Chopra Parul, Datta Sudip Kumar
Department of Hematology and Immunology, Dr. Lal PathLabs, New Delhi, India.
Department of Laboratory Medicine, All India Institute of Medical Sciences, New Delhi, India.
J Lab Physicians. 2020 Aug;12(2):84-91. doi: 10.1055/s-0040-1713690. Epub 2020 Jun 11.
We aim to report the simultaneous effect of different protein and lipid concentrations on sodium (Na ) and potassium (K ) measurement by direct and indirect ion selective electrodes (dISE and iISE) in patient samples. Na and K were measured in 195 serum samples received in the laboratory using iISE by Roche Modular P800 autoanalyzer and using dISE by XI-921 ver. 6.0 Caretium electrolyte analyzer. Serum total protein (TP), cholesterol (Chol), and triglycerides (TG) were measured using conventional photometric methods on Roche Modular P800 autoanalyzer. Differences for each pair of results for Na (Diff_Na = [Na Na ]) and K (Diff_K = [K K ]) were calculated. Patient subgroups with high, normal, or low TP (< 5, 5-7.9, or ≥ 8 g/dL), Chol (< 150, 150-299, or ≥300 mg/dL), or TG (< 150, 150-299, or ≥300 mg/dL) were compared using analysis of variance. Note that 95% confidence interval of Diff_Na and Diff_K were calculated to see the number of samples showing clinically significant differences. Diff_Na ( = 0.007) and Diff_K ( = 0.002) were found significant between samples with normal and high TP. However, effect of TG was not significant. Chol concentration affected Diff_Na significantly between low versus normal ( = 0.002), and high versus normal ( = 0.031) Chol groups. Diff_K was significant ( = 0.009) between low versus normal Chol. Clinically relevant disagreement of ≥|5| mmol/L for Na was observed in high percentage of samples including all subcategories; however, for K only 3.6% of the total samples showed disagreement of ≥ |0.5| mmol/L. A multivariate regression equation based on fit regression model was also derived. Summarily, interchangeable use of electrolyte results from dISE and iISE is not advisable, especially in a setting of hyperproteinemia (≥8 g/dL) or hypercholesterolemia (≥300 mg/dL); more so for Na .
我们旨在报告不同蛋白质和脂质浓度对患者样本中钠（Na⁺）和钾（K⁺）通过直接和间接离子选择电极（dISE和iISE）测量的同时影响。使用罗氏Modular P800自动分析仪的iISE和Caretium电解质分析仪XI - 921版本6.0的dISE对实验室收到的195份血清样本中的Na⁺和K⁺进行测量。使用罗氏Modular P800自动分析仪上的传统光度法测量血清总蛋白（TP）、胆固醇（Chol）和甘油三酯（TG）。计算每对Na⁺（Diff_Na⁺ = [Na⁺dISE - Na⁺iISE]）和K⁺（Diff_K⁺ = [K⁺dISE - K⁺iISE]）结果的差异。使用方差分析比较TP（<5、5 - 7.9或≥8 g/dL）、Chol（<150、150 - 299或≥300 mg/dL）或TG（<150、150 - 299或≥300 mg/dL）高、正常或低的患者亚组。计算Diff_Na⁺和Diff_K⁺的95%置信区间，以查看显示临床显著差异的样本数量。在正常和高TP的样本之间发现Diff_Na⁺（P = 0.007）和Diff_K⁺（P = 0.002）有显著差异。然而，TG的影响不显著。Chol浓度在低与正常（P = 0.002）以及高与正常（P = 0.031）Chol组之间对Diff_Na⁺有显著影响。Diff_K⁺在低与正常Chol之间有显著差异（P = 0.009）。在包括所有子类别的高比例样本中观察到Na⁺的临床相关差异≥|5| mmol/L；然而，对于K⁺，仅3.6%的总样本显示差异≥|0.5| mmol/L。还推导了基于拟合回归模型的多元回归方程。总之，不建议互换使用dISE和iISE的电解质结果，特别是在高蛋白血症（≥8 g/dL）或高胆固醇血症（≥300 mg/dL）的情况下；对于Na⁺更是如此。
