 30). The sensitivity, specificity, positive predictive value, and negative predictive value for detecting α⁰-thalassemia carriers were 100% for both SEA and THAI deletions. The assay correctly identified 42 carriers of α⁰-thalassemia (SEA deletion), 4 carriers of α⁰-thalassemia (THAI deletion), and 79 non-carriers. For prenatal diagnosis, the results of RPA revealed a 100% concordance (30/30) with the conventional gap-PCR analysis. The multiplex RPA assay is a rapid, reliable, and cost-effective method for diagnosing α⁰-thalassemia-related disorders in routine clinical settings. This assay has the potential to significantly contribute to the prevention and control of Hb Bart's hydrops fetalis in the region.