We investigated serum levels of 29 cytokines and immune-activated kynurenine and tetrahydrobiopterin pathway metabolites in 15 complex regional pain syndrome (CRPS) subjects and 14 healthy controls. Significant reductions in interleukin-37 and tryptophan were found in CRPS subjects, along with positive correlations between kynurenine/tryptophan ratio and TNF-α levels with kinesiophobia, tetrahydrobiopterin levels with McGill pain score, sRAGE, and xanthurenic acid and neopterin levels with depression, anxiety and stress scores. Using machine learning, we identified a set of binary variables, including IL-37 and GM-CSF, capable of distinguishing controls from established CRPS subjects. These results suggest possible involvement of various inflammatory markers in CRPS pathogenesis.

中文翻译：

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复杂区域疼痛综合征的新型免疫生物标志物

我们调查了 15 名复杂区域疼痛综合征 (CRPS) 受试者和 14 名健康对照者的 29 种细胞因子和免疫激活的犬尿氨酸和四氢生物蝶呤通路代谢物的血清水平。在 CRPS 受试者中发现白细胞介素 37 和色氨酸显着减少，同时犬尿氨酸/色氨酸比率和 TNF-α 水平与运动恐惧症、四氢生物蝶呤水平与 McGill 疼痛评分、sRAGE 和黄尿酸和新蝶呤水平与抑郁、焦虑症呈正相关和压力分数。使用机器学习，我们确定了一组二元变量，包括 IL-37 和 GM-CSF，能够区分对照与已建立的 CRPS 受试者。这些结果表明各种炎症标志物可能参与 CRPS 发病机制。