Our study aimed to compare the accuracy of serum biomarkers for the diagnosis of macrophage activation syndrome (MAS) complicating systemic juvenile idiopathic arthritis (s-JIA). Serum cytokine levels (neopterin, IL-18, and CXCL9 and soluble tumor necrosis factor receptor type I (sTNFR-I) and II) were determined by enzyme-linked immunosorbent assay in 78 patients with s-JIA, including 21 with MAS. Receiver operating characteristic curve analysis revealed area under the curve values and cut off values of neopterin, IL-18, CXCL9, sTNFR-II/I ratio and ferritin were 0.9465/19.5 nmol/l, 0.8895/69250 ng/ml, 0.9333/3130 pg/ml, 0.9395/3.796 and 0.8671/2560 ng/ml, respectively. Serum neopterin levels were significantly elevated in patients with MAS and those were correlated positively with disease activity. In conclusion, serum neopterin levels may be used as a promising indicator of disease activity in s-JIA and MAS and for evaluating it. It may also be a useful marker to diagnose the transition to MAS from active-phase s-JIA.

中文翻译：

---

血清生物标志物用于诊断巨噬细胞活化综合征并发系统性幼年特发性关节炎的比较。

我们的研究旨在比较血清生物标志物诊断巨噬细胞活化综合征（MAS）并发系统性幼年特发性关节炎（s-JIA）的准确性。通过酶联免疫吸附法测定了78例s-JIA患者（包括21例MAS患者）的血清细胞因子水平（新蝶呤，IL-18和CXCL9以及I型可溶性肿瘤坏死因子受体（sTNFR-I）和II）。接收者工作特征曲线分析显示新蝶呤，IL-18，CXCL9，sTNFR-II / I比和铁蛋白的曲线值和截断值下的面积分别为0.9465 / 19.5 nmol / l，0.8895 / 69250 ng / ml，0.9333 / 3130 pg / ml，0.9395 / 3.796和0.8671 / 2560 ng / ml。MAS患者的血清新蝶呤水平显着升高，且与疾病活动呈正相关。综上所述，血清新蝶呤水平可以用作s-JIA和MAS疾病活动的有前途的指标，并可以对其进行评估。它对于诊断从活动期s-JIA到MAS的转变也可能是有用的标记。