Facultad de Medicina, Departamento de Pediatría, Universidad de Antioquia, Medellín, Colombia; Departamento de Pediatría, Hospital Pablo Tobón Uribe, Medellín, Colombia.
Unidad de Investigación Genética Molecular, UNIGEM-Colombia, Medellín, Colombia.
Biomedica. 2021 Dec 15;41(4):787-802. doi: 10.7705/biomedica.5849.
Introduction: There are no sensitive or specific tests available to diagnose systemic juvenile idiopathic arthritis (sJIA). Objective: To assess the utility as diagnostic tests of total ferritin (TF) levels greater than 5 times the normal value (TF>5N) and the decreased percentage (less than or equal to 20% of TF) of glycosylated ferritin (GF≤20%) for the diagnosis of sJIA in patients with fever of unknown origin evaluated by pediatric rheumatology. Materials and methods: We conducted an observational, cross-sectional study of diagnostic tests in children under 16 years of age hospitalized between 2010 and 2014. The reference diagnostic standard was the fulfillment of the classification criteria or confirmed diagnosis at follow-up. We determined the measures of utility of the tests. Results: We included 40 patients with fever of unknown origin, 11 with sJIA, and 29 with other diagnoses. The median TF was higher in sAIJ (3992 ng/ml) versus other causes of fever of unknown origin (155 ng/ml) (p=0.0027), as well as TF>5N (90.91% versus 51.72%) (p=0.023). The percentage of GF≤20% was higher in patients with other causes of fever of unknown origin (96.5%) compared to sJIA (81.8%) (p=0.178). TF>5N had a sensitivity of 91%, specificity of 48%, positive likelihood ratio (LR) of 1.76, and negative LR of 0.19 demonstrating greater utility for the diagnosis of sJIA than the combination of FT> 5N with GFR <20%, with a sensitivity of 81.8%, specificity of 48.3%, positive LR of 1.58, and negative LR of 0.38. Conclusion: In patients with FUO evaluated by pediatric rheumatology, TF> 5N proved useful as a screening test for the diagnosis of sJIA.
目前尚无敏感或特异性检查可用于诊断系统性幼年特发性关节炎（sJIA）。目的：评估总铁蛋白（TF）水平大于正常值 5 倍（TF＞5N）和糖化铁蛋白（GF≤20%）减少百分比（小于或等于 TF 的 20%）作为儿科风湿病评估的不明原因发热患者 sJIA 诊断测试的效用。材料与方法：我们进行了一项观察性、横断面研究，对 2010 年至 2014 年住院的 16 岁以下儿童进行诊断性检测。参考诊断标准是满足分类标准或随访时的确诊诊断。我们确定了这些检测的有效性衡量标准。结果：我们纳入了 40 名不明原因发热患者，其中 11 名为 sJIA，29 名为其他诊断。sJIA 的铁蛋白中位数（3992ng/ml）高于其他不明原因发热的原因（155ng/ml）（p=0.0027），以及铁蛋白＞5N（90.91%对 51.72%）（p=0.023）。GF≤20%的百分比在其他不明原因发热患者中较高（96.5%），与 sJIA（81.8%）相比（p=0.178）。TF＞5N 的敏感度为 91%，特异性为 48%，阳性似然比（LR）为 1.76，阴性似然比（LR）为 0.19，表明其在 sJIA 诊断中的效用大于 TF＞5N 与 GF＜20%的组合，其敏感度为 81.8%，特异性为 48.3%，阳性 LR 为 1.58，阴性 LR 为 0.38。结论：在儿科风湿病评估的不明原因发热患者中，TF＞5N 可作为 sJIA 诊断的筛查试验。
