Clinical Chemistry Department, Hospital Álvaro Cunqueiro, EOXI Vigo, Spain.
CINBIO, Universidade de Vigo, Vigo, Spain.
PLoS One. 2021 Jun 10;16(6):e0252714. doi: 10.1371/journal.pone.0252714. eCollection 2021.
In previous studies, measuring the levels of calprotectin in patients with pleural effusion (PE) was an exceptionally accurate way to predict malignancy. Here, we evaluated a rapid method for the measurement of calprotectin levels as a useful parameter in the diagnosis of malignant pleural effusion (MPE) in order to minimise invasive diagnostic tests. Calprotectin levels were measured with Quantum Blue® sCAL (QB®sCAL) and compared with the gold standard reference ELISA method. Calprotectin levels in patients with benign pleural effusion (BPE) were significantly higher (p < 0.0001) than for MPE patients. We measured the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and positive and negative likelihood ratios (LRs) for a cut-off value of ≤ 14,150 ng/mL; the diagnostic accuracy was 64%. The odds ratio for PE calprotectin levels was 10.938 (95% CI [4.133 - 28.947]). The diagnostic performance of calprotectin concentration was better for predicting MPE compared to other individual parameters. Comparison of two assays showed a slope of 1.084, an intercept of 329.7, and a Pearson correlation coefficient of 0.798. The Bland-Altman test showed a positive bias for the QB®sCAL method compared to ELISA fCAL®. Clinical concordance between both these methods was 88.5% with a Cohen kappa index of 0.76 (95% CI [0.68 - 0.84]). We concluded that QB®sCAL is a fast, reliable, and non-invasive diagnostic tool for diagnosing MPE and represents an alternative to ELISA that could be implemented in medical emergencies.
在之前的研究中，测量胸腔积液（PE）患者的钙卫蛋白水平是预测恶性肿瘤的一种非常准确的方法。在这里，我们评估了一种快速测量钙卫蛋白水平的方法，作为诊断恶性胸腔积液（MPE）的有用参数，以尽量减少侵入性诊断测试。使用 Quantum Blue® sCAL（QB®sCAL）测量钙卫蛋白水平，并与金标准参考 ELISA 方法进行比较。良性胸腔积液（BPE）患者的钙卫蛋白水平明显高于（p < 0.0001）MPE 患者。我们测量了截断值≤14,150ng/mL 时的灵敏度、特异性、阳性预测值（PPV）、阴性预测值（NPV）、阳性和阴性似然比（LR）；诊断准确性为 64%。PE 钙卫蛋白水平的比值比为 10.938（95%CI[4.133-28.947]）。与其他单个参数相比，钙卫蛋白浓度对预测 MPE 的诊断性能更好。两种检测方法的比较显示斜率为 1.084，截距为 329.7，Pearson 相关系数为 0.798。Bland-Altman 检验显示 QB®sCAL 方法与 ELISA fCAL®相比存在正偏倚。这两种方法的临床一致性为 88.5%，Cohen kappa 指数为 0.76（95%CI[0.68-0.84]）。我们得出结论，QB®sCAL 是一种快速、可靠、非侵入性的诊断工具，可用于诊断 MPE，是 ELISA 的替代方法，可在医疗紧急情况下实施。
